SURGICAL DISEASES OF THE URINARY APPARATUS Anatomy of the Urinary Organs of the Horse. We propose to preface this article with a few remarks on the structure and positions of the various parts of the urinary apparatus of the horse, followed by a short description of the urine of the different domestic animals. The more important anatomical differences met with in animals other than the horse will be men tioned in due course.
The kidneys, or glands which secrete the urine from the blood, are encased in fat, and situated one on each side of the spine immedi ately under the loins. The tubes which convey the urine to the bladder are called the ureters. Each ureter leaves a large cavity in the kidney, called the pelvis, at a notch on the inner border of the gland, and passes backward almost in a straight line to enter the upper wall of the bladder near its neck. The openings of the ureters into the bladder are not far apart, and through these openings the urine constantly trickles into the bladder. The latter organ is seldom empty, and, according to the amount of distension, it projects more and more beyond the pelvis into the abdominal cavity. When it is not distended with fluid the urinary bladder lies on the floor of the pelvis beneath the rectum (back bowel) of the male, and the vagina (passage) and uterus of the female. In large animals, therefore, the bladder is easily reached and felt when the hand is introduced into the bowel or passage; while, in the smaller species, the distended viscus may be manipulated through the lower wall of the abdomen a little in front of the entrance to the pelvis. Lastly, the urethra is the tube, or canal, which conveys the urine from the bladder to the exterior of the body, namely, the extremity of the penis in the male, or the vagina in the female. These four parts comprise the urinary organs—the kidneys, the ureters, the urinary bladder, and the urethra. The kidneys. Although the common form of the kidney is such that the expression"kidney-shaped"is in general use, the right and left glands are far from being similar in shape. The right kidney of the horse bears considerable resemblance to the heart on a playing-card, while the left, longer than the right, is more or less bean-shaped. The glands also occupy different positions, the right being situated under the upper part of the last two ribs and the first bone of the loins. The left kidney, on the other hand, lies farther back, nearer the middle of the spine under the last rib and the first two or three loin bones. Except in large horses and cattle, it follows that the left kidney, sometimes termed the"floating kidney,"can be readily felt when the arm is inserted to its fullest extent into the rectum. In consequence of its loose attachment this kidney may sometimes be found nearer the pelvis, and in cattle it may be pushed a little to the right side of the 'spine when the large stomach is distended with food or gas. When enlarged as the result of disease it may be possible to feel both kidneys through the bowel, although the left organ is more easily reached. The structure of both kidneys is the same. Covering the surface is a fibrous capsule which can be stripped off easily in health. If the gland is cut through in a horizontal direction it will be seen to be made up of three distinct areas: (1) the pelvis, or cavity near the notch on the inner border, into which the small tubes of the kidney empty the urine; (2) a pale red area surrounding the pelvis; and (3) a thick dark-red area under the capsule dotted with dark points which are just visible with the aid of a magnifying glass. This dark-red area is very richly supplied with blood, and contains the structures concerned in the secretion of urine. The pelvis may be said to act as a reservoir for the urine; it is continuous with the ureter, which conducts the fluid to the bladder. The bladder, when empty, forms a thick, fleshy, muscular mass which lies on the floor of the pelvis. In this condition in the horse it is about the size of a man's fist. It has been estimated that the distended bladder of the horse is capable of holding nearly a gallon of urine. When full, or nearly so, the organ is ovoid in form with the broad end, or"fundus,"directed forwards, while the narrow posterior end, called the neck, is con tinuous with the urethra. The neck of the bladder is surrounded by muscular fibres which are able to contract and close the outlet for the urine. The expulsion of urine is brought about by the contraction of the muscular wall of the bladder. The urethra in the male extends from the neck of the bladder to the free ex tremity of the penis. It is the common passage for the semen secreted by the testicles as well as for the urine. The first portion of the tube in the horse is only some four or five inches in length, and it lies within the pelvis; it then turns round the bony arch under the tail at a very acute angle, which not infrequently obstructs the passage of the catheter. The urethra now runs along and within the under portion of the penis, ending in a free projection about an inch long at the end of the penis. The penis commences at the bony arch under the tail, passes forward between the thighs, and ends in the expanded extremity known as the glans. The portion in front of the purse (scrotum) can be readily. protruded from the sheath (prepuce) in which it is ordinarily lodged. In the horse the glans penis is large, and shaped, during erection, like the rose of a watering-can. At its lowest part there is a deep notch, or groove, in which the urethra projects slightly as a free tube. The prepuce, or, as it is commonly termed, a double fold or turned-in portion of skin, the inner layer of which is reflected on to the penis. It thus forms a tubular cavity for the anterior free portion of the penis. The orifice should be large enough to admit the hand in order to withdraw the penis and cleanse the sheath. When this is the case the horse is able to draw or extrude the penis with ease. Not uncommonly, however, a dirty penis, or a collection of sebaceous material in the prepuce obstructing the urethral opening, sets up irri tation and straining, with more or less difficulty in passing urine. Gross neglect may also, in hot weather, lead to the formation of maggots in the prepuce. Nevertheless, a certain amount of dark-coloured, unpleasant-smelling, sebaceous material is quite natural. Being largely com posed of fat, it serves the purpose of a lubricant.
The Urine.The urine secreted by the kidneys varies greatly in health and disease, both in the individual and in animals of different species.
