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Dakin Solution

DAKIN SOLUTION. Solution is harmless when injected subcutaneously but dangerous intravenously, as it is It should never be injected under pressure into deep wounds for fear of absorption. It is only slightly toxic and does not set up any marked irritation in wounds. On tissues deprived of circulation it brings about their dissolution, and the surface of the living tissues rapidly clears up. Clots and gan practice. It is non-toxic, does not irritate, and promotes reparation. The solution is made by adding 5 to 7 grains to 1 pint of sterile water at 122° F. and left to stand for two hours. It should not be filtered.

Drainage.

One of the principles instituted for the successful treatment of aseptic and infected wounds is the removal of secretions. This is to a great extent not required in operation wounds where strong and irritating solutions of anti septics are avoided, hwmorrhage is arrested, all blood-clots removed,"dead spaces"or pockets for the collection of serum and blood obliterated, strict asepsis carried out, and firm pressure maintained.

Drainage is obtained by making a fairly wide dependent orifice or by inserting a drain into the depth of the wound with an outside or low level outlet. It is indicated in accidental wounds, in the open method of castration, in those operation wounds forming large and deep cavities, as in cystic elbow and knee, shoulder abscess, poll-evil, fistulous withers, in those suppurations with burrowing into intermuscular spaces, especially those in the anterior femoral region, in large hematomata, purulent collec tions, and in pleural, pericardial, and peritoneal effusions.

A drain should always be used where blood clots exist and are not removed, serum is secreted, and infection present. Serum, blood-clots, and purulent collections, if pent up in a wound, form good culture media for putrefactive bacteria, and if absorbed into the system they set up malaise when they do not produce general infection or serious intoxication.

A dependent orifice can be obtained by making a wide incision or opening into the lowest part of the outer wall of a pocket of tissue in deep horizontal or vertical wounds or in circum scribed suppurations. In the case of a vertical or oblique wound in which there may not be any pocketing or hollow spaces, leaving out one or two of the sutures at the lower end of the wound suffices to afford drainage.

In those instances in which mechanical means may be deemed advisable in the drainage of wounds, abscesses, cysts, and sinuous cavities, it is not necessary to make a large opening but only one sufficient for the passage of the drain. The opening or perforation may be made with a pointed bistoury, sharp-pointed seton needle, or trocar and cannula.

Many materials have been introduced for mechanical drainage purposes, such as tow, lint, gauze, ribbon or tape (impregnated with anti septics or germicides), silk, catgut, silkworm gut, horse-hair, kangaroo tendon, and perforated glass, vulcanite, rubber or metal tubing. They are usually maintained in position by their own pressure in the wound, by a bandage or other dressing, or by a suture, drainage-tube pin, or safety-pin passed through the material and the lip of the wound.

The commonest drainage material used in veterinary practice is coarse linen or fibre tape passed in the manner of a seton and knotted in the form of a bow at both ends to prevent it slipping out of position. Instead of a bow - knot, each end may be passed through a perforated disc of leather and then knotted. Sometimes both ends are tied together so as to form a loop and not get displaced by the movements of the animal.

Packing a cavity with a strip of gauze or a pledget of tow is another very common method adopted in veterinary practice. It is very useful where drainage cannot be effected by a dependent orifice. The use of tow is objection able because after the pledget is removed fibres of the material are liable to remain, acting like a foreign body in the wound, and unless removed prevent reunion.

A very useful drain is made of a strip of gauze rolled into the shape of a cigarette, the middle part of the roll being encased in thin rubber tissue, leaving both extremities for an inch or more uncovered by the rubber (cigarette drain). Other modifications of this drain are made of strands of silk, short narrow strips of gauze, or short lengths of cotton-wick. Such drains, before being introduced into wounds, should be moistened with an antiseptic solution in order to facilitate capillarity.

In case of an operation wound showing signs of infection, as redness or a purplish tint and puffiness, which is most marked at the site of the sutures, rather than remove the whole of the sutures and allow the wound to gape it is better to remove the sutures at either end of the wound and establish drainage by drawing through the wound under the remaining sutures a strip of iodoformized gauze threaded on a probe or seized by thin sinus forceps passed through the wound.

Drains may also be made of several strands of horse-hair, silkworm - gut, catgut, or silk doubled so as to form a loop at one end. The free ends may be kept together by plaiting or by interweaving a fine piece of silk commencing from the neck of the loop and working down ward to the free ends. The loop end is placed in the depth or the distal end of the wound and the free ends hang out of it.

Capillary drainage is effected by a few long horse-hairs passed vertically through the whole depth of a cyst or abscess by means of a long needle or eyed-probe, each end of the drain being knotted to keep it in position.

Rubber tubing of various calibres is prepared for the drainage of deep wounds, sinuous wounds, and large cavities. It is either perforated or has a continuous spiral cleft running from one extremity to the other (Fig. 220, a and b). It is introduced by means of a probe-like instrument provided with a small fork at one extremity and perhaps a handle at the other; or by means of a fine pair of long forceps. It is generally difficult to maintain in most wounds in animals, either becoming detached. by the movements of the animal or, as in the case of dogs, by being removed by the teeth. It is usually fixed in position by means of a safety-pin or a metallic suture passed through one side of it and one of the lips of the wound.

spiral wire tubing is a useful form of drainage tube (Fig. 220, c). Leaden composi tion tubing, as used by plumbers and electricians, makes, when it has received many perfora tions, an excel lent drain, as it is relatively light in weight, does not irritate, can be easily sterilized by boiling, and can be bent to any shape or angle.

Special drainage-tubes composed of rubber, vulcanite, metal, or glass are made with flanges or collars for the drainage of the chest and abdominal cavity. In consequence of their fragility and the damage they are likely to undergo by the movements or the actions of the animal, glass and vulcanite are generally unsuitable in veterinary surgery. The tube is passed into the cavity to be drained and is either fixed by suture to the wound or kept in position by virtue of the flange.

All drainage-tubes, before use, should undergo sterilization by boiling or disinfection by im mersion in a 10 per cent solution of lysol; they should be removed from time to time and sterilized or disinfected afresh. The metal ones should .be boiled for twenty minutes in water containing a small quantity of hard or soft soap, which acts much better than carbonate of soda. As the wound fills up the drain should be shortened. It may be removed altogether from those wounds which are unpocketed, free of necrotic tissue and foreign bodies, have ceased suppurating or discharging, and are on the fair way of healing by granulation.

Care should he taken that the tube does not become blocked by blood or tissue, by bending or compression, or by granulations occluding the openings.

Setons used as drains should not be left in too long, as they may cause thickening of the skin or cicatricial fibrosis around the points of entry and exit.

Drainage of the facial sinuses merely requires an outlet made at the lower or dependent part on the outer face of the bone. In the case of sinuous wounds in the region of the hoof setons may be passed after the horn has been thinned, or an opening made by passing a red-hot, thin pointed, and slightly curved firing-iron through the upper orifice and bringing the point through the outer surface of the wall or even the sole. Infected wound or suppuration of the sensitive sole of the foot may be drained by simply re moving the overlying horn.

Drainage of the uterus or the bladder can only be effected by catheterization, irrigation, and syphonage. It should be repeated within rather short intervals in order to prevent accumulation and absorption of the fluid.

The Treatment of Operation Wounds When an operation is completed the wound should be freed of shreds of tissue, which, if attached, should be snipped off with a pair of sharp scissors, and of blood-clots by gently wiping them away with a sterilized sponge or gauze pad, which may either be used in a dry state or after being immersed in an antiseptic solution and then squeezed out. If there should be any oozing of blood, firm pressure with the sponge or pad may check it, but if it still continues the wound can be washed out with a hot (150° F.) sterilized solution and pressure again resorted to. If the oozing persists after these measures, the sponge soaked in a hot saline solution should be firmly pushed into the wound and allowed to remain there until the sutures have been passed through the skin and deeper tissues. Before tightening the sutures the sponge should be removed, and if there should be any more oozing before the sutures are tightened the bleeding spot should be scored with a sharp knife a few times, or a fine silk suture passed around the surrounding tissues and tightened sufficiently to arrest the haemorrhage. If this should not give the desired result a fine-pointed, red-hot iron or thermocautery should be applied, or the wound should be plugged with dry antiseptic gauze, which should be left protruding at one end and allowed to remain in position until the haemo rrhage has stopped, when it may be removed and the wound closed.

But the tightening of the sutures passed through the skin and the tissues forming the floor of the wound generally induces sufficient pressure to arrest or prevent any small haemo rrhage without the assistance of plugs, cauteriza tions, and hot solutions.

Care should be taken in closing wounds that divided tissues of like nature should be brought together, as the end of a tendon to the other end of the same tendon, muscle to muscle, fascia to fascia, and nerve to nerve, especially those in the limbs. Moreover, it is important for a quick recovery that the tissues should be so closely approximated that no cavity or space is left for blood, serum, or pus to occupy, as such"dead spaces"remaining from imperfect contact of the surfaces of the deep tissues often prolong the repairing process of a wound, by setting up suppuration or forming deep sinuses, which should not be confounded with those set up by a deep infected suture. Both these"dead spaces"and deep infected suture suppurations account for the surface tissues, which have healed up rapidly, breaking open and giving issue to pus. In the deep or buried infected suture suppuration the pus, generally small in amount, issues from a small circular hole in the skin. In many instances it does not appear until the lapse of several weeks after the closure of the wound.

If these"dead-spaces"cannot be obliterated with sutures in conjunction with external pressure in the form of a compressing bandage, it is necessary to invoke the aid of drainage, which is seldom required in other circumstances where strict asepsis or antisepsis is observed and no irritating antiseptic solutions are used.

In the approximation of wounds made by the surgeon the size of the needle and the suture material, as silk or silkworm-gut, should not be any larger than is necessary to pass the suture and to maintain the lips of the divided tissues together in a perfect state of apposition without snapping from tension. For small wounds such as those caused by incision of the skin, as in plantar neurectomy and in abdominal operations on the smaller animals, Japanese silk of the size 00 to 1 is sufficient for the purpose, whereas in very large and deep abdominal wounds in the horse where there is much tension Chinese silk twist of No. 6 size may be necessary. It should be remembered that the larger the needle and the suture material the greater the damage to the tissues through which they pass, and in consequence the greater the chances of infection of the suture track. The needle to be used for passing through tough or resistant fibrous tissue, or the thick, leathery skin like that covering the haunch of the horse, should have a very sharp cutting point so that it can be pushed through the tissues with as little force as possible, and its short axis should be no larger than is necessary to carry the suture material with ease. As every stitch propor tionately damages the tissues and increases the chance of wound infection where strict asepsis or antisepsis cannot be assured, no more stitches than are necessary should be used.

In order to suture a wound, especially a small one, with ease and without putting the lip or flap too much on the stretch where the needle is about to penetrate the skin, a fairly large pair of thumbspring forceps with mouse or rat toothed points should be used to hold and gently raise the flap so that it is not pushed away when the needle is being passed. This method is shown in Fig. 221; it is of great assistance to the operator, and less liable to contaminate the skin-wound than when the fingers are used. In fact, there is no necessity to touch the wound with the fingers if these forceps and a needle holder to pass the needle are used. These instruments can be more thoroughly sterilized than the fingers, and in the intervals during the passage of the sutures they can be placed in a cylindrical vessel containing a 5 per cent solu tion of carbolic acid or of Lysol. Under these circumstances the closure of a wound may be performed quite aseptically. In operations on the abdominal wall under an anaesthetic a handled needle such as that of Reverdin may be used instead of a needle passed with a pair of needle forceps. Such handled needles are, how ever, very fragile, and are liable to snap when being passed if the animal should struggle. A great number of operation wounds become infected by being fingered too much at the time of closure.

In tightening the stitches before tying the knot, which should be preferably the surgeon's knot, as it is less liable to slip than other knots, traction should not go beyond the degree necessary for the lips of the wound to be brought into a perfect state of apposition, else the lips will pucker up and the degree of tension will thereby be so increased as to strangle the tissues, or to cause the stitches to cut through, unnecessarily damaging the tissues and pre venting union by first intention. In certain instances these effects nullify the success of the operation, and in intra-abdominal and hernial operations endanger the life of the animal.

Care should be taken that the lips are brought into a perfect state of apposition the whole length . of the wound, else there will be a puckering or rising of the lip, here and there, on one side or the other of the incision. Where there is ragged edge or a superabundance of tissue on one side, this should be removed or reduced to proper proportions with a strong pair of sharp scissors in order to make it equal in length with the opposite side. In case this redundancy of skin covers a large surface, as shown in Fig. 222, the reduction may be made by excising a more or less long narrow, V-shaped piece of skin at right angles to the wound, as indicated by the dotted lines in the same figure. The resulting wound, together with the original wound, is then brought together with interrupted sutures (Fig. 223). Great discrimination is, how ever, required in carrying out the excision of normal skin, as in case the wound should be infected it is liable to undergo suppuration with bursting of the flaps of the wound, so that repair can then only be obtained by the granulation of a large, gaping surface which generally in the end becomes covered to a great extent with scar-tissue, leaving a permanent blemish which greatly depreciates the value of the animal from an aesthetic point of view. Where the wound is likely to become infected it is better not to remove any redundant skin, as in the process of granulation the skin generally goes back into its normal position without leaving any slack ness, and, beyond a narrow linear scar, very little blemish. While on this subject of indelible scars it is well to point out that big sutures without strict asepsis or antisepsis generally lead to wide, suppurating stitch-tracks which result in big-stitch scars.

To obtain even approximation the wound should be put on the stretch by means of forceps, catching up the skin at each end and drawing them apart. Or, in the case of a wound of moderate length, the lips may be kept in exact apposition by holding them together between the thumb and index-finger (Fig. 224, a), or by the use of Moynihan's double-pronged dissecting or fixation forceps (Fig. 224, b) during the time the sutures are being passed.

In concluding this section it is well to direct attention to the protection of wounds made through the abdominal wall as a preliminary to operation on visceral organs as the stomach, rumen, intestine, and bladder, in order to prevent their raw surfaces becoming soiled with infective material either from the outside of the body or from within the visceral organs (intestinal con tents, infected urine).

This protection is usually afforded by cover ing the region and also the lips of the abdominal wound with an aseptic or antiseptic fabric as linen, cotton, mackintosh, or jaconet provided a with a window, the outline of which is affixed to the surfaces of the wound by means of sutures or special forceps, which may, when occasion necessitates, be used as retractors (Fig. 225).

When the closure of the wound has been completed, its surface should be freed from all debris and then dried with a dry aseptic pad before being painted with tincture of iodine, and afterwards protected with an occlusive or sup porting dressing.

Occlusive or Protective Dressing.One of the principles for the successful treatment of opera tion wounds by the aseptic or antiseptic method is to occlude the outer surface of the wound, after it has been properly approximated, by a suitable dressing to prevent outside infection, and, if necessary, to support it by an effective bandage so as to keep it in a perfect state of rest as well as to maintain the different layers of tissues in close approximation in order to prevent any recurrent hemorrhage, and to eliminate any possible"dead-space"for the accumulation of blood, serum, or pus; also to prevent any escape of visceral organs should undue tension be put upon the sutures before the wound has had time to repair.

In small superficial wounds and those made in the abdominal walls in the course of opera tions on viscera of the smaller animals the outer surface may be protected with collodion applied with a brush, and fortified or reinforced with a layer of finely-teased-out cotton-wool extending over the whole wound and beyond it for an inch or two before it is allowed to dry, and to form an impermeable covering. Such a dressing prevents any outside infection, and if the deeper surfaces of the wound have not become infected before closure, no"dead-spaces"allowed to exist, and no irritating antiseptic solutions have been used so as to produce an outpouring of serum, the wound should undergo reparation by first intention without discharge soiling the outer surface of the overlapping dressings, which may be applied to give the wound support. It is better to use over this collodion protective or occlusive dressing a firm pad of cotton-wool or peat-wool, maintained in position by the application of a bandage which should be kept on for four or five days. After removing it to examine the state of the wound it should be reapplied.

This collodion or similar protective dressing should not be used when it is anticipated that there will be oozing of blood or serum from the wound. Beyond the preliminary painting of the wound with tincture of iodine with the object of killing or inhibiting bacteria in its vicinity, there is no necessity to add iodoform or any other antiseptic or germicide agent to the collodion. Unless in the case of the addition of iodoform, the protective is freshly prepared each time with collodion made with pure ether. If the operation has been performed aseptically, simple methylated collodion will prevent infection from the outside. The animal should not be released nor the compressive dressing applied until the collodion has set by evaporation of its ether. The protective dress ing is used only with the object of supporting the wound and not for the purpose of absorbing discharge. As the collodion sets it draws by its contraction the lips of the wound more closely together. Care should be taken that the lips of the wound do not in the least gape when the collodion is applied, else some of it may enter the space between the lips and even underrun them, thus acting as a foreign body and pre venting approximation.

At the end of a week or thereabouts the bandage may be removed, and the layer of collodion allowed to separate from the skin on its own accord, when the superficial sutures may be removed.

Besides collodion, celloidin, which is pyroxylin purified by solution in alcohol and ether, is also used; and filmogen, an acetone solution of celloidin and photoxylin, a similar preparation, formalized gelatin, and a spirituous solution of shellac are also used as substitutes.

Many superficial operative wounds, and more especially those of the ears, eyelids, nostrils, or lips, after they have been sutured exude a little blood or serum which dries up into a varnish like material and forms not only a bond between the two lips but also an impermeable barrier to external influences. The scab gradually con tracts and draws the two lips closer together, and when it has fulfilled its function it falls away piecemeal and leaves a smooth surface. Such healing under a scab may be favoured by brushing the wound after it has been sutured and cleansed under antiseptic precautions with friar's balsam, which forms an impermeable antiseptic varnish; or by sprinkling on it a mixture of powdered sugar and iodoform or any other desiccating material, as powdered myrrh or a mixture of kaolin, boracic acid, and iodoform or tannic acid. Formerly the applica tion of powders, such as iodoform, boracic acid, iodine and tannic acid, salicylic acid or bismuth, was much in vogue in the treatment of surgical wounds, even those with much serous excretion. The powder was covered with lint, gauze, cotton-wool, or peat, which was kept in place by a bandage. The discharges entered into combination with the chemicals, which inhibited the growth of the bacteria found on the surface of the skin in the vicinity of the wound. This practice for operation wounds, however, has not given the satisfaction that other methods have given, and now it is rarely employed unless in the case of abrasions and other superficial wounds. Nevertheless it is often adopted in infected wounds to limit putrefaction in necrotic tissues after the surface of the wound has been dressed with alcohol or other drying agents.

