Inflammation of the pericardium (heart bag) is often a.s.sociated with pneumonia and pleurisy, rheumatism, and other const.i.tutional diseases, or with an injury. It also occurs as an independent affection, owing to causes similar to those of other chest affections, as exposure to cold or dampness and changes of the weather.
_Symptoms._--It may be ushered in with a chill, followed by fever, of more or less severity; the animal stands still and dull, with head hanging low, and anxiety expressed in its countenance. The pulse may be large, perhaps hard; there is also a venous pulse. The hand against the chest will feel the beating of the heart, which is often irregular, sometimes violent, and in other instances weak, depending in part upon the quant.i.ty of fluid that has transuded into the pericardial sac. The legs are cold, the breathing quickened and usually abdominal; if the left side of the chest is pressed on or struck, the animal evinces pain. There may be spasms of the muscles in the region of the breast, neck, or hind legs. After a variable time swelling may also appear in the legs and under the chest and brisket.
In those animals in which the heart sounds may be heard somewhat distinctly, the ear applied against the chest will detect a to-and-fro friction sound, corresponding to the beats of the heart. This sound is produced by the rubbing of the internal surface of the heart bag against the external surface of the heart. During the first stages of the inflammation these surfaces are dry, and the rubbing of one against the other during the contraction and relaxation of the heart produces this sound. The dry stage is followed by the exudation of fluid into the heart sac, and the friction is not heard until the fluid is absorbed sufficiently to allow the surfaces to come in contact again. But during the time the friction sound is lost a sound which has been called a "churning noise" may take its place.
The friction sound of pericarditis can not be mistaken for the friction sound of pleurisy if the examination is a careful one, because in the heart affection the sound is made in connection with the heart beats, while in the pleuritic affection the sound is synchronous with each respiration or breath of air taken in and expelled from the lungs.
_Treatment._--When pericarditis is complicated with rheumatism or other diseases the latter must be treated as directed in the description of them.
The animal must be kept in a quiet, comfortable place, where it will be free from excitement. Warm clothing should be applied to the body, and the legs should be hand-rubbed until the circulation in them is reestablished, and then they should be snugly bandaged. The food should be nutritive and in moderate quant.i.ty. Bleeding should not be performed unless the case is in the hands of an expert.
At the beginning give as a purgative Epsom salt--1 pound to an average-sized cow--dissolved in about a quart of warm water and administered as a drench. When there is much pain 2 ounces of laudanum, diluted with a pint of water, may be given every three hours until the animal is better. Do not give the laudanum unless demanded by the severity of the pain, as it tends to constipate. Give one-half ounce of nitrate of pota.s.sium (saltpeter), dissolved in drinking water, four or five times a day. After the attack has abated mustard mixed with water may be rubbed well over the left side of the chest to stimulate the absorption of the fluid within the pericardium. The other medicines may be discontinued and the following administered: Sulphate of iron, 2 ounces; powdered gentian, 6 ounces; mix and make 8 powders. Give one powder every day at noon, mixed with feed, if the animal will eat it, or shaken up with water in a bottle as a drench. Also the following: Iodid of pota.s.sium, 2 ounces; nitrate of pota.s.sium, 8 ounces; mix and make 16 powders. Give one in drinking water or in drench every morning and evening. The last two prescriptions may be continued for several weeks if necessary.
In extreme cases tapping the pericardium with a trocar and cannula to draw off the fluid is resorted to, but the operation requires exact anatomical knowledge.
After death from pericarditis there is always more or less fluid found in the pericardium; the surfaces are rough and covered with a yellow-colored exudate. There are also in many cases adhesions to a greater or less extent between the heart and pericardium.
MYOCARDITIS.
Inflammation of the muscular structure of the heart occurs in limited, circ.u.mscribed areas, as evidenced by post-mortem examination, and it is probably always somewhat involved in connection with pericarditis and endocarditis. It may readily be inferred that if the whole organ were inflamed death would ensue immediately. Usually myocarditis results from the preexistence of blood poisoning or of some infectious febrile disease.
_Symptoms._--The chief symptoms are those of heart weakness. The heart beat is fast, weak, and often irregular. Respiration is difficult and rapid.