So many diseases of the urinary organs depend for their detection on an examination of the urine that some knowledge of the changes which occur in health is desirable. The varia tions depend largely upon the nature of the food and the temperature. It is a well-known fact that more urine is secreted at rest than at work; and the quantity is also greater in cold weather than during the warm summer months owing to the increased activity of the skin and the amount of perspiration. A horse receiving an ordinary ration secretes about 82 pints per day, but this quantity may be considerably increased. The horse's urine is generally thick and turbid, and of a yellowish or yellowish-red colour which assumes a brownish tinge on stand ing. The urine of a mare in season is distinctly oily. Roughly speaking, urine contains water, urea, colouring matter and mucus, and salts in proportions which are of interest chiefly to the analyst. Quantities of lime and potassium salts are present in the horse, while phosphates abound in the dog and pig. As compared with the horse, the urine of the ox contains more water; it is clear and yellow in colour, and the quantity varies from 10 to 40 pints daily. In vegetable feeders like the horse and ox the reaction is alkaline; in the pig it is either acid or alkaline according to the nature of the food; while the dog's urine is always acid in health, pale-yellow or straw-coloured, and the amount varies from one-half to two pints daily according to the size of the animal and the food. The reaction of the urine is easily tested with ordinary litmus paper. Thus, acid urine turns blue litmus paper red, and alkaline urine turns red litmus paper blue. It is well to remember, however, that urine undergoes rapid changes when exposed to the air, or allowed to decom pose either within or without the body. Hence a fresh sample should always be obtained in a clean bottle. Whenever suspicious symptoms of urinary disorder are manifested, the value of making an examination of the urine cannot be too strongly emphasized. Although the analysis must be made by an expert, it may be necessary for the owner or attendant, in the absence of veterinary assistance, to take a sample and forward it to the laboratory. An analysis of the urine is extensively employed in human medicine to establish the existence of certain diseases of the urinary apparatus, in spite of the fact that the patient is able to render considerable assistance by describing his symptoms. The veterinary surgeon has, of course, to rely entirely upon his own powers of observation; and experience has shown that an examination of the urine is the only reliable means of diagnosing kidney trouble. The best method of obtaining urine for this purpose is by passing the catheter.
The Passage of the Catheter.Catheters are hollow tubes for introduction into the bladder, made either of metal, indiarubber, or other flexible substances. In using the catheter certain precautions require to be observed to avoid injuring the urethra and infecting the bladder, and even the ureters and kidneys; for it is easy to introduce micro-organisms by employing a dirty instrument, or one which has not been properly disinfected. The operation is a simple one, and may have to be performed in an emergency by the attendant on any domestic animal. It is practised in order to empty and wash out a distended bladder; to inject fluids into the urethra; to locate a calculus (stone) or a stricture; or merely to draw off a little urine for the purpose of analysis. In all cases the metal or rubber catheter should be boiled for fifteen minutes before use, the gum elastic tube being freed from grease and soaked for an hour or two in a strong antiseptic solu tion, e.g. 1: 20 watery solution of carbolic acid. The penis is drawn out, and, like the hands, washed and disinfected, and a little olive-oil, carbolized vaseline, or boracic ointment is smeared on the instrument. The best lubricant for rubber tubes is known as"K.Y.,"and consists of a mixture of gum tragacanth, gly cerin, and carbolic acid. For male animals, in which some little difficulty may be met with, the catheter should be flexible, and made sufficiently rigid by the introduction of a cane or whalebone stilette.
For the Horse, the tube should be about four feet long and one-third of an inch in diameter. The end which enters the bladder should be solid and provided with one or two lateral openings, while the other end may be expanded to fit the nozzle of a syringe, or furnished with a suitable connection. We have made frequent use of a long human stomach tube, made of rubber, fitted with a funnel of the same material for irrigation purposes. A variety made of plated, spiral steel wire, not unlike ordinary gas tubing, is also employed. The horse is usually in the standing position, the twitch is applied, and the off fore-foot is picked up. Hobbles on the hind pasterns are seldom required. The oper ator, standing at the right flank, soaps his hand, withdraws the penis, grasps it with a cloth, and gently pushes the instrument onwards until the point reaches the bony arch under the tail and appears quite prominent under the skin. Here the urethra bends round at an acute angle into the pelvis, and offers some resistance to the passage of the catheter. At this stage the stilette is withdrawn several inches, and an assistant presses the point of the instrument round the bend and into the pelvis. The stilette is again pushed home and the bladder is reached. Sometimes the hand is introduced into the emptied rectum in order to guide the catheter, but no force should be employed in pushing the instrument forward. On entering the bladder all resistance is overcome, and a steady flow of urine follows the withdrawal of the stilette.
In the Ox the penis is longer and much smaller than in the horse, and the extremity is pointed. Just behind the scrotum nearly one foot of the penis is bent upon itself in the form of the letter S. The double curve, which only dis appears during erection, offers a well-nigh im passable barrier to the passage of the catheter, unless it becomes possible to draw out the penis and obliterate the bends in the urethra. The difficulties of the operator are increased by the long narrow prepuce, with its small external opening, through which it is difficult to pass two fingers. Only those who have attempted to seize and draw out the penis can appreciate the obstacles which have to be overcome. The most opportune moment is immediately before, or after, copulation, when the bull's penis may be seized with a cloth and drawn well out, so as to obliterate the curve and enable a catheter of suitable size and length to be introduced. Fortunately, it is seldom neces sary to pass the catheter in the ox, for pressure on the distended bladder from the rectum will frequently give relief. Another method, how ever, can be adopted by the veterinary surgeon. This consists in making an opening into the urethra about a handbreadth behind the scrotum, through which the catheter is easily pushed on into the bladder.
The Ram's penis presents the same S-shaped curve, but the urethra projects an inch or more form the free extremity of the penis in the form of a very small, tapering, twisted tube called, from its resemblance to a worm, the"vermi form appendix."In order to pass the catheter the appendix must either be cut off or opened on its under surface. Another method is to incise the urethra behind the curve, as in the ox, but this is more difficult to accomplish in sheep.
