LARYNX Traumatic Lesions. Open Wounds. Open wounds of the pharynx in the horse may be caused by a sharp-pointed stick used to administer a ball, or by dental instruments incautiously employed or accidentally slipping from the teeth and coming in contact with the pharyngeal walls. A foreign body lodged in the pharynx may wound its lining or perforate its structure, and gain exit through the skin by provoking an abscess which bursts externally. Rarely, the pharynx is wounded from without inwards.
Symptoms. Haemorrhage may occur through the mouth or nose and symptoms of pharyngitis supervene, characterized by difficulty in swal lowing, alimentary matter being returned by the nostrils, and by salivation.
Septicaemia or pyinia may ensue from virulent infection of the wound. A fistula may be present as the result of perforation of the pharyngeal wall.
Treatment. Treatment is that for pharyn gitis, and little can be done except to prescribe semi-liquid demulcent diet and antiseptic and astringent electuary containing borax or potassium chlorate, which may be associated with an anodyne like the green extract of belladonna.
A recent fistula with clean-cut edges may be sutured through the skin, and one of long standing must be cauterized or freshened and closed with a purse-string suture.
Foreign Bodies.A foreign body may be lodged in the pharynx of any animal, but most commonly in that of the dog and cat, in which the object may be a piece of wood or bone, a pin, a needle, or a fish-hook.
In the horse and ox the foreign body may also be a piece of wood, a needle, a bit of wire, a hair-pin, or part of a root or tuber, etc. A portion of potato or root may lodge in the pharyngeal pouch of the pig.
Symptoms. The symptoms are those of choking or more or less obstruction of the entrance to the cesophagus, and comprise coughing, dysphagia, or inability to swallow, salivation, evidence of distress or discomfort revealed by an anxious expression and by uneasiness, and attempts at vomiting in the dog and cat.
In the small animals the offending object can be readily detected by opening the mouth widely and depressing the base of the tongue.
In the larger species it may be felt by the hand. In the ox it can be reached in any part of the pharynx, but in the horse it cannot be manipulated if it is further back than the level of the epiglottis.
Treatment. Extract the foreign body by means of the hand or forceps or a hook. The hand alone is usually sufficient in the ox, but in the horse it may fail to reach the object, and a forceps or hook may then answer the purpose. An artery forceps is convenient for use in the small animals. In all cases the patient's jaws should be kept separated by a speculum. When a sharp-pointed body, such as a needle or pin, is left in situ, it eventually finds its way out through the medium of an abscess, bursting in the region of the throat.
Parasites.Cases are recorded as occurring in Spain and Northern Africa of blood-sucking parasites taken in in the drinking-water becom ing fixed on the mucous membrane of the pharynx and larynx. The engorged parasites may burst, causing the escape of blood from the nose. They may give rise to anaemia and debility. Affecting the larynx they cause a varying degree of dyspncea which may amount almost to asphyxia.
The larvae of the (Estrus equi have also been found in these situations, producing similar symptoms.
Treatment. It has been recommended to put eels in the drinking ponds, as they devour the parasites. Suspected water should be filtered before being given to animals to drink. Fumi gation by pitch or tobacco seldom has much effect on the pests, which are best removed directly by means of a piece of stick whose end is furnished with a sponge or pad impreg nated with ether. They may also be taken off by the aid of forceps, or the hand alone when within reach.
Tumours.Actinomycotic tumours are com mon in the pharynx of the ox. Apart from these, pharyngeal neoplasms are comparatively rare in veterinary practice. Fibromata, sarcomata, and epitheliomata are occasionally met with.
Symptoms. — The symptoms are those of chronic pharyngitis with more or less pro nounced dysphagia. Dyspncea and a respira tory noise may supervene from encroachment of the tumour on the air passage. A pedun culated growth often becomes displaced by the act of swallowing, especially during feeding, when it may obstruct the entrance to the cesophagus and give rise to a fit of coughing which ejects the food material through the mouth and nose. If the pedicle is long the tumour may fall into the lumen of the larynx and produce sudden dyspncea, which is relieved by the animal coughing and expelling the obstruction. Rarely, death supervenes from asphyxia owing to the patient being unable to dislodge the obstacle in this way.
If the enlargement involves the posterior nares it causes snoring and a variable amount of dyspncea, according to its size, especially during feeding; or rumination in the ox. When an attack of severe dyspncea occurs due to sudden obstruction of the larynx by a polypus, the animal becomes greatly distressed and appears to be fighting for breath, pawing the ground, heaving at the flanks, and evincing an anxious expression with dilated nostril. When the tumour is coughed out of the passage the patient becomes normal again.
In the dog and cat vomiting is sometimes induced by the presence of the tumour in the fauces.
Diagnosis. Diagnosis may be confirmed by external examination of the pharyngeal region, where a large tumour can be felt by manip ulation when the head is extended, or by exploration through the mouth, which is easy in the ox and small animals but difficult in the horse on account of the length of the soft palate and of the jaws, or through the larynx after performing laryngotomy, or through the nose by the aid of a sound passed in through the nostrils. The rhino-laryngoscope would prove very useful in cases where diagnosis is diffi cult.
Prognosis. Generally speaking, the prognosis is grave. Sessile tumours, whether malignant or benign, are inoperable. Pedunculated growths can generally be removed.
Actinomycotic swellings respond to internal medication. Malignant growths are incurable.