Protective and Supportive Dressings.These are applied with the object of protecting the wound against the invasion of infective bacteria from the outside, of receiving any serous dis charge that may issue from the depths of the wound, and to prevent its decomposition, and above all to give support to the whole wound in order to keep its component parts in contact with one another and thus obliterate any dead spaces, and to obtain for it, as far as possible, a state of rest, which is one of the great essentials to the successful repair of a wound by first intention.

It is a much more difficult task to apply and maintain dressings over wounds in animals than in man, and in many regions it is almost impossible in consequence of the movements of the animal, which are likely to cause their displacement even when the animal does not remove them with his teeth, as often happens, unless precautions are taken to obviate this by some mechanical device. It should, however, be pointed out here that displacement or removal of the dressing by the animal should warn the attendant that the dressings are causing dis comfort or pain, that the wound is infected, or the dressings are saturated with discharge and require readjusting. Aseptic wounds, which do not necessarily imply sterile wounds or those undergoing repair by first intention, rarefy give rise to pain, discomfort, or itchiness, which attracts the attention of the animal to them.

In order to limit movement of such regions as the limbs, and also to retain dressings in such operations as suturing of disunited frac tures or divided tendons, and for the removal of old scars from the knees, splints are necessary. Any undue strain of the parts due to the move ments of the animal before repair is effected is very liable to render the success of such operations nugatory. The parts must be kept in a continuous state of apposition and absolutely at rest if successful results are to be obtained.

The best kind of splinting material for this purpose is wire-netting as used for aviaries for small birds. It can be procured in or;-inch mesh and having gauges varying from 22 to 20 and 19, the lowest number gauge being the stiffest. It can be moulded into any shape by cutting, bending, or hammering so as to fit the part for which it may be required. Windows or doors can be made into it so that the wound can be dressed through the opening. After it has been well padded and all unevenly fitted surfaces have been effaced on the limbs, it can be maintained by tapes or bandages. Woven wire, like that used in the manufacture of sieves, which can be obtained in various meshes and gauges and the component parts soldered, may also be used. No non-absorbent material such as unbleached cotton-wool should be used for padding, as such in constant contact with the skin of animals causes a desquamative dermatitis. This wire-netting forms the best and lightest material for splints or a rigid frame work for the maintenance of a dressing for any condition for which it is applicable.

Dressings applied to wounds on the limbs of the smaller animals are best maintained by a narrow (1 inch) water-dressing bandage, the turns of which should be smeared with pitch plaster (B.P.) so as to prevent slipping.

Where splints are used on dogs after suturing the non-united ends of a fractured femur or humerus, the foot should hang free for an inch or so below the lower end of the splint and be fixed so that it cannot be drawn above the end of the splint. This is necessary in order to keep the limb in a state of extension and to prevent undue tension on the suture. The splint should be applied when the limb is in an extreme state of tension, before the animal has recovered from the anmsthetic.

In those positions where a dressing or bandage is liable to become displaced by movements of the animal, leather-strapping, harness, tapes, or bandages may be applied around the trunk of the animal to prevent slipping.

Whatever dressing is used must be soft, pliable, elastic, and easily adaptable to irregular surfaces, and, above all, it must be readily absorbable and thoroughly sterilized and must not possess any irritating properties.

Many dressings, such as cotton-wool, peat wool, tow, tenax, jute, gauze, and lint, which have been sterilized and had incorporated into them various reputed antiseptic agents, such as carbolic acid, lysol, cyllin, iodoform, iodine, eucalyptus, boracic acid, salicylic acid, double cyanide of mercuro-zinc, bichloride or biniodide of mercury, or zinc chloride, are put on the market in closed tins or cartons for this purpose, but too much reliance cannot be put on their being sterile or having much germicidal power, and at best many of them only possess deodorant properties, which in the case of those carrying volatile substances they lose after two or three days of their application to the wound. This can be accounted for by what one commonly observes in the manner they are handled, often with soiled hands, even when they have not been placed on dirty tables or corn-bins or on the ground not rarely fouled with dejecta or wound discharges. It is from this manner of misusage of antiseptic or aseptic dressings that wounds hitherto treated by a more or less strict aseptic technique become contaminated, bringing reproach on the antiseptic method in veterinary practice.

Those dressings impregnated with volatile substances, as iodoform, iodine, carbolic acid, or eucalyptus, lose their antiseptic or deodorant properties, especially if they become saturated with discharges, after a few days, and if not protected by some impermeable covering, such as mackintosh, jaconet, oiled silk, glazed or tarred paper, or tarpaulin, they soon become foetid from decomposition of the albuminoid discharges. Under such circumstances they should be removed under antiseptic precautions and renewed with fresh dressings. The im permeable covering should be placed over several layers of the absorbent dressing and then covered in its turn with a layer or two of cotton-wool before applying a firm compressive bandage to include the whole.

In case of a discharge of serous fluid being anticipated, which is rarely the case where the wound is treated under strict aseptic and anti septic principles without using irritating lotions or allowing"dead-spaces,"provision should be made by the insertion of a drainage-tube or drainage material, or by leaving out a stitch or two at the lowest end of the wound, which should, when possible, be made in a direction favourable to natural drainage. Before apply ing any dressing it is better to disinfect by painting with petrol, tincture or ethereal solution of iodine the surface of the skin to be covered with the dressing. When the spirit has evaporated and the skin is dry, a layer or two of boracic lint should be placed over the wound and allowed to overlap it for two or more inches all round it. Over this lysolized or Burnettizedl tow, carded peat-wool or cotton wool for the depth of one to several inches, according to the size of the wound and the size of the animal, may be placed.

Above these layers the impermeable covering may be applied, and in its turn this is covered with cotton-wool and the whole kept in position by a firm and elastic bandage, preferably the tetra-bandage, but in lieu of this a woollen, cottonette, or water-dressing bandage. For wounds in the thoracic or abdominal region in large animals bath towelling, especially that termed"Hessian,"forms a useful bandage, which may be prevented from slipping by fixing it to a surcingle and crupper or to a collar with tapes or other suitable material. In the smaller animals the bandage can be prevented from getting misplaced by pinning it with safety-pins to a coat or waistcoat made out of a piece of calico and provided with two or four holes through which the limbs pass. For broader bandages for the large animals thin sacking is a very suitable material.

It is better, where possible, as in the case of the smaller animals, and of the lower region of the limbs of the larger animals, to apply and fix the dressing during the time the animal is fully under an anaesthetic, in the recumbent position, or before removing the tourniquet, so that the pressure on the wound exerted by the dressing and the supporting bandage, which should be moderately firm but not so tight as to strangle the tissues and cause ischaemia, prevents any reactionary haemorrhage, which is otherwise liable to, and often does, take place when the animal struggles to get up, or when on his feet, or after the tourniquet has been removed.

For operation wounds on the feet in larger animals, as that made in the excision of the lateral cartilage (Lafosse's operation), it is advisable to protect the dressing against becom ing soiled with urine and faces by enveloping the foot in tarpaulin or some other tough im permeable material, and then to enclose the whole in a leather or rubber boot.

All the dressings should be applied in a dry state, and not removed before the third day unless they become displaced, cause discomfort, or symptoms of septic fever supervene. In our patients it is advisable to remove them about this period in order to examine the state of the wound and to relax pressure of the bandage, which, as mentioned above, should in certain instances be applied with a high degree of firmness in order to prevent reactionary haemorrhage.

If there should be, by any chance, a collec tion of blood under the skin, a stitch or two should be removed and the blood-clot carefully evacuated, and after the cavity has been washed out with a sterilized 1 in 4000 solution of biniodide of mercury a stitch or two should be put in, allowing a certain space between the stitches to exist for the issue of any serous fluid that may be formed. This subcutaneous haemorrhage is known by the prominence of the skin, which has often a purplish appearance. Should there be any evidence of suppuration in a stitch track the offending suture should be removed, as also those which are too tight from swelling and strangling of the tissues, which is known by their reddish or purplish discolora tion. They may, however, be replaced by fresh ones. The relaxation, or deep-supporting, or pressure sutures should also be removed, as well as any other external sutures that have served their purpose. Before removing sutures it is advisable to wipe them and the wound surface gently with a piece of cotton-wool or lint squeezed out of a 5 per cent sterilized solution of zinc chloride, or to brush them over with tincture of iodine, so that on their with drawal they should not draw into the track any infective material. The stitch should be cut with very sharp narrow-pointed scissors close to the surface the time the knot is held with a pair of thumb forceps, and then with drawn in a manner so that the knot is not drawn through the suture track and the lips of the wound are not stretched.

The dressings should be removed and renewed in the same antiseptic manner in which they were first applied. They should be continued for four or five days longer, when the remaining sutures may be removed. Should there be any granular condition of the skin or edges of the wound the surface should be dusted with equal parts of boracic acid, zinc oxide, and kaolin, a combination which has a very reliable desic cating and cicatrizing effect. It is better to maintain the dressings and bandage until the wound has become firmly united, as until this has been effected any undue tension of those parts capable of great extension is likely to burst the wound and render fruitless all the previous care and attention that has been bestowed on the case. The success in obtaining the union of an operation wound by first inten tion depends greatly upon the care in which the first dressing is applied.

Besides the dressing materials mentioned above, rags, wool, and any other fabric having a high degree of absorbing power may be used after they have been plucked to pieces, sterilized by boiling, and then immersed in a 5 per cent solution of Lysol, cofectant, cyllin, or Burnett's fluid, and afterwards dried. Dried sphagnum moss, soaked for some hours in 1 in 500 solution of perchloride of mercury and then squeezed out as dry as possible and put into muslin or gauze bags so as to form pads of an inch or more in thickness, forms a cheap and suitable dressing for many wounds. These pads may be made up in various sizes and shapes. Peat and also sawdust put up in similar bags may be used for the same purpose.

Where no iodine has been applied or remains on the skin, several layers of double cyanide gauze may be applied over the wound, and above these layers a mass of salicylic or alem broth wool is placed and then covered with some impermeable material and retained in position by a bandage. This forms an excellent dressing where exudation from the wound is anticipated.

On those wounds where no serous exudation is expected to occur, a piece of lint soaked in compound tincture of benzoin and squeezed out as dry as possible may be applied and covered with a thick layer of cotton-wool and maintained in position by a bandage. It acts in a manner as favourable as many other modern and more expensive dressings.

Besides the dry antiseptic method of treating wounds there is the older method of treatment with wet antiseptic dressings, which are more likely than dry dressings to cause irritation and maceration of the skin and wound. The best results are obtained when the dressings are boiled, squeezed out, and then immersed in a 5 per cent solution of carbolic acid, lysol, or such like antiseptic, and immediately applied to the wound and fixed by a bandage. This is kept on for several days and renewed as re quired. It may be covered with an imperme able material. It soon becomes dry, but has the disadvantage of forming lumpy or stiff layers. Probably it is the best dressing for use in country practice. Some authorities, to prevent the antiseptics irritating the lips of the wound, cover the surface with a narrow strip of oiled silk or jaconet before applying the dressing, first gauze, then cotton-wool, impermeable covering, cotton-wool, and finally a bandage.

The simple water dressing in which lint, tow, or some other absorbent material is saturated with plain water, as advocated by Liston and commonly adopted by veterinary surgeons, does more harm than good. The same may be said of irrigations with plain water.

The wet treatment of wounds, whether by moist antiseptic dressings or _irrigations or by anti septic baths, is only indicated in septic cases. To give good results, the dressings as well as the fluids should be sterile as well as antiseptic, without producing any irritation. They should be frequently renewed or continued until the wound has become sterile, when the dry treat ment may be followed. Boiled water used at a temperature of 120° F. acts equally well. In fact, all liquids containing antiseptics act more beneficially when used at this temperature. This is particularly noticeable in septic wounds of the feet and phlegmonous conditions arising from infected penetrating wounds in the limbs, where continuous fomentations with hot water generally ward off dangerous complications. Heat applied in a continuous manner has a very high therapeutic value in the treatment of septic and painful wounds, as it has in many infectious processes.

The open treatment is that in which no dressings of any kind are applied. In general veterinary surgical practice this is the com monest mode of treating certain operative as well as accidental wounds. Provided it is carried out in an aseptic and antiseptic manner so far as instruments, hands, and surroundings are concerned, it gives very fair economical results. In castration and operations in which there is a wide dependent orifice for natural drainage and the tissues are not unduly injured by unskilful manipulation, no blood-clots are left in the wound to act as a nidus for the development of infective bacteria, and no soiled material comes in contact with the wound, the results are excellent. It gives better results in the country, especially in favourable weather, than it does in towns. It is more applicable to young and immature animals than it is to adults, whose tissues are more susceptible to adverse influences. No irritating lotions, liniments, or ointments should be used to lower the vitality of the tissues. Such a procedure should never be carried out in infected surroundings, as a lambing pen, nor in a filthy stock-yard, nor when the wind is in the east or north-east.

It is better to rely on boiled water used at a temperature of 120° F. than to trust to anti septic lotions prepared with ordinary water at the time of using. Boiled water, boiled saline solution, and other liquids should be used in scrupulously clean utensils. A teaspoonful of a doubtful disinfectant in two gallons of well water in a foul pail has neither aseptic nor antiseptic properties.

Bone Sutures. Bone suturing is generally carried out in those cases of fracture where it is difficult or impossible to keep the fractured ends or fragments in apposition by means of splints and bandages, as in fractured patella in the horse and in fracture of the femur, humerus, and of the lower jaw in the dog. It may also be used for open, especially comminuted, fractures where there is great mobility.

For the purpose of this operation an all-metal Archimedean drill of 5f to 10 inches in length, stout silver wire, and a pair of wire-pliers with a cutting edge are necessary. Holes are bored through the bone a short distance from each end, the wire passed through and the ends brought together and twisted a few times; the superfluous wire is cut off and the remaining ends flattened down to the bone. Ivory pegs, steel nails, screws, spiked plates, steel bridges, oblong, angled, and Y-plates of nickelled steel, with suitable perforation for screws, are also used for fixing the ends or fragments of dis united fractures. In certain fractures bolts with nuts may be necessary. For the insertion of screws, pegs, and nails, in addition to an Archimedean drill, an all-metal screw-driver, and perhaps a bone awl, will be required.

After the operation, splinting or some other method of limiting the mobility of the sutured part must be applied so as to prevent undue strain on the suture, which is liable to cause detachment of one of the ends of the fracture or breaking away of the suture.

The writer has on many different occasions had recourse to bone suturing in the dog with, in the majority of instances, the happiest results, the animal having carried the embedded suture many years without manifesting any inconvenience.

In amputation of a limb through a long bone after the superimposed tissues have been cut through, the periosteum covering the exposed bone should be raised in conjunction with the tissues which rest upon or are attached to it, so as to cover the end of the divided bone, after which it is brought over and kept in position with a few interrupted sutures. This periosteal flap, if it becomes adherent to the end of the bone, will preserve it from atrophy and lessen the liability to the formation of a conical stump.

Various Methods of Suturing Operation Wounds Interrupted Sutures. Simple Interrupted Suture. This is the commonest suture in use in general veterinary practice. It is made by passing a needle carrying suitable material, as silk, through the skin and subcutaneous tissue of the border of the wound, at a distance of a few lines from the edge, according to the size and depth of the wound and the tension of the tissues. The suture is then tied by a reef, or, what is better, a surgeon's knot drawn together sufficiently to approximate the edges of the wound (Fig. 226, h) without leaving anypuckering of the skin (Fig. 226, c).

The knots should be placed at one side or alternately on either side of the line of union, near but not over the suture holes (Fig. 227, B). The distance between the stitches varies according to the animal, the size and situation of the wound, and the gauge of the suture material. VVhere there is much tension, deeper sutures inserted further from the borders of the wound should be used. These sutures (Fig. 227, A), commonly termed relaxation, approximation, or tension sutures, when carried deeply through all the divided tissues and even those below them, not only relax the tension on the superficial stitches but approximate the deeper layers of the wound and thus prevent"dead-spaces"or sagging of one layer from another. They are also useful where external pressure cannot very well be maintained, as in the groin. Their employment, however, is not as a rule necessary when the various deep layers are brought together by buried sutures.

In small animals where the wound-flap is wide or involves the muscular tissue, the suture may be passed through the whole of the divided tissues (Figs. 220 and 230) and the stitches may be placed alternately so as to involve a slightly greater breadth of tissue, as shown in Fig. 228, which also shows deep pressure stitches running in the direction of the wound made in the inguinal region of a male dog for the radical cure of scrotal hernia. This system of suturing gives greater support to the lips of the wound, prevents sagging, and therefore post-operative haemorrhage, and obliterates"dead-spaces." For the closure of wounds made through the whole thickness of the abdominal wall, as in laparotomy, one layer of interrupted sutures passed through skin, muscular tissue, and peritoneum is sometimes used (Fig. 229); or two layers, one through the skin and the other through the muscular and peritoneal coats (Fig. 231). In the latter case, instead of merely passing the superficial layer through the skin as illustrated by Fig. 231, the suture may be passed through the areolar tissue, underlying muscular tissue, and not under but between the deeper sutures as in Fig. 232. Where three rows of sutures are used to close the wound, the deep or peritoneal opening is generally closed by a continuous suture, the muscular opening with a row of interrupted sutures, and the superficial or skin opening also with a row of interrupted sutures, which may be alternately passed at a greater depth of the skin than the intermediate ones, as in Fig. 233.

Sutures that include more than one layer of tissue maintain the borders of the wound in apposition much better than those which pass through a single layer. This is evident where external pressure in the form of a bandage and dressing cannot be applied, or, if applied, can not be kept in position in consequence of the movements of the animal. Objection may be urged against using embedded or deep sutures, or of passing one row of sutures over the deeper ones, an objection which is only important when the wound is closed without observing the rules of strict asepsis or antisepsis. Deep sutures favour union by first intention by obliterating"dead-spaces,"which form a receptacle for serum or secondary haemorrhage, and besides they render the part proof against hernia or prolapse.

The advantage of the interrupted suture over all others is, that if irritation or suppuration supervenes the stitch or stitches can be removed without jeopardizing the approximation of the whole length of the wound. At any time, defective stitches can be removed and fresh ones put in their place. Further, should signs appear of accumulation of blood or pus under the skin there is no necessity to remove all the stitches in order to provide an outlet.