In the Dog flexible catheters made of rubber or gum-elastic are employed, generally the latter. Sometimes a metal instrument is used for the detection of urethral and bladder calculi. The ordinary gum-elastic human catheter is in general use, especially the smaller sizes one to six; but a large animal like a St. Bernard requires a catheter about eighteen inches long, which is about twice the ordinary length. As a rule the operation is quite simple, if it be borne in mind that the penis of the dog, like that of the cat, is provided with a bone in its anterior portion, which is grooved on its under surface for the lodgment of the urethra.
Only small tubes can pass through this bone without difficulty. Just behind the bone there is a large rounded"bulb,"behind which the prepuce must be drawn with the finger and thumb. Again, close to the bladder, the urethra is enclosed in a large gland, called the prostate, which is frequently enlarged in old dogs, and offers obstruction to the passage of the catheter, besides interfering with urination. In such cases the finger should be introduced into the rectum to guide the instrument. The animal is placed on his back with his left side towards the operator, who observes the simple pre cautions already mentioned. If progress is arrested at the bony arch near the tail, the wire stilette with which the instrument is provided is withdrawn a short distance to enable the point to curve round into the pelvis. As soon as the bladder is entered it will be found that all resistance is overcome, and the removal of the wire is followed by a steady flow of urine.
In the male Cat the introduction of the catheter—always a difficult matter—can only be accomplished in the following manner: Take the smallest, human, metal catheter, straighten it out, or, better still, use a special, straight, metal instrument of very small dimen sions about the diameter of an ordinary probe and six inches in length. A flexible tube is useless. Place the cat in the same position as the dog, or on its left side; extrude and grasp the penis with the left hand, and push the instrument, previously warmed, oiled, and dis infected, perpendicularly downwards towards the bony arch at the entrance to the pelvis.
The penis containing the catheter is then slowly bent backwards until the point of the catheter is directed forwards between the thighs, and pushed on into the bladder. In man a curved metal tube is employed; other wise the procedure is much the same.
In the Mare, owing to the short, wide urethra, with its large opening on the floor of the vagina a few inches within the passage, the catheter can be introduced more easily than in any other animal. Two fingers, or more, can be inserted into this opening. Almost any straight, or slightly curved, tube can be passed into the bladder, if care be taken to press it forward along the floor of the passage, and to guide the point into the urethral opening with the finger. The extremity of the tube, which is usually made of metal, is furnished with a rounded"blind"end near which there are one or two lateral openings, or"eyes,"for the flow of urine. In the absence of a proper instrument various tubes may be improvised, e.g. an elder stem, a piece of lead piping about the diameter of the little finger, the long nozzle of a syringe to which a length of rubber tubing is attached, or any stiff rubber tube of suitable size. But it is not always necessary to pass the catheter in order to empty the bladder or to obtain a sample of urine. Not infrequently the mare and cow can be induced to urinate by merely introducing the finger into the urethra, or by gently rubbing and tickling the skin immediately below the vulva. The latter method is par ticularly successful in the cow, unless, perchance, the bladder is paralysed. It is scarcely neces sary to add that in females, as well as males, the precautions with regard to cleanliness and disinfection should be carefully observed on account of the danger of infecting the bladder and other parts of the urinary apparatus. When the animal, for example the cow, is down and unable to rise, much assistance is obtained by placing a bundle or two of straw under the hind quarters. Raising the hind parts throws the weight forward and reduces the pressure on the hand, and instrument. Lastly, the catheter may, if desired, be left in the bladder by tying narrow tape, or strong silk thread, to the rings at the end of the catheter, and fastening the thread or tape to a stitch in the vulva.
In the Cow the urethra is longer and much smaller than in the mare, and the somewhat valvular opening barely admits the tip of the forefinger. Just behind the opening there is a short blind pouch, or"cul-de-sac,"on the floor of the passage, which must be covered by the finger; otherwise the point of the catheter is certain to enter the pouch instead of the urethra. Raising the valve with the tip of the finger, the instrument is slipped alongside into the urethral opening. A slightly curved metal tube is generally preferred; if the point be cut off obliquely it is more easily introduced. The bent double-channelled human uterine tube, known as Fritsch's catheter, makes an excellent cow catheter. We have used this instrument for many years, and have found it easy to introduce, and very suitable for washing out the bladder.
The Bitch offers no special difficulty. The urethral opening is situated on the floor of the passage a short distance within the orifice. It is readily located with the tip of the fore finger. If necessary, a wire speculum may be employed to dilate the vulva and expose the opening. Any small sterile tube answers the purpose—for example, stiff rubber with a solid end and a lateral opening or"eye"—but preference is given to a short, curved, metal tube. The bitch may be operated upon stand ing, or stretched out on a table in an upright position with the limbs secured by means of tape hobbles.
The Sow and female Cat are catheterized in a similar manner.
In the female cat it is very difficult to find the mouth of the urethra. When found, how ever, the passage of the catheter presents no difficulty.
In dogs and cats it is often advisable in cases of distended bladder to puncture the bladder through the abdominal wall to afford immediate relief, as in some cases of considerable distension the struggling caused by the passage of the catheter may bring about rupture of the bladder with fatal results.
Retention of Urine. This is a condition in which urine accumulates in the paralysed bladder to an inordinate extent. Paralysis is the most common cause, as seen in 'fractures, loss of power in the hind parts, and in milk fever in cows. Yet any obstruction to the outflow of urine may give rise to retention. These impediments take the form of calculi (stones), impacted either in the urethral tube or in the neck of the bladder. Tumours and enlarged glands, like the prostate, may also press upon, and diminish the calibre of, the tube. Sometimes the obstruction affects the free portion of the penis at or near its extremity. In the horse accumulations of sebaceous material in the sheath may block the urethral orifice, while injuries which result in inability to extrude the penis, or to draw it back, may be a cause of retention in any animal.
