Читать книгу Special Report on Diseases of the Horse - Charles B. Michener - Страница 83

The larynx is situated in the space between the lower jawbones just back of the root of the tongue. It may be considered as a box (somewhat depressed on each side), composed principally of cartilages and small muscles, and lined on the inside with a continuation of the respiratory mucous membrane. Posteriorly it opens into and is continuous with the windpipe. It is the organ of the voice, the vocal cords being situated within it; but in the horse this function is of little consequence. It dilates and contracts to a certain extent, thus regulating the volume of air passing through it. The mucous membrane lining it internally is so highly sensitive that if the smallest particle of feed happens to drop into it from the pharynx violent coughing ensues instantly and is continued until the source of irritation is ejected. This is a provision of nature to prevent foreign substances gaining access to the lungs. That projection called Adam's apple in the neck of man is the prominent part of one of the cartilages forming the larynx.

Inflammation of the larynx is a serious and sometimes fatal disease, and, as before stated, is usually complicated with inflammation of the pharynx, constituting what is popularly known as "sore throat." The chief causes are chilling and exposure.

Symptoms.—About the first symptom noticed is cough, followed by difficulty in swallowing, which may be due to soreness of the membrane of the pharynx, over which the feed or water must pass, or from the pain caused by the contraction of the muscles necessary to impel the feed or water onward to the gullet; or this same contraction of the muscles may cause a pressure on the larynx and produce pain. In many instances the difficulty in swallowing is so great that water, and in some cases feed, is returned through the nose. This, however, does not occur in laryngitis alone, but only when the pharynx is involved in the inflammation. The glands between the lower jawbones and below the ears may be swollen. Pressure on the larynx induces coughing. The head is more or less "poked out," and has the appearance of being stiffly carried. The membrane in the nose becomes red. A discharge from the nostrils soon appears. As the disease advances, the breathing may assume a more or less noisy character; sometimes a harsh, rasping snore is emitted with every respiration, the breathing becomes hurried, and occasionally the animal seems threatened with suffocation.

Treatment.—In all cases steam the nostrils, as has been advised for cold in the head. In bad cases cause the steam to be inhaled continuously for hours—until relief is afforded. Have a bucketful of fresh boiling water every fifteen or twenty minutes. In each bucketful of water put a tablespoonful of oil of turpentine, or compound tincture of benzoin, the vapor of which will be carried along with the steam to the affected parts and have a beneficial effect. In mild cases steaming the nostrils five, six, or seven times a day will suffice.

The animal should be placed in a comfortable, dry stall (a box stall preferred), and should have pure air to breathe. The body should be blanketed, and bandages applied to the legs. The diet should consist of soft feed—bran mashes, scalded oats, linseed gruel, and, best of all, fresh grass, if in season. The manger, or trough, should neither be too high nor too low, but a temporary one should be constructed at about the height he carries his head. Having to reach too high or too low may cause so much pain that the animal would rather forego satisfying what little appetite he may have than inflict pain by craning his head for feed or water. A supply of fresh water should be before him all the time; he will not drink too much, nor will the cold water hurt him. Constipation (if present) must be relieved by enemas of warm water, administered three or four times during the twenty-four hours.

A liniment composed of 2 ounces of olive oil and 1 each of solution of ammonia and tincture of cantharides, well shaken together, may be thoroughly rubbed in about the throat from ear to ear, and about 6 inches down over the windpipe, and in the space between the lower jaws. This liniment should be applied once a day for two or three days.

If the animal is breathing with great difficulty, persevere in steaming the nostrils, and dissolve 2 drams of chlorate of potassium in every gallon of water he will drink; even if he can not swallow much of it, and even if it is returned through the nostrils, it will be of some benefit to the pharynx as a gargle.

An electuary of acetate of potash, 2 drams, honey, and licorice powder may be spread on the teeth with a paddle every few hours. If the pain of coughing is great, 2 or 3 grains of morphin may be added to the electuary.

When the breathing begins to be loud, relief is afforded in some cases by giving a drench composed of 2 drams of fluid extract of jaborandi in half a pint of water. If benefit is derived, this drench may be repeated four or five hours after the first dose is given. It will cause a free flow of saliva from the mouth.

In urgent cases, when suffocation seems inevitable, the operation of tracheotomy must be performed. To describe this operation in words that would make it comprehensible to the general reader is a more difficult task than performing the operation, which, in the hands of the expert, is simple and attended with little danger.