Button Suture.This is an interrupted suture (Fig. 234) which is usually inserted deeply through the tissues, mostly as a relaxation suture, and instead of the free ends being tied together each is brought through a perforation in a metal disc and fixed. Sometimes the suture material passes twice through each button—the double button suture (Fig. 234, b). A third form of button suture is that of Bozeman, in which the suture ends are fixed on a metallic plate by means of perforated shot. Either wire or silk or other suitable material may be passed through the wound for a button suture. When perforated shot is used instead of a button it takes the name of shot suture.

Quilled Suture. This is made by passing several double interrupted sutures through the lips of the wound, half an inch or more apart, and tying the ends over a quill or rod of wood, aluminium, or whalebone, or a catheter placed on either side in a line parallel to the wound (Fig. 227, c). It is sometimes termed a compound mattress or a clavate suture. It is useful for deep gaping wounds and in deep vaginal and perineal wounds.

Twisted or Pin Suture, Hare-lip Suture. This is formed by passing a suitable pin or needle through the lips of a wound and winding thread, silk, horse-hair, worsted, or other material round the free extremities of the pin in an interrupted figure-of-8 manner (Fig. 235). Between the pin sutures small interrupted sutures of silk may be passed through the skin at the edges so as to prevent gaping of the wound. This suture may be made a continuous twisted suture by carrying the material from one pin to another throughout the suture line.

In very large wounds, where there is much tension, skewers may be used instead of pins.

The twisted pin suture is chiefly employed for wounds of the eyelid, nostril, and ear, and in the autoplastic operation for broken or blemished knee.

Three - cornered Wound Suture. In an in verted or upright T-shaped wound the two interrupted sutures cross each other (Fig. 236), or a single suture embraces the three lips of the wound so as to approximate them.

Mattress Suture. This is an interrupted suture made by passing a needle through the tissues in a transverse direction to the wound, and then recrossing so as to form a loop at one side and two free ends at the other which are tied together.

Continuous Sutures. Simple Continuous or Glover's Suture. This suture is formed by passing a needle furnished with suture material through the divided tissues, securing the first stitch by a knot, and afterwards continuously passing and repassing transversely through the whole length of the wound and finally securing the suture by another knot (Fig. 237). This suture may take an oblique direction under and a straight direction above, or a straight one under the skin and an oblique one above, the wound (Fig. 237). The latter has a tendency to cause a puckering of the skin.

Blanket Suture. - This continuous suture is made by passing the needle, armed with a suit able thread, through the lips of the wound, and, after each stitch, the thread is held down by the thumb and finger on the opposite side to maintain tension the time the needle passes through the tissues over the thread, in a"half hitch"manner. The series of"half-hitches"is tightened and maintained at right angles to the wound, whilst the portion between them takes the same direction as the wound.

Purse-string or Tobacco-pouch Suture. This is made by passing the needle through the skin for some distance, draw ing the thread after it, and repeating the inser tion until the circumfer ence of the circle is com plete, when the free ends of the suture thread meet and are tied together (Fig. 238).

This suture is useful when passed round the anus, to prevent recur rence of prolapse of the FIG. 238. Tobacco pouch rectum in the dog, cat, or suture. and pig. It is used in connection with Murphy's button and to close up the orifice after resection of the ceecum.

Subcuticular Suture. The needle, armed with silkworm gut, fine silver wire, or Japanese silk, is first passed through the skin and then the subsequent stitches are made alternately on either side. The ends are left long and pulled to approximate the wound edges in an accurate manner. When it is necessary to remove the suture one end is seized with a pair of forceps and drawn out a little and cut off; the other end is then seized and withdrawn gently (Fig. 239). It is useful for small wounds and in herniotomy.

Intestinal Sutures. In suturing the intestine it is necessary that certain precautions be observed in order that successful results may be obtained. First, haemorrhage should be avoided, and secondly, irritating or septic material should be prevented entering the peritoneal cavity. These two factors are of especial importance in equine, ovine, and feline abdominal surgery. In all species the coapta tion of the divided borders should be made with great care so that they may remain perfectly united. Shock, as far as possible, should be obviated, and the retention of septic and other irritating matter prevented.

Union of incisions in the bowel or of two portions of the viscus may be brought about by suturing alone (direct method) or by suturing in addition to the use of mechanical apparatus (mediate method). As a rule, union by the direct method takes up much time and thereby increases the liability to shock, and in order to shorten the operation the use of some mechanical contrivance is generally preferred.

The best suturing material is Japanese silk from No. 00,0, to 1 or 2, or in lieu of this, Chinese twist, which should be rendered aseptic by boiling. Ordinary milliner's needles with not too sharp points may be used. The blunt pointed needles used by harness makers and other leather workers are also suitable.

Lembert's Suture. This is an interrupted suture which passes through all the coats of the bowel with the exception of the mucous membrane. The needle passes through the wall for about to is of an inch from the lip of the wound on either side. The sutures should extend beyond each extremity of the wound. When the ends of the sutures are tied the serous surfaces are brought in contact by inversion of the lips of the wound (Fig. 240, B and c).

Czerny-Lembert Suture. This is similar to the last, with the addition of a second super ficial layer of sutures made through the sero muscular coats above those of the first layer, so that when drawn together and tied the first layer becomes buried. Originally Czerny's first layer of sutures were passed through all the coats, including the mucous membrane (Fig. 241).

Chaput's Suture's, or Sutures by Abrasion. There are three methods by which these may be inserted. Along the whole extent of the wound for about of an inch in width the mucous membrane is separated from the muscular coat. After excision or invagination into the intestine from the detached part, the first layer of interrupted sutures is passed through but not penetrating the whole thickness of the mucous membrane of the lips of the wound. A second layer of sutures is then passed through the serous and muscular coats. By this method the lips, of the mucous mem brane are inflected (Fig. 242). By the second method the sutures pass right through the mucous membrane so that when tightened the lips are in apposition.

In the third method, beyond the suture by . abrasion, there are two layers of sutures one above the other, opposing serous membrane to serous membrane.

Wolfier's Suture. This is made from the inner side and carried through all the coats of the bowel, bladder, or stomach. It is serviceable in closing a wound in the attached portion of stomach or bowel (Fig. 243).

Halstead's Mattress or Quilt Suture. This is made in a similar manner to that of Lembert, but a loop is formed at one side of the wound with the two free ends at the other, resembling in form a hairpin. The free ends are tied together. It includes the submucous mem brane.

Jobert's Suture. This is an interrupted suture passed through the whole thickness of an inverted portion of bowel and then carried through, from above downwards, the opposite lip of the wound and afterwards from within outwards in the inverted portion so as to approximate the serous surfaces in the opera tion of invagination for circular union of a divided bowel (Fig. 244).

Dupuytren's Suture. This is a continuous suture passed in a similar manner to that of Lembert, but the suture material crosses the wound in an oblique manner.

Cushing's Suture. This is also a continuous suture. It includes the submucous membrane. The suture crosses the wound at right angles, but the needle is so passed through the bowel that it takes a direction parallel to the wound. When it is passed through the other side and drawn together it inverts the edges of the wound so as to approximate the serous surfaces.

Tendon Sutures. Divided tendons are united by sutures, but there must be an entire absence of haemorrhage to obtain satisfactory results. There must be complete antisepsis, else there will be failure in reparation and perhaps a destructive inflammation of the sheaths of the tendons and surrounding tissues. Divisions of some standing as well as recent ones respond to treatment; but the sooner they are brought together the better, as the longer they are left the greater the difficulty in uniting them. When more than one tendon is divided in a wound care should be taken to unite the two parts of the same tendon.

There are several methods of suturing the divided ends of tendons. In the simplest, the suture is passed through one end of the tendon and then through the other end; in both cases about a quarter of an inch from the cut surface, and the free ends of the suture are drawn together until both cut ends of the tendon are approximated, and then tied in a knot. Another suture of a similar kind may be passed so as to cross the first suture; or it may be made in a parallel direction. The quilted suture is made by passing the needle twice in and out of the lateral surfaces of the tendon above and below the division and then tying (Fig. 245). Another method is to pass several sutures through the sheath of the tendon. Small supplementary sutures may be passed through the lips of the wound between the deeper sutures. In oblique divisions the sutures are carried in a transverse direction through the divided extremities. Where there is loss of a portion of tendon from injury or inflammation, or even a contraction without any loss, lengthening may be tried by autoplastic operation.

Chromicized catgut, kangaroo, or reindeer tendon, fine silk or silver wire may be used for the union of tendons.

Nerve Sutures.Divided nerves may be sutured by methods similar to those adopted for divided tendons. For recent division with no loss of nerve-tissue the extremities may be brought into apposition with a couple of fine catgut or silk sutures passed with a round needle and then tied. The sutures should be made as near to the surface of the nerve as possible (Fig. 246, a). They may be made through the sheath only (Fig. 246, b). Tension of the nerve at the opposing cut surfaces must be avoided.

For divisions of old standing resulting in loss of function and atrophy, the nerve ends must be exposed, stretched, and the cicatricial tissue removed. Thin sections are removed from the bulbous extremity until normal nerve tissue is exposed. The lower end is also, but slightly, dealt with in a similar manner. The two extremities are then brought together by three or four fine sutures passed through the nerve at about an inch from the divided extremi ties and tied. Where there is a loss of nerve tissue, leaving a gap between the two divided ends, it may be repaired by an autoplastic opera tion.

As suture material fine catgut, kangaroo tendon, or silk may be used. Needles similar to those recommended in bowel suturing should be employed to carry the suture material. Needles with sharp points or cutting lateral surfaces should be avoided.

Artery and Vein Sutures. In the case of partial or com plete division of large vessels, especially the main ones in the limbs, it may be necessary to approximate the divided ends so as to restore circulation to the parts supplied by them.

Sutures similar to those of Lembert in intestinal surgery are made, care being taken not to penetrate the endothelial lining. Sutures should also be passed through the areolar sheath of the vessel so as to give the sutured part support. Before at tempting suturing it is necessary to shut off the blood supply by temporary ligation or clamping of the vessel above and below the wound, care being taken in doing this that the inner lining of the vessel is not injured.

Suture and Ligature Materials.The object of suturing wounds is to hold the divided tissues in apposition until reparation by cell prolifera tion has taken place. Sutures should not be too tight, or strangulation of tissue may result. Suture material should be sterile and non irritating. It should be sufficiently strong to withstand strain without breaking during manipulation.

As a general rule, absorbable suture material should be used in deep suturing, and that employed for superficial sutures, which will be removed ultimately, should be of the non absorbable class. The latter is, however, less likely to carry infection, because it can be rendered more completely sterile.

Organic Suture or Ligature Material. 1. Absorbable Suture or Ligature Material. Catgut, which is prepared from the small intestine of the sheep, and not as its name implies from the cat, is sold in various sizes, viz. 00, 0, 1, 2, 3, and upwards, is rarely now adays purchased in an unsterilized condition, but one should be careful of the repute of the commercial house from which it is procured, as some specimens are very unreliable so far as sterility is concerned. It may be procured in three forms, viz. plain, chromicized, and iodized.

Plain catgut is more rapidly absorbed than the chromic, and as it is more pliable it is easier to tie than the chromic, which can stand more strain and does not become absorbed so quickly.

Chromicized catgut is hardened with a pre paration containing potassium bichromate. No. 2 size is used for ligating bleeding vessels divided during an operation, whereas plain catgut is mostly employed for ligating pedicles and the omentum. The No. 3 size is used for holding the divided ends of a large muscle together.

Iodized catgut is sterilized by immersing catgut in iodine, which, however, weakens its power to resist great strain. It is pliable and easily handled.

Kangaroo tendon is made from the tendon of the kangaroo. As it will not withstand heat it has to be sterilized by immersion in antiseptic liquids. It must not be boiled with the instruments.

Reindeer tendon is prepared from tendons obtained from the reindeer, and is sterilized in a manner similar to that of kangaroo tendon. Sutures of tendon are used in those conditions where prolonged immobilization of wounded parts is indicated, as in maintaining fragments of fractured bones in position and for ruptured tendons.

Tendon is slowly absorbed and does not seem to have much advantage over chromicized catgut.

2. Non - absorbable Suture and Ligature Material. gut is the fibre or gut withdrawn from the silkworm killed when it is about to spin its cocoon. It is smoother than silk and is more readily cleansed. It is not absorbed, but it is said that it is less liable to cause a stitch abscess than silk. It has no value as a ligature because, in consequence of its stiffness, it cannot be tied in firm knot. In its finer sizes it is sometimes used in place of horse-hair.

Silk is used both for suturing wounds and ligating blood-vessels. For these purposes it is sold in two forms, the twisted and the braided. It is readily sterilized, easily applied, and makes a firm knot. It is not absorbed and may be readily infected.

The Japanese have put on the market a high quality of suture silk which has been found very reliable in practice.

Silk may be sterilized by boiling with water containing 1 per cent of bicarbonate of soda for ten minutes, or keeping it for some time in a 10 per cent solution of carbolic acid. It cannot withstand repeated boiling without becoming brittle and losing its tensile power.

Silk is distinctly useful in abdominal surgery. It is sold in sizes from Nos. 00, 0, 1, 2, 3, 4 and upwards.

Pagenstecher's (celluloid) thread is made of fine hemp dipped in a solution of celluloid and is sold in hanks. It is smooth, very strong, easily handled and readily rendered sterile. It does not lose its stiffness or hardness even when kept in sterilized solutions for years, and there fore does not unravel as does silk when exposed to similar conditions. It is very cheap, relatively stronger than silk, and allows a firm knot to be made. It is largely used in place of silk in abdominal surgery. For external sutures in veterinary practice it is far inferior to silk, as it causes more irritation and often sets up stitch suppuration.

Linen thread in the form of a hard twisted black Irish linen, as well as ordinary linen sewing thread, is used in place of silk in abdominal surgery. It is sterilized in a manner similar to that of silk.

Wax Thread. Both Pagenstecher's and other linen or hemp threads may be waxed by putting them in melted paraffin wax, after they have been soaked in ether or oil of turpentine. They are then drawn through a clean cloth to free them from superfluous wax. This form of thread is supple and does not imbibe organic liquids or unduly cut the tissues.

Horse-hair removed from the tail of the horse may after it has been washed in soap and water and sterilized by boiling for an hour, be used as a suture material for wounds of the eyelids, mouth, and lips.

All these organic suture or ligature materials may be procured in a sterilized form put up in containers in which they are kept ready for use when required.

Inorganic or Metallic Suture Material. Silver wire, which may be procured in various gauges, is the best of this class for suturing purposes. It is used where sutures are required to be maintained in position for some time, such as in deep wounds of the abdominal walls, wounds in the roof of the mouth, torn eyelids, fractured patella, and in disunited fractures.

Polished or plated iron wire, as used by florists and bottling merchants, may be utilized under similar conditions and is just as effectual as silver wire.

Leaden composition wire is an excellent suture material for large and autoplastic wounds in horses and cattle. It is very soft and pliable and can easily be twisted with the fingers. it causes very little, if any, irritation. It has the advantage of being readily untwisted where one wishes to examine the depths of a wound suspected of undergoing suppuration. In case of a very large gauge wire being necessary for a relaxation suture in deep and wide muscular wounds, such as those sometimes found on the haunch where the skin is tough and thick, the hollow or tubular leaden composition cable wire, as used by electricians or telephone mechanics for soldering purposes, is very suitable as it is light and pliable. The lumen or hollow centre contains resin, but this is no disadvantage.

These composition wires, which require special needles with a tubular distal end for carrying them through the tissues, of which Reek's pattern is a good example, are often used by practitioners to close the wound after removal of a testicle accompanied by a more or less slight inguinal hernia, in order to obviate prolapse of the viscus.

Zinc binding wire, which is fairly pliable, may also be used for large wounds in which there is much tension or strain.

All these metallic sutures should be rendered sterile by boiling for half an hour in water containing soft soap, after they have been polished in order to remove all traces of oxidation. They may then be immersed in a 5 per cent solution of lysol until used for suturing.

Pins are often used to close certain wounds where pressure is required, as wounds carried through the whole thickness of the eyelid, nostril, and lip. They are also used in certain autoplastic operations such as cleft lip, cleft eye lid, removal of indelible scars from the knees, and also for the closure of the cutaneous wound in the operation of phlebotomy. In the method of arresting haemorrhage by acupressure they form one of the necessary requirements. The pins used for this purpose are the hare-lip pin, the blanket pin, and the bead-headed pins, sold by linen drapers for domestic purposes. They assist in the formation of a continuous and also of an interrupted twisted suture.

After insertion the sharp point should be removed by a pair of wire-cutting nippers (Fig. 247).

Nickel - plated steel safety pins are useful for keeping rubber drainage tubing in position at the mouth of the wound and for passing through the walls of the anus or the vulva to retain the replaced prolapsed viscus. For the larger animals they require to be of a suitable or special size. They may also be used for closing the abdominal opening after the replace ment of herniated viscera, and in addition for passing through the skin and sub-lying muscular tissue to maintain pressure of the flap so as to avoid sagging and in consequence"dead spaces"in a wound where external pressure cannot be very well effected.

Steel skewers are often utilized for closure of large abdominal openings through which a portion of the viscera has escaped from the abdomen forming an abdominal hernia. They are either passed through the muscular coats surrounding the breach or merely through the skin and subcutaneous tissues forming the sac of the hernia. They are used in conjunction with light metallic clams or cord, and left in situ until the incarcerated tissues have sloughed off.

Metallic buttons, composed of either lead, zinc, aluminium, or a metallic composition, are used to assist in the formation of the button-suture. Pugh's pattern is a very good one for this purpose.

Iron screws with sharp points, as used in joinery, are sometimes used to keep in apposi tion broken fragments, as in fractured patella, and also the disunited ends of the bone, in oblique fracture. The sizes usually used are to 1 inch.

Electro - plated T and iron plates with several perforations for the passage of screws are useful for raainta.inin.g fragments of bones, and the separated ends of bones that cannot be maintained in position by splints and bandages, in a state of approximation until reunion has taken place. Unless they cause irritation or suppuration they are not removed after the fracture has united, but left in position where they undergo gradual disintegration.

Hasmostasis, or the Control of Bleeding From whatever source the bleeding may arise, unless prevented or checked it obscures the vision of the surgeon during the operation, and unless removed before the wound is closed it forms, in the absence of strict asepsis or anti sepsis, a suitable medium for the development of bacteria. It may prevent healing by first intention, or it may endanger the life of the animal either from infection or from loss of blood.