Symptoms.All animals strain and make frequent attempts to pass urine, but as a rule they only succeed in passing a few drops, and show evidence of pain during the act. Horses and cattle whisk the tail, paddle with the hind feet, straddle the hind legs, and kick at the belly. Cats and dogs often assume a sitting position, and walk very stiffly with the back arched. In these and other small animals the over distended bladder may be detected by inserting the finger in the rectum and pressing on the lower part of the abdomen with the other hand.
The bladder feels quite firm, and extends far forward, resting on the floor of the abdomen. The frequent, painful, and more or less fruitless efforts at urination attract attention to the condition, and call for an early and careful examination on the part of the veterinary surgeon with a view to the discovery and removal of the cause. When the hand can be introduced into the rectum, as in horses and cattle, the swollen urinary bladder is at once recognized, and the patient shrinks or groans if pressure is exerted upon it. It is true that in certain forms of"colic,"especially those associated with obstruction to the passage of faeces, somewhat similar symptoms of retention may be shown; and the attendant, not un naturally, thinks that there is"something wrong with the water."But the easy passage of the catheter in such cases proves that no obstruc tion to the outflow of urine exists, while the emptying of the bladder affords no relief. Nor does the horse affected with colic make such frequent attempts to stale. Yet it must not be supposed that retention is always painful. In milk fever and other nervous affections accompanied by paralysis, the accumulation of urine in the bladder is not accompanied by pain, at least in the early stages. Nevertheless, when urine is allowed to collect for any length of time, the organ is liable to become inflamed, and even ruptured, and a peculiar form of blood-poisoning, the so-called"uraemia"or"urnaic poisoning,"may set in rapidly. When this occurs the whole body acquires a urinous odour; there is a high temperature; complete loss of appetite; the patient staggers and looks very miserable; he struggles and becomes unable to rise from loss of power in the hind limbs; and convulsions and stupor set in, followed by death within two or three days. Vomition is generally observed in the dog. Cattle appear to withstand the effects of com plete obstruction longer than other animals. Some of our cases have lived until the tenth day, while longer periods have been recorded.
Treatment is necessarily dependent on the cause. First-aid measures consist in giving frequent enemas of warm soapy water, and the application of hot fomentations to the loins, followed by a draught consisting of a pint of linseed oil and one ounce of laudanum for the horse and ox. Plenty of linseed tea should also be given. In these animals the attendant may, by emptying the rectum and pressing on the distended bladder in a careful manner, succeed in bringing about a flow of urine. Yet it is generally necessary, and always advisable, to pass the catheter when possible, both to locate the obstruction and to draw off the urine. While the operation presents no difficulty in paralytic conditions, the instrument may require to be used twice daily until nerve power is restored. The surgical treatment of stone in the bladder and urethra, and of inflammation of the bladder, will be considered later on.
Treatment. Calculi require surgical treat ment. If the blood is derived from the urethra the catheter should be used with caution in the male owing to the risk of injury. Never theless, the surgeon may require to douche the lower urinary passages with astringent solutions such as alum, sulphate of zinc, or adrenalin. Considerable haemorrhage calls for the adminis tration of drugs, such as ergot and acetate of lead, which tend to stop the flow of blood. Opium (laudanum) also assures to the animal rest and quietness which are essential to the arrest of haemorrhage, irrespective of its source. While the services of a veterinary surgeon should always be obtained, the patient should be made warm and comfortable, and given a dose of oil and laudanum, as recommended for retention, followed by a linseed mash, and drinks consisting of hay tea, linseed tea, oatmeal gruel, etc. Castor-oil, with a few drops of laudanum, and a milk diet are best for the dog and cat. Need less to say, any food or medicine which may have given rise to irritation should be discon tinued.
Urinary Calculi—Stones or Gravel in the Urinary Organs This condition may affect any animal, but most commonly the ox and sheep, followed closely by the dog. Less often calculi are seen in the horse. The influence of sex and age is of some importance. Although females are often affected, it is well known that stones are much more likely to become arrested in the narrower urinary passages of the male, e.g. the bull and ram; while advancing age favours their formation. The urine of all animals contains a varying percentage of salts in solu tion, the amount and chemical composition of which depend principally on the character of the food and drinking-water. Under ordinary conditions the salts are excreted with the urine; but in animals which are improperly fed, or which possess some special or hereditary pre disposition, it sometimes happens that the saline ingredients undergo precipitation—that is, they are thrown out of solution—and are deposited in the kidneys and bladder in the form of stone like masses or concretions, called calculi. The word"calculus"simply means a little stone. The salts, however, are not always formed into calculi. They may form a sandy or gritty deposit, which accumulates in the bladder and passes out with the urine. The gritty sediment, often called"gravel,"consists of particles of calcareous material which are, in reality, very small stones. When stones are lodged in the kidneys they are known as renal calculi; in the bladder, as cystic or vesical calculi; in the urethra, as urethral calculi. Although they may become arrested in the ureters during their passage from the kidneys to the bladder, they never originate in these tubes. Similarly, urethral calculi have their origin, as a rule, in the bladder, from whence they are forced into the urethra with the urine.
The formation of the stone, as may be imagined, is a gradual process. The salts, thrown out of solution or suspension in the urine, collect round some nucleus which happens to be present in the urinary passage. By the deposition of successive layers the small stone, or calcareous granule, slowly increases in circumference until the calculus in the kidney or bladder may attain the size of a duck's egg. In the horse, in these situations, they are generally few in number; indeed, only one large stone may be present, mainly composed of carbonate of lime with a certain proportion of phosphates. The calculi of oxen and sheep have the same chemical composition, but they are often small and numerous. In pigs and dogs phosphatic calculi are more common than other varieties. These salts, it should be remembered, are always present in the urine; but certain circumstances may arise in which they are deposited in one or more parts of the urinary apparatus.