Treatment. Inoperable actinomycotic tum ours can be treated successfully by the internal administration of potassium iodide or biniodide of mercury. (See"Actinomycosis.") Pedunculated growths may be removed by one of the following methods: 1. Through, the Mouth. If there is danger of asphyxia during the operation, perform pro visional tracheotomy and insert a tube. Have the animal rigidly held or secured in stocks, and the mouth kept open with a speculum.
If there be difficulty in operating in the standing position cast the patient, making use of the ecraseur, pass the loop of chain round the pellicle of the tumour and sever it by slowly turning the handle. The growth might also be grasped by a long forceps and removed by torsion.
2. Through the larynx, after performing laryngotomy, not practicable as a rule.
3. Through an external wound in the pharyn geal wall made either at the level of the middle line of the larynx and hyoid bone, the pharynx being entered just in front of the epiglottis, or just beneath the wing of the atlas, parallel to the jugular vein, the cavity being reached by blunt dissection of the tissues in the angle of bifurcation of the carotid into its terminal branches, and by puncturing the mucous mem brane with a knife. This method is not likely to prove practical or beneficial.
It may be said that if operation by the mouth is not possible the case is hopeless.
Examination of the Larynx. The larynx can be examined externally by observation and palpation in the large and small animals. By keeping the head extended the organ becomes more prominent and more easily explored. Internally the larynx can be felt by the hand in the ox but not in the horse, where a point further back than the base of the epiglottis cannot be reached.
In the dog and cat the larynx can be easily seen when the mouth is well opened and the base of the tongue is depressed with a spatula, and it can be satisfactorily illuminated by the aid of a mirror and artificial light. For the horse the rhino-laryngoscope affords a clear and definite image of the larynx.
Traumatic Lesions. Contusions. The larynx may be affected by a contusion which seldom presents characters differing from those of this lesion elsewhere.
Sudden cessation of respiration and syncope have been known to follow a severe blow in flicted at the level of the larynx and upper part of the trachea in front of the neck. The symptoms and treatment of the condition are those of contusions in general.
Symptoms. When the lesion is produced externally the symptoms are the ordinary ones of an open wound, and in addition there may be emphysema of the tissues due to the cutan eous wound and that in the larynx not being confluent, and profuse bleeding into the larynx which may lead to asphyxia. When the trauma is confined to the interior of the organ there may be bleeding from the mouth and nose, and symptoms of laryngitis with more or less dyspncea will supervene. Asphyxia may ensue from severe laryngeal haemorrhage or oedema, and bronchopneumonia is a possible complication.
Treatment. The treatment is on general prin ciples. If the deep and superficial parts of the wound do not communicate freely causing emphysema, make them confluent by the use of the knife.
If asphyxia is threatened from haemorrhage into the trachea, perform tracheotomy and insert a tampon cannula, that is, a tube in one piece with a cylindrical bent stem which fits into the trachea and is enveloped in gauze to prevent the passage of blood into the lungs.
Even a clean incised wound penetrating the larynx, like that made in laryngotomy, is better left open, as suturing favours oedema and pre vents the escape of inflammatory discharge.
When the cartilage is not damaged, healing without complications takes place, but if one of the cartilages is wounded excessive granula tions are likely to form in the affected part, resulting in fibrous thickening or ossification of the larynx with diminution or almost oblitera tion of its lumen and consequent dyspncea, and asphyxia if relief is not afforded by the performance of tracheotomy.
There is usually a very foetid odour from the wound extending into the larynx. It is insignificant.
Internal wounds of the larynx can only be treated as laryngitis. If they cause dangerous dyspncea, tracheotomy will be necessary. Anti septic inhalations are indicated.
Fractures of the Larynx.The larynx is very rarely fractured.
The lesion is due to external violence, such as a kick or a horn-thrust, and causes dyspncea from the inflammatory swelling which ensues.
Bleeding may occur from the mouth and nose owing to laceration of the laryngeal mucous membrane. Tracheotomy is usually necessary to prevent asphyxia.
Foreign Bodies in the Larynx.There are many cases on record of foreign bodies in the larynx. In all cases of dysphagia there is a tendency for food material or medicine being partaken of or administered passing into the larynx, for example, in a case of sore throat, milk fever, or tetanus.
In dogs playing with objects in the mouth these are apt to fall into the pharynx and be accidentally aspirated into the larynx. Be sides ordinary alimentary matter and drugs, other solid bodies may become lodged in the laryngeal orifice, such as a needle, a pin, or a piece of wire, etc.
Symptoms. When foreign matter enters the larynx it excites coughing, which often serves to expel it. Should it fail to do so, dyspncea, varying in degree according to the amount of obstruction, supervenes. Repeated ineffectual coughing may occur, and difficulty in swallow ing may also be noticed should the patient attempt it.
Asphyxia is caused when the lumen of the organ is entirely occluded.
Diagnosis. Diagnosis may be difficult.
The condition may be confounded with obstruction in the pharynx or oesophagus. Passage of the cesophageal tube or probang will show that the gullet is clear.
In the ox, manual examination may reveal the nature of the case. In the small animals the object may be seen when the mouth is widely opened and the base of the tongue depressed with a spatula.
Treatment. Remove the foreign body by means of a forceps or hook introduced through the mouth, which is kept open by a speculum.
This method is not practicable in the horse, in which laryngotomy will be necessary to gain access to the interior of the larynx.