The three principal sources of hemorrhage are the arteries, veins, and capillaries.

From the Arteries. In arterial or active hemorrhage the blood spurts out some distance in a jerky or intermittent manner from both ends, more from the proximal end than from the distal end of the divided vessel. The blood, which is of a light-red colour, is checked when pressure is applied to the vessel above the bleeding-point.

From the Veins. — In venous or passive hemorrhage, the blood, which is of a dark-red colour, flows continuously without' spurting from the distal end of a divided vein. Pressure below this point of the vessel checks the bleeding.

From the Capillaries and small Vessels. Capillary hemorrhage so-called does not alone flow from the capillaries but also from arterioles and venules. The blood continuously oozes until it ceases spontaneously in a short time.

Bleeding takes the name of primary hemo rrhage when it appears immediately or soon after an injury. Should it recur within twenty-four hours after primary bleeding has ceased it is then denominated recurrent or reactionary hemorrhage, and is due to dilatation set up by exertion which increases the action of the heart, or to the giving way of a ligature. When the bleeding appears several days after an injury it is said to be secondary, and is probably set up by the disintegration of the clot or to septic infection of the tissues surrounding the end of the artery.

Rational Arrest of Hcemorrhage. This takes place in nature by the coagulation of the blood, which increases and is due to alteration of the blood itself, as it flows; by diminution in the force of the heart's action, which is produced by the loss of blood; and by changes which take place in and around the vessel itself, such as retraction of the vessel within its sheath, contraction of the divided ends, and the forma tion of a coagulum within and around the orifice. These means may in the first instance temporarily arrest hemorrhage and afterwards act permanently. Therefore the customary practice of the layman of washing away the blood from accidental wounds and of giving a stimulant is of no advantage. Exercise or movement of any description stimulates the blood-flow and therefore should be avoided. Hemorrhage from a vessel partially divided transversely, longitudinally, or obliquely may be profuse, but it generally lessens or ceases after complete division of the artery.

The spontaneous arrest of haemorrhage from small vessels is best seen in young, healthy, vigorous animals. In old debilitated and in young anaemic and flabby animals the natural powers of overcoming bleeding are enfeebled, either from a lowered vitality of the vessels themselves or from a deficiency of the fibrin ogenous elements in the blood.

Preventive or Pre-operative Hasmostasis. The prevention of haemorrhage is chiefly applicable to the limbs and tail, and may be carried out by means of a tourniquet applied around the member and fixed so as to compress the vessels.

The tourniquets principally used for this purpose are composed of rubber tubing or cord from 18 to 20 inches in length, provided with a. hook at one end and a chain at the other (Esmarch's); with a hook at one end and a ring (Rossignol's), or a loop at the other (Leeney's, Fig. 248, a); or a block of boxwood or vulcanite with a hole or canal piercing its whole length, through which the rubber tube or solid rubber cord passes, and one or two longitudinal channels on its upper surface to fix either one or both free ends of the rubber (Foulis's, Fig. 248, A and B); or an anchor at one end to which the free end is hitched and maintained in position by tension of the rubber tubing after it has been wound round the limb in a state of tension two or more times (Samway's, Fig. 248, n). It is not necessary to have any one of these patterns, as a suitable length of rubber cording or tubing to in. in diameter wound round the limb and the free ends tied together in a knot will answer the purpose quite as well.

The tourniquet may be applied above the elbow, knee, fetlock, coronet, or hock in the larger animals, and in the smaller animals near the shoulder and hip-joints as well as any other part below these regions.

The narrow-calibre rubber tubing should not be maintained in position too long, as it is liable to injure the underlying vessels, nerves, and tissues, and may induce necrosis.

The tourniquet should not be removed until the operation is completed by ligature of the arteries, the wound sutured, or a compressive antiseptic dressing applied. In the case of certain operations it may be advisable not to remove the tourniquet until the animal regains its feet, when the compressive dressing may be applied and afterwards the tourniquet removed. If the compressive antiseptic dressing is prop erly applied very little reactionary hemorrhage results.

Unless the tourniquet be properly applied, the hemorrhage during an operation is likely to be more profuse than without it. Moreover, the limb should be raised so as to drain the veins before it is fixed else on incision some venous bleeding may occur. To render an operation absolutely bloodless, Esmarch in 1873 introduced the rubber bandage, which he firmly wound round the limb, commencing at the extremity and allowing each turn of the bandage to overlap the previous one. The bandage during its application was kept in a state of tension so as to force the blood up to the trunk, and was carried up to the region to which the tourniquet was applied, and only removed when the tourniquet had been secured. This method was introduced into veterinary surgery in English-speaking countries by Major-General Sir F. Smith, who used it in neurectomy opera tions. It is a valuable adjunct in operations where the skin and underlying tissues are extremely vascular due to inflammatory changes set up by vesicants and other causes; also in operations on the limbs of the smaller animals. It has been used with success in excision of the prolapsed uterus in the larger animals. Where local anesthesia is adopted this method of artificially producing ischmmia increases and prolongs the action of the anesthetic, partly by its benumbing effect and partly by preventing a rapid diffusion of the drug. It also prevents rapid intoxication. Unless the tension of the tourniquet when it is being applied be con tinuous, so as to compress at once both the arterial and venous circulation, venous stasis will be effected before the arterial flow is arrested, and when an incision is made there will be a flow of venous blood into the wound.

The tourniquet may be used with advantage in conjunction with long steel pins passed through the tissues to keep the rubber from slipping, as in certain positions on the fore and hind limbs and also in operations for the removal of loose subcutaneous tumours with the object of producing ischwmia. The writer has adopted this method with success in suturing the ends of ununited fracture of the femur and humerus, and found it of service in rendering bloodless operations made above the elbow-joint and the upper two-thirds of the tibial region.

Digital or mediate compression with the fingers of the chief arterial trunks supplying the operative zone with blood is rarely used, unless in those parts where other methods of pressure cannot be maintained. It may, however, be applied to arteries or veins divided during an operation.

Keeping an animal without food and water for twenty-four hours before operation reduces the liability to free haemorrhage. This is a very old practice with pig spayers and gelders, and experience proves it is well founded.

Arrest of Hcemorrhage during and after an operation is carried out by various means, such as the actual cautery caustics, plugging, pres sure, heat, cold, styptics, forcipressure, torsion, and ligature.

Hcemostasis by actual Cautery. This is one of the most ancient methods of arresting hemorrhage and is still in vogue, especially in rural practice, where it is difficult to keep the patient under close professional observation. Various patterns of irons as well as thermo cauteries are used in applying the heat. Cauterization.") The iron should be heated to a dull-red or even not beyond a black heat, as a white-hot iron chars the divided ends of blood-vessels and leaves them as rigid tubes through which the blood can still escape, whereas the dull-red iron coagulates the albumin of the vessel walls and even the blood itself, which acts as a plug to the curled-in inner and middle coats of the vessel wall. Its action is best observed where hemorrhage is arrested by clams or forceps and the effused blood is removed before the iron is applied. In presence of extravasated blood the iron quickly cools and is less likely to have the desired effect on the vessel walls.

Hcemostasis by the potential Cautery. The best-known potential cautery is solid nitrate of silver, which is suitable for arresting small haemorrhages from superficial wounds or the edges of the divided skin. It acts more effectu ally when bleeding is first arrested by gripping the oozing surface between thumb and finger or by forceps and wiping away the effused blood before applying the caustic to the wounded surface. Other caustics having a similar action are chloride of zinc, terchloride of antimony, sulphate of copper, alum, pure carbolic acid, to the vessels, and after it is finished and before sutures are inserted through the skin they may be removed after ligating the larger or bleeding vessels. Various types of artery or forci pressure forceps, such as the patterns of Pean, Spencer Wells, Doyen, Kocher, Halstead, Law son Tait, Greig Smith (Fig. 250) and Shoemaker (Fig. 251, c) are useful for the purpose; they have straight, minutely-grooved jaws, angular on the aide or on the flat (Fig. 251). They vary in length from 4E, 5, 6, to 7 inches. Some artery forceps have T-shaped jaws which are either straight, angular, or slightly curved (Fig. 250).

Torsion. This may be unlimited or free tor a and sulphate of iron. They coagulate albumin and cause a more or less thick scar which closes the orifice of small vessels.

Forcipressure. This form of arresting haemo rrhage is performed by compression of the divided blood-vessels with forceps. It is one of the quickest methods of checking bleeding during the performance of an operation. Con tinued pressure for a short period is sufficient to arrest haemorrhage of the smaller vessels, but the larger vessels should be ligated before the forceps are removed. In situations where it is difficult to ligate, the forceps may be left in situ for twenty-four hours, when they may be carefully removed without any fear of a recurrence of the bleeding. During the opera tion the hEemostatic forceps may be left attached sion, which is carried out by seizing the vessel, usually a small one, with the forceps and twisting it around a few times until its resistance is overcome. Or limited torsion, for which two pairs of forceps are required (Fig. 252). With one the vessel is seized and drawn out for a short distance, when the other pair is applied transversely so that when the forceps holding the end of the vessel is twisted a few times the pair below limits the torsion to that part of the vessel above it. The inner coats of the vessel are torn, which promotes clotting of the blood in the twisted portion.

For castration several torsion forceps and apparatus have been invented for the twisting of the testicular cord en maw.

Ligation. This is one of the surest and safest methods for the arrest of hmmorrhage from large vessels, but for the ligaturing of the spermatic vessels in the castration of the horse it is objected to in consequence of many fatal of the catgut and opening of the knot. A granny knot (Fig. 254, n) should be studiously avoided. If other tissues are included in the ligature the knot must be more firmly applied, results due to tetanus accompanying this method. Probably such untoward consequences are due to the catgut usually used being infected with the tetanus bacillus. With the chromicized or iodized catgut applied in an aseptic or anti septic manner such accidents ought not to happen, especially if the scrotal wound be sutured under anti septic precautions. The condemnation of this procedure should be due rather to the way it is carried out than to the method. The vessel is seized by a pair of haemostatic forceps, then drawn a little way from the surrounding tissues and afterwards tied firmly with the first portion of a reef or surgeon's knot before the forceps are re moved (Fig. 253). The second portion of the knot is then completed and the ends of the ligature cut closely to the knot. When cat gut is used it is better to use a reef knot (Fig. 254, A) in order to obviate the danger of the knot becoming loose owing to the welling or the ligature should be passed through the tissues around the vessel by means of a needle and then tied (Fig. 255). This latter mode of ligaturing is useful in tying the spermatic artery, mesenteric, oinental, and other vessels not easily reached by the ordinary methods. It will prevent the liga ture slipping, and thus obviate the risk of secondary haemorrhage.

Vessels in con tinuity with their normal relations requiring ligation are raised by an aneurism or neurectomy needle, which is then threaded with a ligature and afterwards withdrawn, pull ing the ligature under the vessel, which is ulti mately tied firm ly. Where an important vein is cut in a small wound the vessel is seized with a pair of forceps and withdrawn in the form of a cone and then tied with a ligature. If the wound be large both ends of the vessel must be ligated.

of ligation is useful where it is impossible to isolate the vessel from its surrounding tissues.

A round-bodied, half-circle, curved needle armed with fine Japanese silk is passed through the tissues so that the vessel is included in the ligature and tightened sufficiently to arrest the bleeding (Fig. 256).

Lateral ligation may be had recourse to in the case of an important vein. The injured part of the vessel is seized with a pair of forceps and drawn out into a fine cone, and a ligature of fine Japanese silk is then tied around the base of the cone. In case it cannot be ligatured, a few interrupted suture points may be passed through its outer coats; or even the ordinary pin suture used, as in the case of the cutaneous in cision made in jugular phlebotomy.

Acupressure. — This method of arresting haemorrhage is carried out by passing an acupressure needle or pin through the soft Fm. 256. Ligation en ?name or filopressure.

tissue at one side of the vessel, then under the vessel, and then through the soft tissue at the other side, and bringing a ligature over the vessel and tying it at both extremities of the pin. The other method is to pass the pin through the soft tissues and over the vessel so as to exert slight pressure on the vessel. If the pressure is not sufficient the pin is passed obliquely through the soft tissue at one side of the vessel, twisting it to a straight line, and then passed through the soft tissue at the other side. In superficial veins punctured in phlebotomy, such as the jugular vein, the vessel is closed by pass ing a steel pin deeply through the lips of the skin wound, which are then maintained in position by twisting a piece of silk, horse hair, tow, or cotton in a figure - of - 8 fashion (Fig. 257).

Staffordshire Knot. This is used in tying pedicles. The ligature is passed through the pedicle and needle returned so as to leave a loop at the distal end (Fig. 258, A). The loop is then passed over the pedicle and the free ends are brought one above it and the other below and then tied together with a reef knot (Fig. 258). The ligature is in the form of a clove noose, which may be used in the absence of a suitable needle (Fig. 259). Bantock's ligature is a very useful method.

Interlocking or Chain Ligatures for Pedicle,s. These are useful where much tissue would, if it were included in a simple circular ligature, become loose and slip off from shrinkage due to pressure, as in the case of the spermatic cord, omentum, or the pedicle of an ovarian cyst. The pedicle must be pierced with a handled needle carrying a long ligature having ends of equal length, and the loop of the ligature is held during the withdrawal of the needle until it is un threaded. The ligature is then divided into two halves, each interlocking one another, so that when one half is tied by a surgeon's knot (Fig. 254, c) the other half is not divided nor any vessel torn asunder (Fig. 260, A). A series of these continuous or interlocking ligatures may be made when necessary (Fig. 260, B and c).

Tamponade Plugging. In large cavities or dead spaces, where the vessels are not accessible to ligature, plugging the cavity with FIG. 259. aseptic gauze, towelling, Clove noose, or hitch.

or some other material is effectual. If possible, the material should be dry. In old veterinary practice tow was commonly used, and although it was effectual in arresting haemorrhage it generally introduced septic material into the wound, and when removed left behind some fibres to maintain sepsis. If used it should be aseptic and en closed in a sterile gauze bag. It may be iodo formized or carbolized. For small animals the alembroth ribbon gauze may be used. It should be maintained in position by passing a suture through the cutaneous wound. For the larger animals, in lieu of gauze or tow, a bath towel boiled for twenty minutes, wrung out and immersed in a 2.5 per cent solution of lysol, and then wrung out again will answer very well.

Styptics—the chemical agents that arrest hemorrhage when applied to the bleeding sur face—should not be used in those parts where there is much areolar tissue, as they are likely to cause much irritation followed by swelling and even gangrene. Solutions of sulphate and perchloride of iron, alum, tannin, resin, carbolic acid, chloride of zinc, and oil of turpentine were formerly generally used, but nowadays they are rarely applied unless for arresting hemo rrhage from the nasal and uterine mucous membranes. They act by contracting the vessels or by coagulating the albumin of the blood and producing thrombi at the mouths of the vessels. They prevent, however, union of wounds by first intention.

Adrenalin chloride applied locally will arrest hemorrhage from small vessels. Collodion painted on the lips of the wound will act simi larly. Compound tincture of benzoin applied on gauze is very useful in arresting hemorrhage in small cavities. A sponge immersed in boiled water containing 1 per cent of tincture of iodine, or 2.5 of carbolic acid, at a temperature of 120° F. and applied to the cut surface acts not only as a haemostatic but also as an aseptic. It acts by causing constriction of the blood vessels and assisting the formation of coagula. Intrauterine injection of hot water will arrest A B postpartum hemorrhage. Although cold will cause constriction of the blood-vessels it retards coagulation. It should not be applied to wounds, as it not only lowers vitality of the tissues but it introduces septic material. Also, in its secondary action or reaction it causes dilatation of the vessels. It is now generally discarded for hot water, which should never be used under a temperature of 110° F. or it will increase the hemorrhage. In passing, let it be noted that for the successful use of the actual and potential cauteries, styptics, and hot water as haemostatics, blood clots must be removed and the hemorrhage checked by pressure before they are applied.

Pressure.This is very often adopted in arresting haemorrhage from the lower zones of the limbs and also from a divided palatine artery. A tampon of tow twisted in the form of a firm figure - of - 8 applied over the bleeding region and maintained in position by means of a woollen, elastic, or Tetra bandage firmly drawn round the limb several times and then tied will generally check the haemorrhage (Fig. 261). Sometimes it is advisable to apply a second woollen bandage over the first one. The animal should be kept standing and the bandage removed after twenty-four hours. A similar tampon is applied over a divided palatine artery in the region of the bars and kept in its place by winding a narrow water-dressing bandage several times round the anterior maxillary region above and behind the incisor teeth. Instead of a tampon of tow, lint, or gauze a whole or split wine-cork may be used. For arrest of haemorrhage from the limbs of the smaller animals a narrow bandage wound round the limb, commencing from the foot upwards in a spiral manner, will generally be successful. Precaution must, however, be taken that the pressure of the bandage is not greater above than below the wound, else the haemorrhage, instead of being arrested, will flow more freely than if no means were taken to check it.

A graduated compress of several layers of material made up in the form of a cone is sometimes applied over the vessel, and main tained by pressure on the base by a bandage or strapping.

To prevent haemorrhage supervening under a wound after it has been closed, such as those in the subabdominal region, a thick pad of tow, lint, peat-wool, or cotton-wool should be so applied that when a contentive bandage is fixed and maintained the pressure is evenly distrib uted over the whole of the wound to obliterate dead-spaces, and prevent sagging and haemo rrhage from lack of sufficient support.

Needles. The needles used in general surgery are either straight, half-curved, double or treble-curved. or full-curved. The cutting sur face may be in the form of a trocar, chisel, lance - head or triangular, with flattened or bevelled cutting borders or a rounded point, like that of the needles used in ordinary millinery (Fig. 262, a to q).

The transverse section of the shaft of the needle is round, or triangular with the apex of the triangle either on the upper or lower surface of the shaft, oval, elliptical, or flattened from side to side (Fig. 262, r). They vary in length from 1 to 6 inches, but they are usually sold in sizes varying from 1 to 18; the smallest being No. 1 and the length gradually increasing as the numbers go up. In some cases, however, this order of numbering is reversed.

Hagedorn's needles are flattened from side to side, and in the half-curved and curved shapes are bent on the edge instead of the flat. The point has an oblique cutting edge which readily penetrates or pierces tough skin, like that cover ing the haunch of the horse, without much force being required. The eye is round, so it is easy to be threaded with the suture material (Fig.