The causes must be looked for in various directions. In the first place, the factors men tioned are undoubtedly of a predisposing or contributory nature, i.e. age, individual tend ency, and heredity. Females seldom suffer from obstruction on account of the short wide urethra, which permits small calculi to be easily passed. Secondly, the character of the food is a matter of importance; for feeding experiments show that variations in the quan tity and nature of the feeding-stuffs have a decided influence on the formation and chemical composition of the stones. Thus urinary calculi are more often met with in districts where the soil is of a chalky nature. On such land both the crops and the drinking-water are liable to contain excessive quantities of lime, and an increased percentage of lime salts in the blood and urine is the natural result. In the same way cattle and sheep fed on roots and fodder grown with large quantities of artificial manure frequently suffer, as well as animals on grass which has been heavily top-dressed with lime or basic slag. Possibly the relative amounts of drinking-water and succulent food have a direct bearing on the subject. Dry feeding is certainly a predisposing cause in ruminants. But de position of the salts of the urine is a phenomenon constantly occurring, apart from conditions of soil, from a too generous allowance of nitro genous food, particularly when accompanied by insufficient exercise, and the indigestion pro duced by over-feeding. This explains why sheep and lambs, young bulls and heifers, fattened on quantities of dry foods, such as cake, grains, and bran, are specially subject to calcareous deposits. Beets, maize, and other sugary and starchy foods, even turnips, have also been blamed; but the effect of too many turnips is, to say the least, doubtful, unless grown with excessive quantities of artificials.
Before leaving the subject of food as a causative factor about which many illogical opinions have been expressed, we would deprecate the common practice of blaming one particular article of diet. Often it is the system of management, or rather the regime, which is at fault, not a certain food. Again, cases of urinary calculi occur independently of the food as the result of in flammatory disease of the urinary organs (see"Inflammation of Kidneys and Bladder"). These diseases lead to pronounced chemical changes in the urine, whereby certain of the dissolved salts are precipitated and formed into stones or gravel. A fruitful cause, in this connection, is retention of urine, which acts in a similar manner.
As in all other diseases, an accurate diagnosis is essential. We should know whether stones are present at all; and, if so, where they are situated, and to what extent inflammatory changes have taken place. With the aid of the X-rays it is possible, in dogs and other small creatures, to detect the presence of stone in the kidney; but unless the accumulations reach the bladder, or are passed in the urine, an accurate diagnosis of renal calculi is fre quently a matter of great difficulty in horses and cattle. The occasional symptoms which are shown are often obscure, and ascribed to other causes. Why is an accurate diagnosis of urinary calculi so important ? It is obvious that early recognition is advantageous for purposes of prevention, which include a change of diet, an abundant supply of pure water, and regular exercise. Again, the patient, when seriously affected, may be promptly destroyed or slaughtered for human food, provided its value does not justify the performance of a surgical operation and the cost of a few weeks' keep. The fact that effective treatment can be adopted in suitable cases before inflammation sets in should also be borne in mind. These considera tions should weigh with the stock-owner in seek ing expert advice, as soon as the condition is suspected or discovered; or immediately any thing is noticed wrong with the"water." Urinary Calculi in the Horse. Stones in the kidney, or renal calculi, are comparatively seldom seen in the horse, although they may easily be overlooked. One or both kidneys may contain a single large stone or several smaller stones, without any symptoms being observed during life. It is interesting to note that the same phenomenon occurs in man. According to Rose and is an un doubted fact that stones even of large size may exist for years in the kidney without giving rise to any symptoms whatever."Some times the"stones"are present in the form of gravel, when small gritty granules may be found in the urine, or several small calculi may be come embedded in the substance of the kidney. But cases are met with in which one large calculus occupies the pelvis of the kidney. Large calculi are always irregular in shape, and assume the form of the cavity in which they lie. Like bladder calculi, they increase in size by gradual deposition of the salts of the urine, until the kidney may become largely absorbed, and little may remain but the capsule or outside covering. In other instances, the constant irri tation leads to inflammation of the kidney (see"Nephritis"). As a rule, some of the following symptoms are occasionally shown: colicky pains, especially after exercise or work; ten derness on pressure over the loins; stretching out and straining during repeated attempts to stale; blood in the urine after exertion; stiff ness of the loins and hind limbs when made to move; sandy or gritty deposits in the urine, and inflammatory products observed by the microscope; and, lastly, enlargement of the kidney and evidence of pain on introducing the hand far up the bowel. Stone in the kidney may be suspected when gravel and inflammatory products are present in the urine without anything being found wrong with the urethra and bladder. It should be remembered, how ever, that small stones may be washed into the narrow ureters at intervals, stopping the flow of urine, and causing severe colic; but the obstruction and pain are of a temporary nature. As a rule, small stones readily find their way into the bladder, where they may grow into large calculi.
Treatment is merely palliative, owing to the fact that operations on the horse's kidney are impracticable. Treatment should be carried out on the same lines as in congestion and inflammation of the kidneys, with plenty of fluids, a dessertspoonful of bicarbonate of soda in the drinking-water several times a day, and careful dieting. Chloral hydrate and Indian hemp relieve the pain when colicky symptoms are manifested.