The operator should be provided with a tracheotomy tube (to be purchased from any veterinary instrument maker) and a sharp knife, a sponge, and a bucket of clean cold water. The place to be selected for opening the windpipe is that part which is found, upon examination, to be least covered with muscles, about 5 or 6 inches below the throat. Right here, then, is the place to cut through. Have an assistant hold the animal's head still. Grasp your knife firmly in the right hand, select the spot and make the cut from above to below directly on the median line on the anterior surface of the windpipe. Make the cut about 2 inches long in the windpipe; this necessitates cutting three or four rings. One bold stroke is usually sufficient, but if it is necessary to make several other cuts to finish the operation, do not hesitate. Your purpose is to make a hole in the windpipe sufficiently large to admit the tracheotomy tube. It is quickly manifested when the windpipe is severed; the hot air rushes out, and when air is taken in it is sucked in with a noise. A slight hemorrhage may result (it never amounts to much), which is easily controlled by washing the wound with a sponge and cold water, but use care not to get any water in the windpipe. Do not neglect to instruct your assistant to hold the head down immediately after the operation, so that the neck will be in a horizontal line. This will prevent the blood from getting into the windpipe and will allow it to drop directly on the ground. If you have the self-adjustable tube, it retains its place in the wound without further trouble after it is inserted. The other kind requires to be secured in position by means of two tapes or strings tied around the neck. After the hemorrhage is somewhat abated, sponge the blood away and see that the tube is thoroughly clean, then insert it, directing the tube downward toward the lungs.

The immediate relief this operation affords is gratifying to behold. The animal, a few minutes before on the verge of death from suffocation, emitting a loud wheezing sound with every breath, with haggard countenance, body swaying, pawing, gasping, fighting for breath, now breathes tranquilly, and may be in search of something to eat.

The tube should be removed once a day and cleaned with carbolic-acid solution (1 to 20), and the discharge washed away from the wound with a solution of carbolic acid, 1 part to 40 parts water. Several times a day the hand should be held over the opening in the tube to test the animal's ability to breathe through the nostrils, and as soon as it is demonstrated that breathing can be performed in the natural way the tube should be removed, the wound thoroughly cleansed with carbolic-acid solution (1 to 40), and closed by inserting four or five stitches through the skin and muscle. Do not include the cartilages of the windpipe in the stitches. Apply the solution to the wound three or four times a day until healed. When the tube is removed to clean it the lips of the wound may be pressed together to ascertain whether or not the horse can breathe through the larynx. The use of the tube should be discontinued as soon as possible.

It is true that tracheotomy tubes are seldom to be found on farms, and especially when most urgently required. In such instances there is nothing left to be done but, with a strong needle, pass a waxed end or other strong string through each side of the wound, including the cartilage of the windpipe, and keep the wound open by tying the strings over the neck.

During the time the tube is used the other treatment advised must not be neglected. After a few days the discharge from the nostrils becomes thicker and more profuse. This is a good symptom and signifies that the acute stage has passed. At any time during the attack, if the horse becomes weak, give whisky or aromatic spirits of ammonia, 2 ounces in water. Do not be in a hurry to put the animal back to work, but give plenty of time for a complete recovery. Gentle and gradually increasing exercise may be given as soon as the horse is able to stand it. The feed should be carefully selected and of good quality. Tonics, as iron or arsenic, may be employed.

If abscesses form in connection with the disease they must be opened to allow the escape of pus, but do not rashly plunge a knife into swollen glands; wait until you are certain the swelling contains pus. The formation of pus may be encouraged by the constant application of poultices for hours at a time. The best poultice for the purpose is made of linseed meal, with sufficient hot water to make a thick paste. If the glands remain swollen for some time after the attack, rub well over them an application of the following: Biniodid of mercury, 1 dram; lard, 1 ounce; mix well. This may be applied once every day until the part is blistered.

Sore throat is also a symptom of other diseases, such as influenza, strangles, purpura hemorrhagica, etc., which diseases may be consulted under their proper headings.

After a severe attack of inflammation of the larynx the mucous membrane may be left in a thickened condition, or an ulceration of the part may ensue, either of which is liable to produce a chronic cough. For the ulceration it is useless to prescribe, because it can neither be diagnosed nor topically treated by the nonprofessional.

If a chronic cough remains after all the other symptoms have disappeared, it is advisable to give 1 dram of iodid of potassium dissolved in a bucketful of drinking water, one hour before feeding, three times a day for a month if necessary. Also rub in well the preparation of iodid of mercury (as advised for the swollen glands) about the throat, from ear to ear, and in the space between the lower jawbones. The application may be repeated every third day until the part is blistered.