262, a, h, n, and r 6). It makes a slit-like opening at right angles to the direction of the wound incision; it does not gape but has a tendency to close up when the suture is tightly drawn up (Fig. 263, a 1 and 2 and b 2). It does not, however, bear as much strain as the round or transverse puncture, which has, on the other hand, the disadvantage of causing a gaping wound on drawing together the suture (Fig. 263, a 3 and 4; b 1 and 3). It has the drawback of requiring a suitable needle-holder capable of gripping it at right angles to the holder (Fig. 264, 11).

A needle similar to this, and known as the reversed or modified Hagedorn, is flattened like the ordinary suture needle from the head to hall-way down the shank, whence it gradually takes on the form of the Hagedorn and, like it, has the flattened oblique cutting edge (Fig. 262, k). Ferguson's needles are made on a similar principle, only in the case of the curved ones they are more crescentic than semicircular in outline. Doyen's crescentic uterine needles are similar to the modified Hagedorn, only the eye is slit-like instead of being round.

The calyx-slit or spring-eyed or self-threading. needle has the advantage of being easily threaded (Fig. 262, j). Paterson's slit-eyed needle has a big eye with a narrow slit running from it to the head (Fig. 262, q). The advantage of this is the thread is firmly gripped by the walls of the slit and cannot easily slip out of its grasp.

Those needles generally used in bowel sutur ing or in suturing divided nerves, blood-vessels, or wounds of serous or mucous membranes have a round shank and point similar to those needles used in millinery or dressmaking.

Sometimes for the same purposes a flattened needle with rounded edges is used. They are straight, half-curved, crescentic, or semicircular in outline.

The needles used for carrying deaden com position or pewter wire are tubular at one end, through the lumen of which the wire is passed. Some are provided with an eye so that the end of the wire can be bent over and caught in it so as to prevent it slipping out of the channel (Reek's wire-suture needle) (Fig. 264, 3); and others have a groove so that it is possible to press out the end of the wire should it become broken in the lumen of the tube (Fig. 264, 3). Needles used for carrying silver wire are similar to the ordinary suture needles, but they are provided with deeper lateral grooves running from the eye to the head.

There are many other forms of needle, such as those used in autoplastic operations in the roof of the mouth. Most of them are in the form of a curved hook.

When suturing is carried out in deep, narrow channels, as the mouth or vagina, or in deep spaces, as the inguinal region, it is necessary to use needle-forceps, the length and pattern of which are regulated by the depth in which they are going to be used or the kind of needle they are required to hold.

Needle-holders or Forceps. —Needle - holders or forceps dispense with the necessity of requir ing various long-handled needles for suturing wounds in deep and narrow channels and spaces. In lieu of anything better, artery forceps may be used, but unless they have one or two deep transverse or longitudinal grooves in each blade the needle is likely to slip or get displaced when it is firmly opposed to the tissues through which it should pass.

The forceps figured on following page (Fig. 264, 11) are suitable for all kinds of needles, includ ing the Hagedorn; they can also be used as artery forceps. For deep abdominal operations, Doyen's long-handled forceps are very useful, as they hold the needle at any angle (Fig. 264, 7). Macphail's are also very serviceable, as they take all kinds of needles (Fig. 264, 6). They may be obtained in various lengths.

Most operators discard the need1e-holder in suturing ordinary operative wounds, preferring their fingers instead; but where strict asepsis or antisepsis is absolutely necessary for the primary union of such divided tissues, as tendon, nerve, and bone, needle forceps can be main tained in a strict state of sterilization whereas the aseptic or antiseptic state of the fingers cannot be guaranteed.

Handled Needles. Handled needles are not often used in general veterinary practice because, as a rule, of the skilled assistance necessary for their proper use not being available and of their liability to break on any sudden movement on the part of the animal. They are chiefly used in operations on the abdominal walls, in long narrow channels, or in deep narrow spaces.

The handles of such needles are composed of solid steel; their lateral or flat surfaces may be plane or concave, or obliquely or longitudin ally grooved. In other instances the handle may be in the form of a loop or ring of wire, sometimes with a thumb - rest (Fig. 264, 8, 9, 10, and 12).

The shanks are straight, long, medium, or short, half-curved or fully-curved, or bent at various angles to suit the purpose for which they are intended, such as intra-oral, intra laryngeal, or intra-vaginal surgery. In certain instances the shank is straight the greater part of its length, but towards the point it makes a swan's-neck curve, a curve almost at right angles, before making a slight second curve forwards.

The cutting surface may be oblique, pointed, or spear-headed, flattened from side to side, Those needles, either curved or straight, provided with an eye a little distance from the point are useful for passing ligature material through a pedicle in order to ligate it and prevent haemorrhage.

Some practitioners prefer a straight needle because it is more easily introduced through superficial tissues and less likely to be broken. Others prefer the half-curved. The double or treble curved (Fig. 262, b and d) or undulatory needles are said by those who have used them to be preferable to either the straight or ordinary curved needles because they give a more or less secure grip for the fingers. The full-curved needles are used in those situations where it or on the bend. They are either provided with a circular or ovular eye in the centre of the point or with a notch or slot on one of the cutting edges (Fig. 264, 5, 8, 10). In Reverdin's needle (Fig. 264, 5), which is largely used in suturing wounds of the abdominal wall, the slot for the suture material is closed by working a slide (which runs down the centre of the tubular shank) from the handle. This needle may be obtained of various curves (Fig. 264, 5, a, b, c, d).

The thumbpieces, provided on some of the wire-looped handles (Fig. 264, 8 and 9) enable the thumb to support the index-finger, which has then more power when the needle is being passed through the tissues before receiving the thread.

is not possible to use straight or half-curved ones. For most wounds, however, the writer uses them in preference to the two other forms in nearly every kind of suturing, external as well as internal. As the needles with a handle are fragile they are not economical.

Disinfection and Sterilization of the Hands. Before Lister introduced his antiseptic treat ment of wounds Lefort maintained that the hands were the chief means of conveying infec tion to wounds, and since that period a great amount of evidence has been brought forward to establish the soundness of that contention. Further investigations have shown how difficult it is to render the hands aseptic, and therefore it behoves the surgeon to take every precaution against introducing infection to wounds made in deep tissues or those in which sepsis would nullify the success of an operation even when it did not destroy his patient. In order to lessen this source of infection, the hands should be well scrubbed with hot water and soap vigorously applied with a stiff brush or a roll of horse-hair. With the object of removing the coarse and hardened epidermis, which usually harbours dirt and quantities of bacteria, after the skin has been softened with soap and water the hardened epidermis should be removed or lessened by rubbing the parts with a tablet of coarse pumice-stone. The nails should be shortened, and the loose epidermis and dirt in the subunaual spaces and that covering the matrix should be removed by scraping. After this the hands and even the arms should again be scrubbed with an etherized soap and hot water, rinsed in a 2.5 per cent solution of lysol, and allowed to dry. Painting the hands all over with tincture of iodine and allowing it to dry into the skin appears to have a sterilizing effect on them.

In the event of the practitioner having to assist in casting and fixing his patient after sterilizing his hands, he should wear wash leather gloves while so employed and again sterilize his hands before commencing the operation. Should he have occasion to place his hands in contact with any part of the body or any object that has not been sterilized during the operation, he should take the pre caution of washing them in a 2.5 per cent of lysol before they again come in contact with the wound.

When much manipulation is required in the peritoneal cavity the operator may wear thin india -rubber gloves or gauntlets which have previously been sterilized in some reliable dis infectant as an extra precaution against the introduction of infection. The objection to rubber gloves is that they interfere with tactile sensibility, but with use this may be over come.

The operator should wear a smock with sleeves turned up, or when it is a case in which the whole arm has to be deeply introduced into the peritoneal cavity, rectum, or vagina, a sleeveless one is preferable. The smock may be made of thin mackintosh, holland, or twill.

Sterilization of Instruments.Instruments like the hands, unless previously sterilized, are likely to introduce infection into a wound, and it is imperative that they should be disinfected. It is now generally agreed that the simplest and most effectual way to sterilize them is by boiling them in water for twenty to thirty minutes. It is better to place them in the sterilizing utensil whilst the water is at boiling-point. Tap- or well-water, in consequence of on mineral impurities it contains, produces on instruments during boiling deposits which discolour and, to a certain extent, injure them. To obviate this, sodium carbonate or biborate to the extent of 1 per cent, which raises the boiling-point, is added to the water. In my experience, how ever, soft or hard soap, or lysol, is preferable as it is a better detergent, and instruments left in such a solution, provided they are covered with the fluid, neither tarnish nor undergo any injurious effect. Jointed and serrated instru ments should have their crevices well brushed with soap and water to remove any debris remaining in them at the time of boiling.

Many appliances have been devised for boiling instruments, but the elongated enamelled steril izer with a perforated enamelled iron lift-out tray or a wire sieve is as effectual as and much more economical than the more expensive ones made of heavy copper, tinned inside and nickelled outside. It may be heated by gas, electricity, paraffin, methylated spirit, petrol, or by being placed on a coal, coke, or wood fire, A saucepan, fish-kettle, pail, or even a deep tin canister or biscuit box in lieu of anything better is sufficient to obtain an effective steriliza tion by maintaining instruments at a tempera ture of 212° F. for twenty minutes. In an uncovered utensil the boiling-point is not obtained throughout the whole bulk of the water, therefore a utensil with a lid is to be preferred to an uncovered one.

Smooth, nickel-plated instruments may be sterilized by immersion in pure carbolic acid for twenty minutes, and then washed in methylated spirit. Lysol may be used instead of carbolic acid. Placing instruments in an ordinary oven for an hour in a temperature from 150° C. to 165° is an effective way of sterilizing them by dry heat, but it has the drawback of rendering them liable to injury.

When instruments have been sterilized they should be placed in a 5 per cent solution of lysol before an operation, and when used they should be transferred to a 2.5 per cent solution of the same agent or, if preferred, carbolic acid of the same strength.

Sterilization of Sponges.As sponges when purchased contain grit and calcareous they should be beaten with a fiat stick until as much grit as possible is removed from them. They should then be squeezed out repeatedly in warm water and then immersed in 20 per cent of sulphurous acid, peroxide of hydrogen, or dilute hydrochloric acid. The last agent dis solves all the remaining cretaceous material in the tissue of the sponge.

They may be sterilized by placing them in cold water and gradually raising it to boiling point, when the vessel containing them should be removed from the fire, as continuous boiling destroys their texture. They may also be cleansed by thoroughly washing them in a hot solution of carbolic acid with soap, rinsing in sterilized water, and then placing them in 1 in 20 solution of carbolic acid for at least twenty-four hours, when they should be squeezed out and placed in a 2.5 per cent solution of carbolic acid ready for use.

If preferred, sterilized gauze, lint, bath towel ling may be used, or cotton-wool immersed in 1 in 20 carbolic acid solution for an hour, squeezed out and then placed in 1 in 40 carbolic solution, 1 in 2000 sublimate, or 1. in 4000 biniodide solu tion, and wrung out before applying to the wound.

Preparation for Operation. In all important operations in which urgency is not necessary the practitioner should inform his client of his conclusions, obtain his consent, and give in structions for the animal to be prepared. In many cases where time is not allowed, as in strangulated hernia, prolapse of the uterus, bladder, or rectum, compound fractures, acci dental wounds, etc., preliminary preparation is out of the question. But in the castration of cryptorchids and females and, in fact, any opera tion necessitating the use of general anaesthesia the animal should be prepared by fasting, physic, or enemata, according to circumstances. Weakly or badly-nourished animals, or those that are suffering from some debilitating disease, require to be well fed with nutritious, stimulating, and tonic diet. Old and fat animals, which are usually anaemic, should not be fasted more than twenty-four hours, and strong aperients should not be given. Strong, plethoric, and vigorous animals are benefited by fasting and an aperient. Animals that have been well fed and moderately worked can withstand a greater loss of blood. than aged, debilitated, fat, or soft horses. Again, they are less liable to shock, which may occur even without the loss of much blood.

There is less haemorrhage during or after an operation on an animal properly prepared by dieting, fasting, and abstention from water for at least twenty-four hours prior to the operation. And bacteriological examination of the blood has shown that it contains fewer bacteria after fasting than after a meal. Much of the success in castration and spaying by the older practi tioners and gelders was attributed to this practice.

In the carnivora an empty stomach is essential, in order to prevent vomition taking place im mediately after recovering from the effects of the anaesthetic. This is more likely to take place in the cat than in the dog.

The seat of operation should be freed of hair by clipping, and if thought necessary by shaving, after the part has been well lathered with an ethereal or spirituous solution of soft soap.

This latter procedure is not, in my opinion, necessary; nor is washing with a 2.5 per cent solution of lysol unless the part is very dirty. The skin may be disinfected with a spirituous, petrolized, or etherized solution of iodine, which is allowed to dry into the skin sometime before making an incision.

If the region is infected, ulcerated, or fistulous, or the seat of a suppurating wound, scraping the part with a curette and disinfecting it a few days or the evening before the day of operation should be carried out. In operations on the natural channels the mucous membrane should be washed with a warm sterile solution of bicarbonate of soda in order to remove secretions, and afterwards irrigated with a 1 to 2 per mille solution of permanganate of potassium or 5 per cent of lysol. In the case of the mouth, loosened teeth should be removed, and when pyorrhcea is present the gums, alveolar processes, and cavities painted with tincture of iodine or 2 per cent of zinc chloride.

In operations on the bowel it is difficult to assure intestinal antisepsis, but the administra tion of aperients, salines, mashes, and a milk diet is advantageous when carried out a few days prior to the operation. Such treatment not only reduces intra-abdominal pressure and dis tension of the viscera but also reduces excit ability, resistance, the liability to hwmorrhage, prolapse, hernia, rupture, and inflammatory reaction. In surgical interference with the rectum, irrigation of the bowel with 1 in 500 to 1000 solution of permanganate of potassium reduces the chances of infection.

The surface of the eye and conjunctival sac may be rendered fairly sterile by irrigation with a warm 4 to 8 per cent solution of boric acid, 1 in 1000 of permanganate of potassium or of chinosol, or 1 in 4000 of biniodide or perchloride of mercury. In the event of the conjunctival membrane or the cornea being affected with suppuration a 1 in 500 solution of nitrate of silver is the most effectual disinfectant.

In operative interference with a bladder affected with cystitis due to calculi, antisepsis may be carried out by the administration of hexamine, sodium biborate, or sodium salicylate, a purely milk diet and sedatives, such as henbane. The injection of antiseptics directly into the bladder serves no useful purpose, but is likely to do harm.

In foot cases the shoe should be removed, the hair clipped from the fetlock downwards, and the hoof pared to remove loose and dirty horn. The skin and hoof should then be scrubbed with hot water and soft soap, and afterwards im mersed in a hot solution of lysol for half an hour, and finally enveloped in antiseptic compresses enclosed in mackintosh and covered with a bandage.

Excision denotes the removal of a diseased or abnormal part by division of the healthy tissue circumscribing the diseased or abnormal. It is also used to denote removal of a healthy organ, as the ovary or testicle, or a portion of healthy tissue or structure, as a piece of nerve or tendon. When a portion of bone, nerve, bowel, tendon or any other anatomical part in continuity is excised the term resection is often applied to the operation.

The method of excision varies according to the attachments of the diseased tissue or tumour.

In the case of pedunculated tumours or tissue they may be removed by dissection. Some cysts, newly formed and retention cysts, have a very thin capsule, so great care is required not to cut into their envelope in dissecting them out. Should accidental puncture take place the capsule should be seized with a strong pair of forceps, pulled out and given a few twists, when the whole of it will come away.

In the removal of tumours or diseased glands from the parotido-pharyngeal region, the course of the jugular furrow, the axilla or groin, in order to lessen the risk of dividing important structures, as nerves or large blood-vessels, or to prevent profuse haemorrhage, blunt dissection with some dull-cutting or blunt instrument is often adopted. The blades of a closed pair of organs, as the ovary, testicle, or penis, there are no blood-vessels of importance except those in the pedicle or above the line of excision. A polypoid mass in one of the natural channels may be twisted or pulled from its base with a pair of strong forceps. The testicle may be removed by tearing, scraping, traction, torsion, ligature, actual cautery, ecraseur, emasculator, or castrator, caustic clams, rubber ring or ligature, or in the case of the young of the smaller animals by simple excision. The ovary in the mare and cow is removed by the vaginal route with a long-shanked ecraseur (Fig. 265). When tumours are very vascular and are not removed with the clamp or ecraseur, the pedicle should be sought and ligatured before the tumour is excised.

As cystic and solid tumours are separated from healthy tissue by a capsule of inflammatory scissors, a spatula, the back of a scalpel, a director or some specially devised instrument termed a blunt dissector or enucleator (Fig. 266, b, c, and e) may be used for this purpose. Where the surrounding connective tissue is plentiful and lax, tearing with the fingers, pulling and twisting at the same time may be resorted to, as in the case of some of the freely movable tumours on the under surface of the abdomen of the dog. There is very little haemorrhage from this procedure, and provided the operation is carried out aseptically or antiseptically the resulting wound repairs almost as quick as one made by sharp division. Such wounds having many little pockets on their surface and the damage of the tissues being greater, suppuration and necrosis may be severe where strict cleanliness is not observed.

In dealing with infiltrating tumours, such as the carcinomata, and sarcomata, and some forms of inflammation where there is no well marked line of demarcation between the healthy and diseased tissues, it is necessary to include in the excisions healthy tissues well beyond the line, in order to make the removal of the diseased structures as complete as possible.

Too much traction should not be made on the part to be excised in order to prevent tearing or breaking away and thus leaving behind some of the diseased tissue. A bold sweeping incision should be made without penetrating large vessels or other organs.

For the excision of small warts, those small melano-fibromata embedded in the depth of the skin, and small granulomata on the skin of the dog, the skin should be gripped below the tumour between the thumb and finger of the left hand while a pair of dull-cutting, curved clipping scissors held with the right hand cuts off close to the skin or squeezes out of its bed the new growth or inflammatory enlargement, leaving a clean raw surface which should be cauterized before releasing the skin. By this method, which is carried out most expeditiously, such growths are removed bloodlessly and the wounds do not require subsequent treatment.