Stone in the Bladder — Vesical Calculus (Horses). The bladder is the most common situation in the horse. Several small calculi may be found; or, more often, one large stone more or less egg-shaped, and rough or smooth 1 Manual of Surgery, eighth edition, 1911, p. 1196.
on the surface. In other cases a condition known as"sabulous bladder"is met with in which the calcareous material takes the form of sand or gravel. This deposit is distinctly gritty, and may be seen on the floor of the stable or in the sediment when the urine is collected and allowed to stand. The calculus may be formed in the bladder, or it may be derived from the kidney. Some stones attain the size of a man's fist. As in the kidney, a small stone may not cause much trouble, and its existence may remain unsuspected for years; but larger stones frequently give rise to a very irritable condition of the bladder, of which the almost constant efforts to stale is a prominent symptom. This symptom is more marked in bladder than in urethral calculi. Not uncom monly, inflammation of the bladder is set up, when the symptoms of that condition are observed (see"Cystitis"). The horse walks stiffly, stretches himself out, and may kick at his belly; he looks round to his side, and shows other signs of pain and discomfort. Frequent whisking of the tail is also noticed. Sometimes the urine is passed quite freely until the stone is forced into the neck of the bladder, when the flow is suddenly interrupted. In other instances the urine is continually dribbling away from the penis. Occasionally it is mixed with a little blood. A high colour of the urine with a strong ammoniacal odour is evidence that it has been retained in the bladder for some time. It is often observed that the above symptoms are brought on or aggravated by exercise or work. Sooner or later the general health suffers, and the horse loses condition and strength; he may become much emaciated. The diagnosis of stone in the bladder seldom offers much diffi culty. In the gelding and stallion all that is necessary is to empty the rectum and to intro duce the well-soaped hand. If the bladder is full, most of the urine should be drawn off with the catheter; when empty, the injection of a quart of fluid assists the detection of the calculus. With a metal catheter the operator may be able to recognize the characteristic metallic click caused by the end of the instru ment coming in contact with the hard stone. The sensation imparted by an accumulation of gravel in the bladder resembles that produced by the presence of wet sand in a bag. In the mare the fingers can be pushed into the organ quite easily through the short wide urethra; if the other hand is simultaneously introduced into the bowel, in order to draw the bladder back, the stone is pressed against the finger and readily extracted with forceps. Lastly, in both sexes, reliable evidence can often be obtained by examining the urine.
Stone in the Urethra — Urethral Calculus (Horse).Stones are never arrested in this situation in the mare; but it sometimes happens that small stones pass from the bladder into the long, curved, and comparatively narrow urethral canal of the male, and become impacted at various points. Often the stone is lodged close to the anus, and may be felt as a firm swelling in the middle line along the course of the tube. There may also be a fluctuating swelling above or beyond the stone from the urethra becoming dilated with urine. The passage of the catheter is arrested at this spot, and the metallic click is both heard and felt when a metal instrument, or one with a metal end, is employed. The symptoms, which appear suddenly, as a rule, depend on the amount of interference with the expulsion of urine. If the tube is completely blocked, it is evident that urination will be suspended, and the bladder will become very full and swollen. Unless re lieved, the animal's condition rapidly becomes grave, and death may follow from urine (urmic) poisoning or rupture (see"Retention of Urine"). Fortunately, the obstruction is often only partial, permitting small quantities of urine to be voided. The horse makes frequent pain ful attempts, but may be unable to pass more than a few drops at a time. Attention is drawn to the case by the pain, scanty urination, and the over-distended bladder on rectal examina tion. In exceptional instances small stones or gravel are found impacted near the extremity of the penis, which is seized and drawn out as in passing the catheter. An attempt is then made to press the stone towards the orifice of the urethra. Its extraction is assisted by the injection of a little warm olive-oil and the insertion of long, narrow forceps. Sometimes it is necessary for the surgeon to lay open the urethral orifice with the knife, although cutting should be avoided, if possible. Unless a rush of urine follows the removal of the stone, the catheter should be employed to locate other calculi which are probably situated farther up the tube. Collections of sebaceous material and dirt in the horse's sheath may also obstruct the orifice of the urethra; but this is easily remedied by washing out the prepuce with soap and warm water.
Treatment. Stones in the bladder and urethra usually require a surgical operation for their extraction; hence the owner is advised to consult his veterinary surgeon as soon as sus picious signs make their appearance. In the meantime, he might try copious warm enemas, and gentle pressure on the bladder through the bowel. We have known cases in which these simple measures were successful in moving the obstruction, and permitting a free discharge of urine. It is of course useless to attempt to dissolve the stone. This is a popular fallacy, and medicinal agents administered for this purpose are certain to fail in their object. If possible, the horse should be operated upon in the standing position, for casting entails the risk of rupturing the distended bladder. As a rule, a good sedative or narcotic dose is given, cocaine is injected over the site of operation, the twitch and blinders are applied, and the hind limbs are secured with hobbles similar to those employed for covering mares. Stocks furnish the best means of restraint when avail able. After bandaging and tying round the tail, the surgeon, with every antiseptic pre caution, proceeds to insert the catheter and to cut down upon it over the calculus, when the latter is lodged in the urethra. The incision is made exactly in the middle line in the direction of the tube. The stone is then pressed or scooped out, or extracted with forceps, its removal being followed by a rush of urine. The wound is often left unstitched, and merely cleansed and disinfected twice daily for a few days until urine ceases to trickle from it. During this time a little lard should be smeared over the thighs to prevent excoriation of the skin. Healing is generally complete within three weeks.
The operation for stone in the bladder is per formed in a somewhat similar manner, but the horse is sometimes carefully cast and chloro formed and the rectum is emptied. The passage of the catheter, or the injection of fluid, enables the operator to find the urethra and to open it without difficulty. It also enables him to remove the urine, and to cleanse and dis infect the bladder by the injection of one or two pints of a weak solution of boracic acid, thus moderately distending the organ and lessening the risk of injury from the forceps. The incision down on to the catheter is made close to the anus, and the opening is enlarged in the direction of the bladder as the catheter is partially withdrawn. With one hand in the rectum drawing the bladder back, the fingers of the other hand are introduced as far as possible into the urethra until the stone is felt and extracted with forceps. It may be neces sary to crush the stone before its removal can be effected. The operation is simplified by the fact that the distended bladder is close at hand; its neck, as well as the urethra, can also be very considerably dilated with the fingers and forceps. Needless to say, the hand in the rectum is of great assistance in guiding the forceps. It may happen that small calculi can be pressed back into the wound, thus dispensing with the use of instruments. Finally, the bladder is douched with a warm solution of boracic acid, and the wound is treated as before. In the mare, it will be remembered, the urethra opens on the floor of the passage about four inches from the outside, rendering the extraction of the calculus with forceps a simple matter. The knife is seldom required.
Urinary Calculi in the Ox.Stones in the kidney, although uncommon, are of more frequent occurrence in cattle than in horses. The symptoms and changes are very similar in both species, and further description is there fore unnecessary. As in the horse, no special symptoms of renal calculi may be observed, and their existence is frequently overlooked. The same remarks apply, in the main, to stone in the bladder, the symptoms of which may be more obscure than in the horse. Again, for the anatomical reasons already mentioned, urethral calculi only cause obstruction in the male, for the narrow, double-curved tube renders the passage of even small stones difficult or im possible. The bull is generally considered to suffer more than any other animal from urethral calculi, but the ram is also frequently affected. The stones, which are small and numerous, as a rule, are washed from the bladder into the long, small, curved canal called the urethra. They often become impacted, or arrested, in the bent portion of the canal a little behind the scrotum, occasionally near the anus, or the extremity of the penis. Sometimes the salts of the urine, instead of forming stones in the urethra, collect on the long hairs in front of the prepuce, where they crystallize out like sugar candy on a thread. Cases of this nature are quite familiar to stock-owners in certain dis tricts. The calcareous accumulation is gener ally white in colour, and tends to block the opening of the sheath, which becomes swollen and inflamed. The sheath soon acquires a strong urinous odour from decomposition of the retained urine. The condition is relieved by clipping the long hairs, opening up the prepuce, if necessary, with the knife, and syringing it repeatedly with a weak antiseptic solution. At the same time, a brisk purgative drench should be administered, e.g. one to one and a half pounds of Epsom or Glauber salts, with one pound of treacle, in two quarts of warm water. A change of food is also desirable. As in the horse, the symptoms of urethral calculi are due to interference with the expul sion of urine. The animal becomes uneasy, stamps and paddles with his hind feet, kicks at his belly, and whisks his tail. In severe cases, with complete obstruction, the flow of urine ceases altogether; but, as a rule, a few drops are passed at frequent intervals, with more or less straining and pain. Sometimes a little blood is noticed. While the distended bladder may be recognized by introducing the hand into the rectum, it may be impossible to feel the calculi on account of their small size and the fact that the urethra of the ox is more deeply situated than that of the horse. If the stone completely blocks the canal, the animal's condition rapidly becomes grave; the appetite fails, and the enormously swollen bladder may rupture within twenty-four hours unless relief is afforded. The skin acquires an odour of urine, and, although cattle may live for some time after rupture, there is only one termina tion.
Urinary Calculi in Pigs.Pigs are seldom affected. The causes (see"General Remarks on Urinary Calculi"), symptoms, and treatment do not differ from those described in other animals. Male pigs are more liable to suffer from the effects of gravel than females. Apart from the nature of the food, voluntary retention of urine is probably a common cause in fat pigs, which lie for hours in one position, and appear to be too lazy to rise and make their water. Should certain salts be present in excess in the blood and urine, they show a decided tendency to crystallize out and deposit whenever urine is retained in the bladder. The stones, or gravel, as in other animals, are chiefly arrested in the urethral canal, where they interfere with the passage of urine. Fat pigs should be promptly butchered, unless the deposits can be squeezed out or washed out with the catheter. But the urethral canal may be opened higher up, as described in the horse. Preventive measures include a reduction in the bran and meal ration, and an increased allowance of green stuffs, with quantities of milk, barley water, or linseed. The sharps may be discontinued for a time if no other cause can be discovered. Fat pigs should be forced to take exercise several times a day.
Urinary Calculi in the Dog and Cat.Stones in the kidneys, or renal calculi, are by no means common in the smaller species, although they are more often seen in the dog when the kidneys are examined after death. Old dogs are more frequently affected, not only in the kidneys, but in other parts of the urinary passages, as the bladder and urethra. In many cases no symptoms of renal calculi are manifested during life, or they are so obscure that it is impossible to make an accurate diagnosis. When, how ever, small stones, or calcareous particles, leave the kidneys, and cause obstruction lower down, more definite and serious symptoms arise. In the kidney, as elsewhere, calculi set up a chronic inflammation and irritation, with chemical changes in the urine, and sometimes a little blood, particularly after exertion and with the last portion of urine. The constant irritation leads to frequent urination in small quantities, or in drops, accompanied by straining, arching Of the back, disinclination to move, and stiffness of the loins and hind limbs. When these symp toms happen to be present, the urine should be collected, or drawn off with the catheter, and set up for some hours. Should a calcareous sediment form and nothing be found wrong with the urethra and bladder, an X-ray photograph may reveal the stone in the kidney. As a rule, the stone is large and irregular in shape.