For the resection or excision of nerve, the ends of a fracture forming a false joint or excision of an epiphysis, the parts are exposed and divided so as to form a breach in continuity, which may, if necessary, as in the case of bone, tendon, or bowel, be brought into continuity again by suturing, etc.

Tearing and twisting, by means of the fingers or of a pair of strong forceps, are useful pro cedures as they are followed by little if any haemorrhage. In the case of well-defined subcutaneous tumours after the skin has been divided and dissected from the upper surface of the new growth, they may be removed by tearing them from the surrounding loose areolar tissue. The advantage of this method is that should the new growth be malignant, it is less likely to leave any of the infective material behind to start a fresh growth elsewhere.

Elastic Ligature. Rubber or elastic cord passed round a peduncular tumour and tied firmly acts by continuous pressure arresting the circulation in the tumour, which undergoes necrosis and eventually falls off. In certain tumours with a rather wide sessile base, long needles or skewers may be passed through the base and the ligature tied above them in order to prevent it slipping. Rubber rings may be used for the same purpose. The elastic ligature has been extensively used in the castration of fat lambs two or three months old. It has also been used for removal of the prolapsed uterus. Other methods are more humane and give speedier and safer results.

Clams or Clamps. These are made of steel, aluminium, or wood, and are used for similar purposes to those of the elastic ligature. Except ing their use in the treatment of hernia, in preventing hemorrhage during the cauterization of pedunculated tumours and in the removal of the testicle, their employment, especially the caustic clams, is unjustifiable in consequence of the suffering they cause. This method, also termed Angiotripsy, includes crushing the vessels as well as the other tissues that are included between the blades of the instrument.

The ecraseur is a useful instrument for removing organs and morbid growths having a pedicle—as the testicle,scirrhous cord, polypi, etc.

The prevention of hemorrhage is best ob tained from an instrument provided with a wide chain having a bevelled or smooth inner cutting or crushing edge, and slowly drawn up into the barrel in the stem. If a sharp chain is employed and too rapidly tightened, hemorrhage from the divided tissue is more likely to occur.

There are two kinds of ocraseur: one, the Chassaignac (Fig. 265, b), which draws the chain up into the flattened channel in the stem of the instrument by working the handle from side to side; and the other which draws the chain up by turning the handle round and round until that portion of the organ or tissue to be removed is divided. Such are those of Miles (Fig. 265, e), Reynders (d), Haussmann (g), Sharp and Smith (f ), many American inventors, and also Dewar's (a). They should be provided with a female screw or releasing attachment which when relaxed enables the operator to draw up the chain so as to fix the tissues between the chain and the nose piece of the stem of the instrument without any tedious movements of the handle. Both the Chassaignac and those revolving on a screw are now provided with this improvement, thanks to the ingenuity of the American inventors.

Besides a chain, wire, or string, hard cord may be used for dividing the tissues. For vaginal oophorectomy in the mare an 4craseur with a longer stem is necessary. Cadiot's pattern is an elongated Chassaignac.

With the same object in view, that of dividing a pedunculated organ without haemorrhage, various patterns of an instrument termed an emasculator have been introduced for the castration of the larger animals. They are chiefly used in the standing operation. The best of this class is Haussmann and Dunn's safety emasculator. Emasculators prevent haemorrhage by crushing or sawing the tissues and dividing the middle and inner coats of vessels which curl up in the lumen before the outer coat is crushed through. They do not destroy the vitality of the wounded end of the stump, which undergoes a superficial necrobiosing process and heals almost as rapidly as a wound made with a scalpel.

Scraping, or Curetting. Scraping, or curet ting, is adopted for the quick removal of dead or diseased tissue, which might otherwise take some time to separate, and during that time infect the surrounding healthy tissues. It is also carried out with the object of removing or exposing infection infiltrating the tissues, so that powerful antiseptics or mild caustics may come in contact with and destroy the micro-organisms.

Scraping is performed with a Volkmann's sharp spoon (Fig. 266, d) or a curette (Fig. 266, a) until all the diseased tissue is removed and the healthy tissue exposed. During the scraping process the part should be irrigated or flushed with water from time to time. Any tough tissue that cannot be removed with the curette should be excised with the knife or scissors, or in the case of bone or cartilage with a gouge.

There are various patterns of sharp spoon and curette, some of the latter being made with irrigation attachments so that flushing goes on during the scraping, washing away the debris formed by the broken-down tissue.

In treating sinuses, as much of the tough wall should be removed with the knife as is possible and the rest scraped. In the case of sinuses in the region of the hoof, as much of the diseased wall should be destroyed with the actual cautery and then removed with the curette.

When being carried out on a thin - walled cavity, as the uterus, or in a large abscess cavity with a very vascular wall, or in contact with large vessels or with a wall of friable tissue, the scraping must be gently carried out in order to obviate perforation.

Where the scraped surface is small in area pure carbolic acid may be applied to it, or it may be gently rubbed with nitrate of silver. If the surface is extensive, a strong solution of sulphate of copper or zinc, or a fairly strong one of zinc chloride may be employed, taking care immediately to wash away the fluid.

In the great majority of cases of necrosis of bone I prefer natural exfoliation to curettage, as the living tissues soon loosen the necrotic tissue, which can then be removed with a strong pair of forceps, leaving behind it a healthy granular surface. In human surgery, into which tubercular or syphilitic disease of bone enters largely, curettage is extensively employed.

Punctures Puncture denotes a more or less deep wound made in a tissue, tissues, or a hollow organ by means of some sharp narrow instrument. The depth of the wound so made is very much greater than its width.

Puncture is made with a narrow bladed lancet or knife such as Paget's or Syme's, as in opening an abscess or cystic cavity; with a grooved needle or fine trocar and cannula, as in cases of exploratory puncture, hydrothorax, ascites, for allowing the escape of an effusion from the thorax or abdomen, urine from the bladder in case of retention from obstruction of the urethra, gas from the stomach or intestine in tympany; with hollow needle for the intro duction of a fluid medicament, serum, or vaccine from a syringe or a hydrostatic reservoir.

For puncturing the chest between two ribs (paracentesis thoracis) a trocar and cannula (Fig. 267, b) of 3 to 4i inches in length, about in. in diameter, and provided with a round or oval handle, is required for the horse, the shorter length being suitable for light-bred horses and the longer for heavy, thick-chested cart horses. Before inserting the instrument, which should be sharp, the skin should be clipped and dis infected and drawn to one side, so that after the operation the skin glides back into its normal position and covers the subcutaneous wound.

For small animals the writer prefers an incision through the chest wall to a puncture made by trocar and cannula. Some operators incise the skin previous to passing the trocar and cannula through the chest wall.

Should no fluid pass through the cannula after the trocar has been withdrawn, the cannula should be directed forwards or backwards, upwards or downwards, so as to break down any adhesion or to remove the orifice of the cannula from the surface of the opposing lung.

In ascites a shorter but a larger gauged trocar and cannula is preferable to the smaller gauged instrument used for pleural effusion. For the cat and dog, laparotomy is preferable to the trocar and cannula.

For exploring purposes a hollow grooved needle, hypodermic needle, or fine trocar and cannula (Fig. 267, d) pushed into the depths of a circumscribed or diffused swelling, or into a cavity suspected to contain pus, serum, chyle, or blood, enables one to make a positive diagnosis.

A very useful instrument for puncturing an abscess, cyst, or closed cavityfor either diagnostic purposes or the evacuation of fluid contents is one made on the plan of a lady's curling tongs, in which one round or convex blade fits into the concave or channelled blade of the other. The point of the convex blade is sharp and carried some little distance beyond the point of the other. The blades should embrace each other so that when closed they form a smooth cylinder with a sharp conical point. There may be an orifice near the point and another near the joint, fixing both blades together like a pair of scissors, so as to allow fluid to flow into, through, and out of the channel. After this instrument has been plunged into a cavity and no fluid escapes, the blades may be opened so as to act as a dilator.

The trocar and cannula used for relieving tympany of the rumen in the ox are usually round, having a diameter of about in. to in. and a length of 8 to 12 inches, not including in this the handle. Some practitioners prefer a flattened oval trocar and cannula. Those used for relieving the horse of intestinal tympany are about 12 inches long, * to in. in diameter, and either curved or straight (Fig. 267, a and c). For the introduction of fluids into the cavity of the viscus a cannula with the channel extending above the shield is necessary to attach a piece of rubber tubing which is connected at the other end with a reservoir, funnel, or syringe, such as a Higginson, for the reception or intro duction of the fluid. Similar means are adopted for lavage or washing out the pleural cavity, and by lowering the rubber tubing below the recipient the chest will empty itself by siphonage, which is very much less tedious than by with drawing the fluid by means of an aspirator.

Some of the caimulte used in paracentesis thoracis are provided with a short tube standing out at a right angle from the long tube, or have an oblique tube near the shield or a stopcock as in Potain's aspirating trocar and cann.ula.

A curved trocar and cannula is used for punc turing an over-distended bladder through the rectum (Fig. 267, a). By using a straight instru ment this viscus may be punctured through the abdominal wall. Abscesses or cysts, and dis tended bursts may be evacuated by means of a trocar and cannula, and through the wound made by the instrument drainage tubing or a seton may be introduced.

Cannulm that are required to be maintained in a cavity for some time are provided with a shield having perforations for the attachment of tapes to keep the instrument in its proper position.

When the cannula is being withdrawn the skin surrounding it should be pressed back to the underlying tissues so as to avoid producing a pocket for the collection of fluid. The wound should be disinfected with tincture of iodine.

Puncture is sometimes made with a pointed cylinder or sharp red-hot iron, as in cauteriza tion by points or in perforating abscesses, cysts, and other cavities. Multiple punctures with a fine knife or lancet or scarificator are occasion ally made with the object of reducing the volume of an cedematous part, as the sheath, or as a counter-irritant.

Puncture with a sharp needle (acupuncture) Is made between the ends of a disunited fracture so as to break down a lowly organized tissue and to induce reparation; also in cases of periostitis to relieve tension, as in the early stage of splint; and in spavin and other bone diseases.

Aspiration Aspiration is the evacuation of the fluid contents of a closed cavity by suction. The commonest form of aspirator is that of Dieulafoy, a syringe-like apparatus having two short nozzles fitted with stopcocks. To one of these is fitted an india-rubber tube, at the end of which is a sharp hollow needle with an opening at the point. To the other nozzle is fitted a long rubber tube to carry away the aspirated fluid, or when both stopcocks are turned on, as a siphon. In using the instrument it should be previously sterilized or disinfected, and then both stopcocks closed. The piston of the exhausting syringe should be drawn up and maintained in position by a quarter twist of the handle. The needle is pressed into the cavity to be evacuated and then the stop cock connected with it is turned on. The vacuum produced causes the fluid to flow into the vessel, which, when it is filled, is emptied after the stopcock connected with the needle is turned off, and the other stopcock is turned on and the plunger pressed down. This aspirator may be used for injection of solutions into cavities after they have been freed from their contents.

Potain's aspirator acts in a similar manner to Dieulafoy's, but instead of the aspirated fluid being drawn into the exhaust syringe it is sucked into a bottle fitted with a rubber plug, through the centre of which passes a tube formed by the blending of two tubes, each of which is provided with a stopcock. Instead of an aspirating needle one of the rubber tubes is armed with a special trocar and cannula provided with a stopcock and a side channelled slot, into which the rubber fits by a metal mount. It is advisable to have a break in the rubber tubing so that the ends may provide a position for the reception of a glass tube in order that the operator may be able to observe if any fluid is flowing from the cavity, and its nature.

For the aspiration of urine containing sabulous material or granular particles or frag ments of calculi from the bladder, Thompson's or Bigelow's evacuator may be used. But any rubber bulb syringe provided with a stopcock at its neck and inserted into the orifice in the head of a fairly large-sized gum elastic catheter with a wide opening on the surface a little distance from the apex, may do equally well in sucking out the granular material along with the urine or fluid that has been injected. Such an instrument inserted into the head of an aspirating or hollow needle may be used for evacuating fluid from cysts or bursal distensions.

For diagnostic purposes or for small cysts an ordinary hypodermic or antitoxin syringe fixed to a fairly long needle is quite useful. It is sometimes employed for the withdrawal of serous fluid from bog-spavin, thoropin, cystic elbow, and for the injection of iodine solution into the emptied cavity. This must be per formed under strict antiseptic or aseptic precautions. Aspiration is rarely used as a means of removing exudates or effusions from the chest or abdomen. In man it is sometimes employed with drainage after thoracocentesis to promote expansion of the lung and oblitera tion of the empyemic cavity. For this purpose Bryant uses a special apparatus consisting of a hollow rubber cushion in the form of a shallow cup through the centre of which passes the rubber tube which is inserted into the chest and connected with a ball syringe. The tube above the cushion is provided with a stopcock and a small portion of glass tubing.

Should the needle or cannula become blocked with pus, clots of fibrin, or other thick material it should be cleared with a fine stylet, probe, or other obtuse instrument passed through the whole length of the channel.

Aspiration of the anterior chamber of the eye may be carried out by means of a hypo dermic syringe and needle. For the removal of broken-down soft lens a special suction syringe is generally used.

Incisions Incisions are made with the object of dividing tissues for the purpose of laying out to the view of the operator the underlying structures which may require excising or removing, approximat ing or replacing in their normal position; or for the removal of foreign bodies, such as calculi, bullets, or fragments of loose bone. They are also made into the outer wall of an abscess or cystic cavity for the evacuation of its fluid contents.

They should be well planned so as to cause as little mutilation as possible, and at the same time to give the operator sufficient space to do his work with little difficulty, as in arresting haemorrhage.

Incisions are made by cutting from without downwards, from within outwards, or sub cutaneously.

They should be made with a scalpel, prefer ably one with a fused or fixed handle, which should be of smooth metal. There should be no constriction or neck between blade and handle.

The latter may be quite plain, or have a con cavity, longitudinal or transverse grooves on the fiat surfaces; or be in the form of a wire loop (Fig. 268, d) with the object of giving the fingers a better grip, and thus when wet with blood or The ordinary scalpel is generally held in three ways: first like a pen (Fig. 270, a), second like a dinner knife (Fig. 270, b), and third like a violin bow (Fig. 270, c).

The first position is that usually adopted in 4 antiseptic fluid prevent slipping (Fig. 268, a, b, c, d, e). The back of the blade should be straight and fairly thick until it reaches a short distance from the point, when it should gradually slope until it meets the thin cutting edge.

For. a very small incision a small, narrow a bladed knife is best. For incising the coverings of the testis in castration and the abdominal wall in spaying, most practitioners prefer a short bladed knife with a straight back and a short curved cutting edge. The handle .rests in the palm of the hand and the blade is so gripped that only one-third or at most half of the blade is left uncovered (Fig. 269).

dissection of the cadaver, but it, like the turning of the sharp edge from the depth of a wound and cutting upwards and outwards to the skin, should not be used in operative surgery. In making an incision downwards, as in castration, cutting down on a tumour or on to an artery in continuity, the skin should be made tense and the knife held perpendicularly so as to penetrate the subcutaneous and even fatty tissue; the handle should then be lowered and the incision extended by drawing the convex part of the cutting edge steadily along. Unless the tissues are very tough, a sawing action should be studi ously avoided. Another method of preventing the skin slipping while an incision is being made is for an assistant to roll up a fold of skin and hold it in a state of tension between the thumb and index finger of each hand, the incision being made between the two. Or the operator may use the index finger and thumb of his left hand as stretcher and pressor while he makes the incision from between the thumb and finger with his .right hand.

It is bad practice to have the superficial incision longer than that in the deeper parts of the wound. The incision should be the same length the whole depth of the wound. As the incision is being made deeper the structures forming the more superficial parts of the lips should be held apart by means of special forceps or a ligature passed through each lip and tied in the form of a loop, by retractors, or by forceps with serrated or toothed points, to prevent the tissues slipping from their grasp (Fig. 271, a and b).

In making incisions in the more superficial operations, as in plantar neurectomy, thumb or spring forceps (Fig. 272) with serrated or claw bite jaws, commonly termed mouse- or rat tooth forceps, are very useful to hold fascia which is to be removed or incised near the point grasped. The scalpel should be held nearly at right angles to the forceps when the incision is made, especially when important structures, as blood-vessels or nerve, lie immediately beneath the line of incision. Such forceps are also very useful to hold the lip of the wound when the suture needle is being passed through it.

In the division of deep fascia over important structures which should not be wounded, it may be necessary to catch up and lift with a pair of toothed forceps (Fig. 271) a piece of the tissue and make a small hole through it for the passage of a grooved director (Fig. 274), and to carry the back of the knife which is gently pushed along the groove while the sharp edge is dividing the tissue. Some surgeons discard the director and hold the fascia in tension between two pairs of toothed forceps while cutting it between them. Where the tissues are very loose under the fascia a probe-pointed bistoury (Fig. 268, 2 and 4) guided by the forefinger of the left hand on the point may be used instead of a director. The blunt- or probe - pointed bistoury (Fig. 268, 2 and 4) is a useful instrument for the incision of fistulae or sinuses from within outwards, and so is the sharp-pointed straight or curved bladed bistoury, but the latter should be used in con junction with a director (Fig. 274, a) or grooved sound which is passed down the course of the sinus so that the back of the knife can glide down the groove and thus avoid injury to structures lying behind the deep wall of the cavity (Fig. 273).

Incisions may be made with scissors (Fig. 275). Small incisions for the passage of setons through the tough skin of the horse or ox may be made with a rowelling bistoury, while a fold of skin is held between thumb and index finger of the left hand.

Scissors, especially those with rounded, bluni points, are useful in incising the outer wall of sinus or cavity, and lengthening incisioni already made with the knife, especially thos( through the muscular and serous walls of the abdominal cavity. For this latter purpose the3 must be very strong and powerful.

The direction of incisions varies. The linear or straight incision is most in use it should never be made transversely to the course of important structures such as vessels nerves, tendons, muscles unless circumstances necessitate it. On the other hand, it should bi in a direction favourable to natural drainage it case of need. When made to expose deeper parts the lips of the wound thus formed are helc apart by retractors, forceps, or dilators.

The T, inverted 1, L, V, and crucial + incisions are useful as preliminaries in the forma Lion of angular flaps, which when reflected enable the operator to see the exposed, underlyiN parts, and to carry out further surgical inter ference, as in the removal of tumours, excisior of bone as by trephining, etc. These incisions are commonly made in autoplastic operations it the vicinity of natural cavities and other parts.