Treatment is mainly directed to relieving pain, increasing the quantity of urine, and regulating the diet (see"Acute and Chronic Nephritis"). Urinary sedatives are sometimes useful, but most attention should be paid to regulating the bowels and exercise, and providing warm dry housing and a milk diet. A little bicarbonate of soda, or acetate of potash, may be given occasionally in the milk or barley water, and plenty of fresh drinking-water should be allowed. These measures will often enable the patient to live in comfort for years, with perhaps occasional relapses of pain. Operations on the kidney are seldom performed in the lower animals; but it is quite possible, as in man, to remove the stone under chloroform, provided the case warrants surgical interference and the difficulties of diagnosis can be overcome. The kidney is reached through an incision in the flank, when it is either cut open and stitched after extracting the stone, or the whole organ is carefully separated from its attachments and removed after ligaturing the blood-vessels.
Stones in the bladder, or vesical calculi, are often numerous, small, and approaching the spherical in shape; but one or two large calculi may be present. Although of more common occurrence in old dogs and cats, puppies and kittens are by no means exempt. As in large animals, it sometimes happens that the salts, which crystallize out from the urine, fail to form calculi and are deposited as gritty par ticles resembling fine gravel or sand. The symp toms resemble those already described; they depend to a great extent on the degree of obstruction to the outflow of urine and upon the inflammatory changes in the bladder (see"Cystitis"). The stones, now and then, cause little discomfort; but, in most cases, the animal becomes restless and uneasy, and strains fre quently, passing only a few drops of urine, which may be blood-stained, especially after exercise. When the stone is forced into the neck of the bladder, or into the urethra, the flow of urine may suddenly cease, and the dog shows distinct evidence of pain, becomes feverish, loses his appetite, and suffers in condition: Small, smooth calculi sometimes lie unsuspected in the bladder for a long time, or they may be passed occasionally in the urine, particularly in the form of gravel. With a metal catheter one may succeed in tapping the stone, while the finger in the rectum maintains contact with the distended bladder.
Treatment is necessarily surgical, and consists in the removal of the stone whole or in a broken-up condition. At the same time the general line of treatment laid down for cystitis should be observed. What might be termed the direct method of operation is often resorted to by the surgeon. It is both simple and satis factory. The male dog, or cat, is prepared, chloroformed, and laid upon its back, when the abdomen is opened on its lower surface in the middle line close to the edge of the bony pelvis, the penis being pushed to one side. The bladder is then drawn into the wound, incised to permit the extraction of the stone, and stitched so as to secure immediate union of the edges and prevent leakage. An alter native method is sometimes practised, in the same way as in the horse, by making an opening in the urethral tube below the anus. Which ever plan is adopted, the bladder is first emptied by means of the catheter, and washed out with a weak solution of boracic acid or other non irritating disinfectant. A little of this solution is allowed to remain in the bladder to facilitate the removal of the calculus. In the bitch the stone can be withdrawn through the urethra without the use of the knife. It may interest the reader to know that when it is desired to illuminate and observe the interior of the bladder a very neat and useful instrument, called a cystoscope, may be introduced like an ordinary catheter. Fitted with an electric lamp and an arrangement of mirrors, the cystoscope is in daily use in human surgery. An X-ray photo graph is often taken in the first instance.
Stones in the urethra, or urethral calculi, are quite frequently met with in the male dog. They are derived from the bladder, and pass along the urethra from time to time, with symptoms of pain and more or less obstruction to the expulsion of urine. Sometimes they become impacted in the tube and completely block it. Stones are thus often present in the bladder as well as in the urethra. Large cal culi, however, are unable to enter the narrower passage, and remain in the bladder. In the urethral tube the gravel (or stones) tends to become arrested in the narrowest parts, par ticularly in the bone of the penis, or immediately behind it. Often the calculi are small, numerous, and misshapen from contact with one another. In the male cat, on the other hand, stones are only occasionally seen. Most frequently the cat suffers from a collection of sandy or gravelly material at the extremity of the penis. It follows that the symptoms in these small animals appear suddenly, as a rule, and show a tendency to recur, especially in the case of the dog. The urine is voided with difficulty in drops, or in very small amounts, and there may be a little fluid or clotted blood mixed with the urine. Sometimes the patient suffers acute pain and makes almost constant efforts to urinate. According to the amount of obstruction, the urine retained in the bladder undergoes fer mentation, distends the organ, and gives rise to inflammation, urine poisoning, or even, in somewhat rare cases, to rupture of the bladder. Protrusion of the penis is a common symptom in the cat. As a rule, the condition is easily detected, and the calculus located, by intro ducing a metal catheter and making it strike against the hard object. The end of the instru ment, and the stone itself, may be felt under the skin. In some cases it is possible to feel the swollen condition of the urethra behind the calculus, while the swollen bladder can always be detected through the floor of the abdomen and by means of the finger in the rectum.
Treatment is generally operative; yet an attempt should be made with a small probe or catheter to dislodge the stone and enable it to be washed out with the urine. At the same time, gentle pressure should be exerted on the bladder. Manipulation of the end of the penis may succeed in pressing out the gravel which accumulates at this spot in the cat, and even in the dog. Urgent symptoms call for puncture of the bladder through the lower wall of the abdomen by means of a hollow needle, or a special instrument. By thus reducing the pres sure of the urine, small stones may be washed out with the next flow. But the operation of opening the urethra is often the only means of giving relief. It is performed in the same manner as in the horse. For the dog a dose of morphia, followed by an injection of cocaine, is safer than chloroform on account of the danger of rupture of the bladder. With the usual precautions (see"Passage of Catheter") the catheter is pushed forward until it meets with the obstruction, and the point can be felt under the skin. The tube of the urethra is then cut in a longitudinal direction, and the stones are removed with a probe, small forceps, or a small spoon. Next, with the aid of a syringe, the bladder and tube are flushed out with a mild disinfectant solution. The wound is frequently left unstitched, and, although a little urine escapes for a few days, healing generally takes place in about a fortnight if the wound is regularly washed and dressed.