The elliptical, 0 or almond-shaped anc circular incisions are made as preliminaries t( the excision of the tissue included within their 3ircumference. The former is generally made over the surface of large tumours, inflammatory 33rstic enlargements, and around indelible scars, especially in front of the knee, so that the ncluded tissue is removed, in the first two nstances with the growths, so that when the ips of the wound are approximated by sutures here is firm pressure and no sagging over the wall of the cavity made by the excision; in the ast case to remove the scar and then to bring the lips of the wound together by autoplastic methods, as in Cherry's operation for broken Knees practised and improved by Vinsot of and others.

The circular incision is commonly made on he skin covering the antrum and the frontal;inns; the skin included in the circle is dissected )ff (excised) so that the bone is exposed for the trephine. In circular amputation of a limb or Aber cylindrical organ the incision is carried a, director and aneurism needle; b, probes; c, drainage tube introducer.

round the whole circumference of the part to be excised.

The semicircular, the U-shaped or U-shaped incisions are made with a view to raising flaps of skin in removing or amputating a portion of a limb.

A transfixing incision is made by passing a long, narrow-bladed knife through the fleshy part, so that its point comes out at the opposite side of a limb to be amputated. The knife should be passed through close to the bone, and then the back turned to the bone and the soft part divided from within outwards in an oblique direction so as to form a flap. After one flap is made the knife should be passed through the needle with a sharp point, which is passed obliquely into the thickness of the skin (Fig. 277, c). It is used to introduce a local an aesthetic, which does not always remove sensi tiveness of the thickened or inflamed skin when introduced subcutaneously. Further it is used to introduce carbolic acid or drugs into the other side of the bone, and the process repeated so as to form another or opposing flap. The ;ubstance of the derma in follicular scabies and )ertain other skin diseases.

Hypodermic injection is carried out in a, similar manner, and by the same means with the;ame objects in view. It is used for the intro luction of local anaesthetics, diagnostic bio ogical products, sera, solutions of non-irritating alkaloids, and sometimes irritating mixtures or two flaps brought together by sutures form a covering for the stump.

Injections These are made with the object of introducing drugs, sera, vaccines, viruses, fluids, and nutrients into the system, or of removing by irrigation excretions, exudates, sera, and morbid secretions from cavities.

They are introduced into the thickness of the skin, beneath it, into muscular tissue, serous cavities (thorax, pericardium, spinal canal, and joints), the nasal chambers, trachea, oesophagus, stomach, intestine, bladder, urethra, vagina, uterus, and blood-vessels.

Intra - dermic injection is made by a hypo. dermic syringe provided with a short, hollow FIG. 277. Illustrating three directions of passing the hypo dermic needle through the skin or into the tissues.

oblique; b, vertical; c, very oblique.

oils. The needle used is generally longer than that used for intra-dermic injection, and may be passed through the skin either in a very oblique or vertical direction into the subcutaneous, areolar tissue (Fig. 277, a and b). Submucous injection is made into the submucous areolar tissue, such as that beneath the conjunctival membrane of the eyelid, as in the palpebro conjunctival test with mallein or tuberculin, or into the sub-conjunctival areolar tissue covering the eyeball, for the introduction of a solution of iodine or biniodide of mercury (potassio-mercuric iodide) in the treatment of specific ophthalmia in the horse.

Intramuscular injection is made through a long needle. It is adopted for the introduction of drugs such as quinine, strychnine, veratrine sulphate, mercury, arsenate or antimony com pounds which usually cause too great an irrita tion leading to suppuration when injected into the subcutaneous areolar tissue.

Intravenous injection or infusion of solutions into a vein may be carried out by the use of a serum syringe provided with a suitable hollow needle passed into the vein in an oblique manner (Fig. 277, c) towards the heart. Care must be taken that it is not passed through both walls of the vein or the fluid may pass into the peri vascular areolar tissue and set up irritation, suppuration, or sloughing. After the vein has been raised by pressure on the cardiac side the needle or cannula should be passed obliquely, and when it enters the vein blood will flow through the needle. In the horse and ox intravenous injection is usually made into the jugular vein; in other animals, into the auricular, facial, or external tibial vein. If a syringe is used the fluid must be injected slowly in order to avoid sudden overpressure in the right heart. When it is allowed to flow from a container held some distance above the animal the fluid falls in by hydrostatic pressure. Care must be taken that air is not allowed to enter the vein in order to prevent air-embolism or perhaps intra-cardiac hyperpressure, which may cause sudden death. In lieu of these instruments a vein may be raised or taken up and then incised and the fluid injected by a quittor, glass, or other suitable syringe with a fine pipe previously sterilized by boiling. All material to be infused should be sterilized beforehand.

Sera, artificial serum, weak solution of formalin, solution of chloral hydrate, plain water, solution of iodide of potassium, or of barium chloride, cannabis indica, chloralose, veronal, and other rather insoluble hypnotics may be introduced into the circulation in this manner. Intravenous injection has the advantage over the other methods of injection of producing prompt or immediate action of the introduced drug.

Transfusion of blood from animal to animal of the same species is rarely had recourse to in veterinary practice. But in the case of valuable animals suffering from idiopathic anaemia following some infectious process, or from trau matic anaemia due to loss of blood occasioned by an injury, parturition, or a surgical operation, there is no reason why it should not be used more than it is, especially as the donor or animal supplying the blood can readily be obtained.

The blood may be introduced directly from one animal (the donor) into another (the re cipient), or indirectly by the introduction of defibrinated blood.

In direct transfusion the blood from the donor is carried to the recipient by sewing together the ends of two severed blood-vessels in a manner that when the blood is allowed to pass there is no leakage from the union, the flow is uninterrupted, and there is no clotting. It is, however, a very tedious operation and requires care. The cannula method of blood-vessel anastomosis has replaced it. For details of both operations the reader should consult Crile's classical work on Hemorrhage and Transfusion.

Indirect transfusion with defibrinated blood was recommended by Panum of Copenhagen in 1865 as a means of lessening risk of the intro duction of clots into the circulation. During the last three decades it has been displaced by the use of simple saline solution, which is more readily obtained and safely introduced.

Normal saline solution may be safely intro duced subcutaneously, intraperitoneally, intra tracheally, or by the stomach in the herbivore, or by the rectum in all species.

Hypodermoclysis, or the introduction of fluid such as normal saline solution, horse-serum, or other therapeutic agent under the skin by means of hydrostatic pressure, is a very safe method, and is largely used in anemia and shock from loss of blood, in gastritis, enteritis, toxmmia, and septicaemia. In shock, adrenalin is often added to the physiological solution.

The fluid is placed in a glass container or douche apparatus, which is fixed to a wall or held three or four feet above the animal, to which it is connected by means of rubber-tubing provided with a pinch-cock and fitting on to a long serum needle, which is passed obliquely under the skin where there is much loose areolar tissue, notably behind the shoulder in the horse and anywhere along the back in the dog (Fig. 278).

The fluid, which falls by its own weight, should have a temperature 4° to 10° F. above that of the animal's normal temperature; it should be sterile and not irritating to the normal tissues. As much as a gallon of fluid may be introduced at one time and repeated when thought advisable—this is for the horse; for the dog, up to a pint or more according to the size of the animal.

The injection should not be repeated at the same spot until two or three days have elapsed, so as to avoid causing undue irritation. It may be mentioned that in the dog unsterilized tap-water when infused into the areolar tissue does not cause any palpable injurious effect.

Enteroclysis, or the introduction of normal saline solution or other therapeutic fluid into the bowel, is a very useful method to adopt in dysphagia, gastritis, gastrotomy, enterotomy (small intestine), in shock, loss of appetite. The bowel should be emptied, if possible with an enema.

The fluid should have a temperature of 110° F., and no more than the animal can bear comfortably should be in fused at one time, else it will be expelled. Irritating material should be mixed with some bland mucilagin ous material, as linseed or starch mucilage. The ab sorptive power of the rec tum and colon is very great.

The slow in

troduction of fluid by hydro static pressure is preferable to the method of introduc ing it by forcible means.

In the herbivora great of saline solution and other therapeutic fluids may be introduced into the stomach by means of an oesophageal tube, passed through the nostril or the mouth, attached to a high container or even a funnel.

In the carnivora this method is useful for stomach lavage in gastritis, in gestion of poison, gastric tympany, and overloaded stomach.

Intraspinal in jection is made with the object of introducing weak solutions of local anesthetics, as cocaine hydro chloride, novo cain, and espe cially stovaine, into the spinal sheath in the lumbar region for the purpose of anesthetizing the posterior part of the abdominal region and hind quarters. The injection can also be made in the cervical and dorsal region, but strychnine should be added in order to prevent disturbance of the heart's action.

This method is, however, not without danger, and the mortality from it is greater than that from general anaesthesia. For practical pur poses in veterinary surgery it is inferior to general anesthesia, and requires greater skill and much more care to carry it out successfully. For further details see the section dealing with ANIEsnirrics.

Intratracheal injection is used to introduce medicaments into the trachea and bronchial tubes, as in parasitic bronchitis (hoose, husk, or gapes), purpura hzemorrhagica, gangrenous pneumonia, and in chronic laryngeal irritation causing a persistent or chronic cough; also for the purpose of rapidly introducing a quantity of normal saline solution or even plain sterilized water into the system in collapse from profuse haemorrhage. Chloroform injected into the trachea rapidly destroys life in a painless manner.

Injections of sterilized water, saline solution, iodine solution, etc., may be made into the thoracic and peritoneal cavities. Fluids— nutrient, medicated, or macerating—may be injected through a cannula passed through the abdominal wall into the stomach or intestine.

Injections or irrigations are made into the nasal chambers and sinuses, the Eustachian tube and guttural pouch, trachea, nasal duct and lachrymal canals, conjunctival sacs, mouth and salivary ducts, oesophagus, stomach, and rectum, including the anal pouches, the vagina and uterus, the sheath, urethra, and bladder, and the cavity of the external ear; into the pleural, pericardial, and peritoneal cavities, and also into deep and sinuous wounds, abscesses, cysts, and bursal distensions, with the object of removing excretions or secretions or of intro ducing caustics, antiseptics, astringents, seda tives, or anesthetics.

In the cestral female injection of semen col lected from the male is made into the vagina or uterus with the object of inducing artificial impregnation, and anticonceptic fluids, such as quinine, sulphate of zinc, chinosol, or perman ganate of potassium, are injected to prevent conception from a misalliance.

Injections are made by means of syringes which force the fluid into the channels or cavities, or by irrigators, which are reservoirs containing the fluid, which falls or flows by its own weight through rubber - tubing provided with special nozzles.

These reservoirs, made of glass, earthenware, wood, or metal, are placed some distance above the height of the animal; they are either pro vided with an outlet at the bottom or at one side towards the base, to which the rubber tubing is affixed. In lieu of special reservoirs any vessel such as a pail, tub, jar, or even a tin canister may be used, as the fluid can be siphoned off by allowing one end of the tube, which has been weighted, to fall to the bottom of the vessel, and the other and longer part to fall over the side of the vessel. In order to prevent kinking or compression of that part of the tube meeting on the upper edge of the vessel it should be provided with a semicircle or U -piece of hard rubber, glass, or metal tubing. The flow is started by aspiration or sucking the end of the outflo wing or longer tube.

In irrigation of the uterus of the larger animals, as the mare and cow, the fluid should be withdrawn by siphonage soon after its introduction, in order to prevent its retention and absorption. A suitable apparatus for this purpose is a long rubber tube provided with an aspirating bulb similar to that of Higginson's syringe.

In the smaller animals, as the cat and bitch, the uterus may be emptied of fluid by raising the fore parts of the animal and compressing the abdominal walls towards the pelvis or by giving the animal a run. By this method a retained afterbirth may be evacuated. The temperature of the injected fluid should be from ten to twenty degrees higher than the normal temperature of the animal. Whether the fluid be forcibly injected by a syringe or allowed to inflow by its own weight, care should be taken not to force in air. This can be obviated by expelling fluid through the nozzle before the tube is passed into the uterus.

For continuous irrigation of the limbs a special nose - piece, provided with a series of outlets and capable of being fixed round the limb by means of a strap, is necessary. For deep, septic wounds one or more perforated tubes are essential; these pipes or tubes should come directly in contact with the walls of the wound, and in those wounds with a wide outlet they should be covered with pads of lint, spongio piline, or some other absorbent material (Fig. 279). For intermittent irrigation the outflowing rubber-tubing should be provided with a pinch cock to regulate the flow (see Carrel Treat ment under section of Sodium Hypochlorite in article on"Antiseptics").

The syringes generally used for the injection of open cavities, channels, deep wounds, or sinuses are of the simple kind, composed of a barrel enclosing a piston connected with one or three finger-rings, a handle, or finger-piece at the external extremity, and a nozzle or nose piece through which the fluid is forced. They are made of glass, metal, or vulcanite. They vary in capacity from two drachms to a quart. Certain of the smaller syringes of the simple kind are, however, provided with a glass barrel and metal or vulcanite mounts and pipes.

The larger syringes for enemata are generally provided with a thick, smooth pipe or nozzle. This pipe, which may be of brass, pewter, tin, wood, or vulcanite, varies in length from 4 to 16 inches according to the size of the syringe. A syringe for the larger animals should have a capacity of a quart, and one for the smaller animals, as the dog and cat, should contain from 4 to 10 ounces. Syringes with a metal plunger should be preferred, as those with leather plungers frequent ly require repacking and frequently cause much inconvenience. Read's enema pump, with a long suction-tube and an outlet tube of several feet of rubber, gum elastic, or spiral metal tubing provided with a pipe for the is commonly used as an enema syringe. When the long outlet tube is fixed on the suction extremity of the pump it acts as an aspirating pump to empty the stomach of fluid con tents. Read's pump may be used for irrigating the nasal chambers, the uterus and bladder, or for withdrawing fluid from these organs.

Higginson's pattern of syringe is composed of rubber, and provided with a vacuum ball and valve. It forms an instrument for the adminis tration of enemata, for irrigation of cavities, channels, and wounds. When supplied with rubber-tubing and a suitable nose-piece at the inlet end it acts as an aspirator; and with a hollow needle or cannula, for the evacuation of cysts, effusions in cavities, etc.

Any simple syringe having affixed to it a catheter, hollow needle, or cannula may be used as an aspirator when the air in the barrel has been exhausted.

For deep wounds and for cavities such as the uterus and bladder, fluids should not be forced in under too great pressure nor in large quantity unless through a double tube, as instances have come under the immediate notice of the writer where sudden rupture of the viscus has occurred from neglect of these precautions.

Warm or even hot solutions are generally more efficacious than cold ones, notably in case of acutely inflamed mucous membranes. For injection of quittors, small wounds, and small whilst those composed entirely of metal hide the contents so that the operator cannot observe the progress of the injection. In consequence of these objections syringes composed of a glass barrel and metal mounts are preferred. The component parts being detachable, they may be taken to pieces for cleansing and sterilization. Syringes provided with vulcanite mounts, piston rod and plunger cannot very well be sterilized without damage, and therefore should be dis carded.

The plunger should be composed of asbestos, rubber, or preferably metal, never of leather or cotton. The capacity of the barrel varies from 2, 4, 10, 15, 20, 30, 40 to 100 c.c., the graduation being engraved on the outside of the glass cavities and channels a brass syringe of one or two-ounce capacity and fitted with a suitable pipe or catheter may be used. For injection of the anal glands in the dog the pipe should be -of small calibre and have a fine, bulbous extremity. For the nasal duct the pipe should be in the form of a fine catheter and passed up the nasal extremity of the duct or down the lower lachrymal punctum. In animals other than the horse the nasal duct can only be irrigated from the lower lachrymal punctum.

For the introduction of medicaments, dia gnostic agents, curative and preventive sera and vaccines into the veins, depth of the tissues, and closed cavities, various patterns of special syringe with hollow needles or cannulm are used. Those made of glass are too fragile, as the slightest movement on the part of the animal during their use is liable to fracture them, barrel or on the piston-rod. For injection of a quantity of fluid or serum under the skin or into a vein, a length of 4 to 6 inches of rubber tubing with fitments at each extremity is often used in order to do away with the rigidity of the instrument, to prevent breakage of the needle, or an accident owing to sudden move ment of the animal.

Roux's syringe (Fig. 280) is a very reliable instrument, and is constructed so that its com ponent parts may be detached and submitted either to wet or dry sterilization. The gradua tion is engraved on the piston-rod, which carries a rubber plunger, fixed by means of a double grooved-headed screw. The plunger may be tightened or expanded by turning the head of the piston. The glass barrel is absolutely detachable, and as it is plain it is not very costly to replace if it should be broken.

Roux's syringe is economical in price and is usually sold with a number of rubber rings, plungers, and glass barrels. When the syringe is not in use the parts should be relaxed and put away in a sterilized condition. Before being used again a few syringefuls of sterilized carbolized water should be sucked up and pumped out, in order to soften the rubber fitments and to discover leakage of fluid or air.

For general veterinary use the"Record"syringe is one of the best, as it is simple in structure, and with proper care it is not liable to get out of order (Fig. 281). The mounts are adherent to the glass barrel, which has the graduations engraved on it. The plunger is of solid metal and accurately fits the glass barrel. Immediately after use the plunger should be withdrawn, or the fluid left in the barrel and on the plunger in drying may fix the plunger to the barrel and render the instru ment useless. In the sterilization of this syringe and, in fact, any syringe having a solid metal plunger, the plunger must be removed, as on cooling the glass barrel contracts much more rapidly than the metal plunger and in con sequence may fracture. Syringes like this one with adherent metal mounts or with soldered parts cannot be sterilized with dry heat, as the soldered parts give way.

Hollow needles varying in length from I to 3 inches and of various gauges are made, the shorter ones being useful for intradermic, hypo dermic, and intravenous injection, and the longer ones for deep intracellular or intramuscular and also for intraspinal injection. They are usually curved for intratracheal or intraperitoneal injec tion. For tough tissues a needle in the form of a small trocar and cannula may be necessary.

The finer the calibre of the needle the easier it pierces the tissues, but it is very fragile and it may be broken if the animal move suddenly during the operation. The needle points are either lancet-shaped, trocar-pointed with a lateral orifice or two, or more or less chisel-shaped, or they may be truncated like the point of an ordinary cannula. Immediately after use they should be boiled and then dried before the stylet is replaced and they are put away. Subjecting them to a high temperature or keeping them too long in the flame destroys the temper of the metal, and when it does not cause unsoldering of the head it renders the point soft and blunt.

If syringes and needles cannot be cleaned for some time after their use, it is a wise pre caution to place them in a wide-mouth bottle containing a 5 per cent solution of lysol, which not only cleanses them but also prevents the steel rusting.

When exhausted of air these syringes may be used as small aspirators for emptying cysts, the bladder, and other closed cavities of small animals.

Setoning Setons are used for making a subcutaneous wound either to set up irritation and produce suppuration or with the object of causing counter-irritation. They are used sometimes as a means of draining a sinuous or pocketed wound or a cystic, hemorrhagic, or purulent cavity such as inflammatory bursae (capped elbow, capped knee), poll-evil, fistulous withers, hemorrhage into a lymphatic space (heenia toma in intermuscular space of the external ischio - tibial region), and parotid abscess (strangles). They are often used to drain sinuous wounds of the coronet and also as counter-irritants in certain conditions of the foot. In the treatment of gathered nail or its effects they sometimes produce a marvellous result, the lameness disappearing after other methods of treatment have failed.

As a means of setting up counter-irritation setonmg is less used than formerly, but for drainage it is still one of the most serviceable in veterinary practice. The seton is much less likely than tubing to be displaced by the move ments or the teeth of the animal.

Seton needles are generally straight, semi circular, or more or less curved. They vary from 1 to 18 inches in length and are either flattened from front to behind or from side to side, or Fig. 282,a), or sharp (Fig. 282, b); and sometimes )evelled on the margins (Fig. 282,c). Some French patterns are made up of two, three, or four sections which when screwed together form a ong needle, the stem of which is usually oval n diameter, straight, provided with a slit-like;ye at each end and a bevelled and thin cutting )oint (Fig. 283, a).

The needle used for frog - setoning is full )urved, flattened on the curve or from side to a oval in diameter. They are about to inch in width and usually have an oblong eye either in a transverse direction or following the long axis of the needle; this eye may be either at the head or within a short distance from the point. Some needles have an eye at both ends. The point is blunt or probe-pointed with a ridge running in the centre of the upper surface side, with an eye at one end (Fig. 284, b). That used for dewlap - setoning of young cattle is slightly curved on the flat, with an eye at either end and a bevelled angular cutting-point; it is about 7 inches in length (Fig. 282, c).

For small setons or for passing large - size suture material, such as narrow linen or fibre tape, through large wounds, the labia of mares, cows, and sows, or the walls of the anus, to prevent recurrence of prolapse of the uterus, vagina, or rectum, the small long-curved seton needle of Gerlach (Fig. 283, b), with an oval eye in the thin, flat, sharp cutting-point, is a very useful instrument. This needle is also useful for setoning in dogs and other small animals.

The blunt needle may be used for passing a tape through sinuous wounds or suppurating cavities in order to form a drain, hut when it is required to pass a seton through intact skin, incising at the points of entrance and exit must be made with a sharp scalpel, rowelling scissors (Fig. 283, c), or a bistoury. The advantages of a blunt-pointed needle is that when it is being passed through it is less likely than a sharp needle to pierce important tissues. When much force is required to pass the needle a handle may be attached to it and fixed by means of a small thumbscrew or other fixing attachment (Fig. 282, d) . For long sinuous wounds, instead of a seton-needle, whale-bone probes of various lengths, and provided with a slit-like eye at one end for tape, may be used as seton carriers, and are preferable because of their relative flexibility. For curved sinuous wounds the French S-curved metal sound may be used to pass the seton (Fig. 283, d) . It is a very useful instrument and is provided with grooved ex-. tremities, each of which with an eye, and it can be disjointed into two pieces. The curved grooves form a director or cannulated sound.

The sharp-cutting, pointed seton-needle may be pushed through the skin, but care should be taken when it is forced through the deeper tissues that it does not divide important struc tures such as tendon, nerve, or blood-vessel, or penetrate a joint.

In frog-setoning the horn should be thinned at the point of entrance of the needle, and the needle should enter the frog midway between the apex and the bulb and emerge at the hollow of the heel. The ends of the tapes should be tied together, and dressed daily. The wound should be kept clean and any underrun horn should be removed in order to allow the escape of pus. The seton should remain in as long as lameness is present.

Material for Setons. The material used for setons is usually tape, which may be either medicated with iodoform or introduced plain, and afterwards dressed from time to time with oil of turpentine, terebene, carbolized oil, or blistering ointment. The tape is made of un bleached linen or of fibre. Thin lamp-wick or lamp-cotton, and for small animals, string, cord, silk, or worsted, may be used. Plaited horse hair forms an excellent material for drainage purposes; it does not cause so much irritation as the tape formed of vegetable material.

The seton should be dressed from time to time to disinfect it or to maintain irritation according to the case, and sometimes the tape should be replaced by a fresh one.

If left in too long it is liable to produce necrosis of the skin, and eventually fibrous thickening and retraction. As soon as the seton tract becomes prominent the tape should be removed, the wound disinfected, and, if necessary, a fresh seton inserted.

The seton is maintained in position by making a bow-knot at each end or by tying the two ends together. Precautions should be taken to prevent the loop being caught and torn out by the animal.

A rowel is a disc-shaped piece of leather or felt—like a gun-wad - inserted beneath the skin to create an issue over the diseased part. The rowel is perforated in the centre and two threads are attached to it for the purpose of moving it when in position. The rowel, dressed with an irritant, is bent double and inserted through a small opening made in the skin by rowelling scissors—which are provided with a hook designed for making the space within the incision for the accommodation of the rowel, which is flattened out after insertion. From time to time the rowel is rotated in position by means of the threads. It should be kept in place for about a fortnight, and after its removal the wound should be disinfected as may be required.

Firing or Actual Cauterization Firing or actual cauterization is a method of treatment which is carried out by means of an instrument termed the firing - iron, which is heated to a degree that will, when brought into contact with the tissues, coagulate their albuminous constituents, producing an acute inflammatory condition or destroying the ana tomical elements themselves.

There are various forms of cautery, some of which are heated by placing the head, composed either of iron, steel, or copper, in a fire, and others which have the heat generated by combustion of volatile fluids, as benzol, petrol, or ether, con tained within the hollow of the stem.

The ordinary firing-irons are formed of a special head connected with a fixed or detachable handle, or a cylindrical iron stem. They vary in length from 12 to 30 inches. The head is continuous with the stem either in a straight line or at right angles; sometimes the stem meets the centre of the back or base of the head as in the searing-iron used in amputation of the tail of the lamb, or in the centre of the vertically cylindrical head as in that used in docking horses.

The head has a thickened base and generally a thinner penetrating edge or point; it is either hatchet-shaped, in the form of a semilunar turf cutter, a more or less pointed or obtuse cone, bulrush - shaped, or like a sharpened pencil. The instrument used for penetrating sinuous wounds in the coronary region of the foot to make a counter-opening for drainage purposes has a fine-curved or straight point gradually tapering from the stem.

These irons, shown in the accompanying illustration (Fig. 285), are heated to a red or white heat in either a wood, charcoal, coke, or coal fire, or in a small gas, paraffin, or petrol stove, lamp, or furnace as used by plumbers.

Besides these ancient firing-irons there are special self-heating cauteries with various shaped heads, from a fine cylindrical point to that of a chisel or hatchet, made of platinum, copper, or steel, heated by volatilized ether, benzoline, petrol, gas, or electricity. Some of these, such as that of Paquelin, La Place, or the Zoo cautere, require an attached rubber bellows to force the unheated vapour into the carburettor to be heated. Others, as that of Dechery and that of Beach, volatilize the spirit automatically after the neck and head have been started by being heated over a spirit-lamp.

Platinum or copper-point cautery attach ments may also be heated by means of a bichromate battery, or by an electric light ac cumulator charged from a dynamo, from the electric light main, or other source of direct current electricity, but as these methods of heating are very expensive they are generally precluded from veterinary practice.

Small cautery points of various shapes, made of platinum or of spiral-shaped porcelain, may be heated from the main after the current has passed through a transformer or rheostat. They are attached to a special handle provided with a thumb and two finger rings and also a trigger, which, when drawn continuously, starts and maintains the current. It is connected to the transformer by means of a positive and a nega tive wire. The handle, when fixed up with a snare cannula through which a loop of steel wire is passed, acts as an electric cautery ecraseur, and is especially useful in canine and feline practice.

The transformer or rheostat may also be used for small surgical lamps; but the more powerful ones are suitable for either galvanism, faradism, or electrolysis, and also for higher candle-power lamps.

The specially constructed larger cauteries, capable of being heated direct from the electric or gas main, are suitable for firing or actual cauterization of the larger animals in veterinary infirmaries in towns where gas or electric light is ready at hand. In the case of the electric cautery the apparatus proper is connected to the plug by means of long wires, and that of the gas-heated cautery by means of a long rubber tube fixed to a tap in a gas-pipe receiving its supply from the gas-main. Both these instru ments are made on the principle of the plumbers' electrically or gas-heated soldering-iron.

For linear firing, excision, or haemostasis the various forms of the ancient firing-iron heated in a fire or a stove, with the exception of the larger cautery irons heated by direct supply from the gas or electric main, are superior in action to the modern automatic apparatus, whose points generally cool too rapidly when in contact with the tissues for efficient use.

For coarse or heavy horses with thick skin a heavy and thick-headed iron is necessary, but for well-bred and young horses in which the skin is thin or very sensitive to irritation a thin or lighter iron is preferable.

The smaller irons as used in human surgery are suitable for canine and feline practice.

For penetrating point - firing, superficial or deep, the best instrument for this purpose is Dechery's automatic firing apparatus, as it makes a narrow puncture and as deep as the point will allow if one desires it. It is less likely to blemish than the large conical-headed irons used in former days by British veterinary practitioners, and it also does away with the trouble of re peatedly heating such irons, which rapidly become cool. It is an excellent instrument for deep puncture-firing in canine practice.

The temperature at which a cautery should be used depends altogether upon the object in view. If it is to be used for its counter-irritant and destructive effect it is best employed at a high temperature, as from a bright red to a white heat. When used as a haemostatic the cautery should not exceed a dull-red heat, or the blood-vessels may be rendered too rigid before a proper clot is formed, and haemorrhage may continue or recur. When used at a black heat the tissues are liable to adhere to the iron, but this can be prevented by applying a little lard or oil to the tissues before using the iron.

As a general rule the pain caused by a bright red or a white-hot iron applied to the skin is momentary; it is not much more than a sharp twinge. This is explained by the fact that the nerve terminals in the superficial layers of skin are rapidly destroyed. On the other hand, an iron at a temperature just below that of a dull red heat does not char the superficial layers of skin, but powerfully stimulates, so that serum is poured out and perhaps the albuminous con stituents are coagulated, and it causes great pain which lasts for some time.

The cautery should not be used in the early stage of inflammation, nor when there is sup puration or any oedematous condition. It is indicated in long - standing, deep - seated, in flammatory conditions of the joints, bones, and tendons, especially when accompanied by thickening of the parts affected, by great pain and much lameness. It is then an efficient counter-irritant and analgesic, and stimulates the reparative process into greater activity. Its action is similar to, but much more powerful than, that of vesicants or other revulsives.

For chronic articular and osseous inflamma tion deep - point firing with a fine - pointed instrument such as Dechery's is preferable to line-firing. The points should penetrate the skin and reach the periosteum, which should be pierced. Care should be taken not to open an articular cavity. The punctures should not be too close together, as the intervening skin would be liable to undergo necrosis and cause a per manent blemish; they should not extend beyond the part affected.

In the case of chronically inflamed and thickened tendons, ligaments, or bursae, line firing, with the addition of a few penetrating points in the actual tissues involved, acts very beneficially by easing or removing pain, stimulat ing the reparative process, and, after the parti ally divided skin has cicatrized and contracted, by forming a firm support to the damaged tissues. When a fine and rapidly-penetrating pointed iron is being used on tendons care should be taken to avoid penetrating blood-vessels or damaging nerves. In line-firing the lines should not be too close together, nor should the entire thickness of the skin be divided. The lines should not run into one another nor be crossed so as to isolate parts of skin, as sloughing is liable to occur.

Before firing a limb the hair should be removed with a clipping machine in order to prevent the hair catching alight and obscuring the view of the operator, and in those cases where the skin is thickened and greasy the part to be operated upon should be well washed and scrubbed with soft soap and hot water so as to remove as much as possible of the dirt and loose horny epithelium. With the object of removing sensation from the part, and therefore preventing the animal resisting the operation, an injection of a freshly-prepared 5 per cent solution of cocaine hydrochloride should be made along the course of the sensory nerves above the site to be fired fifteen to twenty minutes before commencing, and renewed if necessary during the process of firing.

To prevent undue fatigue on the part of the operator in firing a horse in the standing position, well-balanced firing-irons with rather long stems are preferable to short ones, which are best for the arrest of haemorrhage, castration, and the removal of peduncular new growths. They should be heated to a white heat and have the loosened scales removed by rubbing them on a slab of soft stone, or by means of a rasp, and as soon as they begin to appear black they should be returned to the fire to be reheated. Some practitioners start with an iron heated to a dull red heat to mark out the lines, but as a white heat causes less pain it should be preferred.

Horizontal or oblique lines about three quarters to an inch apart, commencing from above and gradually working down the limb, should be made if the part be the metacarpal, tarsal, or metatarsal region, care being taken that the lines do not extend to the flexure of the knee or hock, nor to the anterior surface of the metacarpal or metatarsal region, where the bone is subcutaneously situated. In the phalangeal region it is better to make the lines in a vertical or a vertically oblique direction, but it is not advisable to continue them into the hollow of the heel.

The cautery should be held firmly and drawn lightly through the lines several times until the required degree of cauterization is obtained. If only a light degree of firing is desired this will be known by the lines appearing of a yellowish tint, rather shallow in depth and narrow in width. When a moderate degree is the aim it will be recognized by the lines having a wider and deeper appearance, a light browetint, and issuing a reddish serous fluid. Should deep firing be deemed necessary the iron is drawn over the lines until the lines appear very wide and deep, as if the whitish tissue at the bottom of the furrow were attempting to burst through with an abundance of serous fluid.

After the operation has been accomplished, many practitioners apply a cantharides or biniodide of mercury ointment or a mixture of equal parts of these two to the fired parts with the object of maintaining and increasing the irritation. But in the case of a well-bred and young horse with delicate or tender skin this is a very risky procedure, and often results in sloughing of Adn with indelible scars or blemishes. In such cases it is therefore not wise to apply a vesicant until the acute inflammation has sub sided, and then only after the parts have been washed and freed from the accumulated dis charges. As pain and irritation occur in the cauterized part, the animal may gnaw or bite, or even rub the inflamed skin, and to prevent this the animal should be tied up on the pillar reins or have a cradle put on his neck.

Twelve hours or so after the operation, the parts, especially of the limbs, swell, discharge a thickish, yellowish, resin-like serous fluid, which is irritant, and often more or less large vesicles appear on the skin between the lines. Should the animal appear restless and the swelling be very tense, it should be smeared with carbolized oil, or dressed from time to time with lead lotion or dusted over with dry dressing. When the inflammation set up by the firing has gained its maximum the parts may be irrigated or washed with cold water so as to remove the accumulated discharges and to act as a sedative astringent.

In a few days, should the inflammatory reaction not be of the degree required, the parts may be well anointed with a vesicating ointment con taining from 8 to 12 per cent of biniodide of mercury, or one containing from 12 to 20 per cent of cantharides, or in the case of well-bred, irritable horses, mylabris, which has a good vesicant action, but does not make the animal restless. The blister should be applied with friction continued for a quarter of an hour or more so as to ensure thorough penetration of the skin.

Should there be intense inflammatory re action, evidenced by excessive swelling, pain, and profuse suppuration, it should be subdued by irrigation with cold water, preferably from a hose-pipe.

In chronic arthritis of the hock, pedal, or coronal joint, or in periostitis, point-firing is more efficacious than line-firing, as the cauteriz ation is brought to bear directly on the tissues involved, and does not cause so much pain nor liability to disfigurement. It is better carried out by a fine-pointed instrument such as the Dgchery automatic apparatus than by the old fashioned, clumsy, conical-pointed iron which quickly cools, necessitating repeated heating, and making a large circular puncture in the skin. Point-firing with Dechery's apparatus is an excellent method of producing counter-irritation in chronic articular disease, ostitis, and rheu matic arthritis in the dog. The part or region, usually the shoulder , hip-, or stifle-joint, is rendered insensitive by a few injections, made at various depths, of a 2i per cent solution of cocaine hydrochloride or other local anesthetic.

As in the case of the horse, the punctures in firing must not be made too close together. The punctures may be anointed with mercurial ointment well applied, care being taken that the superfluous ointment remaining on the skin is wiped off. The writer can testify to the efficacy of this treatment in chronic inflammatory changes in the vicinity of the hip, stifle, shoulder, or other joints after all other methods of treat ment for months had failed.

This system of firing, long carried out in France, is also very effective in the reduction of bursal distensions, but care should be taken to avoid puncturing the serous cavity.

The straight cylindrical pencil - pointed iron having a diameter of an ordinary lead pencil is useful for puncturing the wall of cysts or abscesses, cauterizing chronic sinuses, or for the arrest of hemorrhage. It is also useful under certain precautions for the penetration and destruction of chronic suppurating anal glands and the soft fungating adeno - carcinomata in the substance of the anal walls so commonly encountered in aged dogs.

In the removal of the testicle the iron should be of a black heat, but in order to prevent the tissues adhering to the iron, lard or green oint ment is smeared on the cord just above the clam or clamp. The degree of cauterization employed in this method is more likely to prevent Immo rrhage than that obtained by the use of a red or white - hot iron, which chars the tissues, renders the vessels rigid or brittle, and leaves a foreign body in the wound. Moreover, the risk of secondary haemorrhage is increased. The black-hot iron coagulates the albuminous con stituents of the tissues, which curl up and occlude the lumen of blood-vessels. This is very notice able in the castration of fat lambs about two or three months old, which bleed much after being castrated by a red or white-hot iron, and many succumb from malignant oedema or gaseous septicaemia arising from decomposition of blood clot remaining in the scrotal wound.

Amputation of the tail in lambs is often effected by a cautery shaped in the form of a spade. By this means haemorrhage is pre vented and a barrier raised against invasion by virulent bacteria. H. G.

wound, fig, suture, skin and needle