There is great general weakness and depression. Death comes suddenly.
_Treatment._--Treatment consists in supporting the animal by the use of stimulants, such as ammonia, coffee, digitalis, camphor, etc. Complete quiet must be provided, and the general care should be as in pericarditis.
ENDOCARDITIS.
When the membrane which lines the cavities of the heart--the endocardium-- suffers inflammation, the disease is called endocarditis. The cause is another disease, during which substances that irritate the lining of the heart are produced and admitted into the circulation. These substances are usually living organisms, or it is possible that in some cases they are chemical irritants. Endocarditis occurs as a complication of or sequel to pneumonia, blood poisoning, inflammation of the womb, rheumatism, or severe wounds or abscesses. The symptoms are much the same as those of pericarditis, and it is difficult to discriminate between the two affections. There is a jugular pulse, the legs may become dropsical, and there is a tendency to faint if the head is elevated suddenly. The bellowslike sound is more distinct than it is in pericarditis. It is the most fatal of heart diseases, because of the liability of the formation of clots, which may adhere to the valves, change in the structure of the valves, and often a complication with an abnormal condition of the blood.
Clots may be formed in the heart, and, being carried to other parts, prove fatal by interrupting the circulation in some vital organ.
Treatment similar to that advised for myocarditis may be followed in this disease.
VALVES OF THE HEART.
The valves are subject to abnormal growths and structural changes in chronic endocarditis or as a result of acute endocarditis. Sometimes valves are torn by sudden, extreme muscular effort or a congenital abnormality.
Cases are also reported in which they have been found ruptured.
_Symptoms._--The general symptoms are those of heart weakness, accompanied with edema and congestion of the lungs.
_Treatment._--Relief is sometimes afforded, but usually only temporarily, by the use of stimulants, especially digitalis.
RUPTURE OF THE HEART.
Sudden effort, blows, or disease may lead to rupture of the heart of the ox. The first cause does not operate so often in cattle as in horses.
Tuberculosis or ulceration from other causes, such as a foreign body, is the most common source of this accident. Rupture is shown by sudden fainting, followed very shortly by death.
HYPERTROPHY AND DILATATION OF THE HEART.
This is an enlargement of the heart, and may consist of the thickening of the walls alone, or at the same time the cavities may be either enlarged or diminished. Dilatation of the cavities has been noticed as existing independently of thickened walls. In hypertrophy the sounds of the heart are loud and p.r.o.nounced, may be heard on both sides of the chest distinctly, and palpitation occurs to a greater or less extent. Fortunately both conditions are very rare in cattle.
ATROPHY.
Atrophy is the technical term for wasting of the muscular tissue. Atrophy of the heart is very rare among cattle, and is usually a result of other diseases.
FATTY DEGENERATION OF THE HEART.
This condition of the heart is met with in some very fat cattle, but it must be understood that the acc.u.mulation of fat around the heart is not referred to by this designation. In fatty degeneration the elements of the muscular tissue are replaced by fatty or oily granules. The muscle becomes weak, the heart contractions are insufficient, and heart weakness is shown by general weakness, shortness of breath, and weak, rapid pulse.
CYANOSIS.
Owing to the most prominent symptoms, cyanosis is also called "blue disease," and is seen occasionally in new-born calves. It is recognized by the blue color of the mucous membrane (easily seen by looking within the mouth and nostrils), the coldness of the surface of the body, and rapid, labored breathing. It is caused by non-closure of the foramen ovale, connecting the right with the left side of the heart, and the consequent mixing of the venous with the arterial blood. Calves so affected live but a short time.
MISPLACEMENT OF THE HEART.
Cases are recorded in which the heart has been found out of its natural position, sometimes even outside the chest. This is a congenital condition for which there is no remedy. A heifer calf with the heart entirely outside the thoracic cavity and beneath the skin in the lower part of the neck was kept for two years at the veterinary hospital of the University of Pennsylvania, during which time it grew to be a well-developed cow.
WOUNDS OF ARTERIES AND VEINS.
When a blood vessel is opened a glance will tell whether it is an artery or a vein by simply remembering that bright-red blood comes from arteries and dark-red from veins. When a vein or a very small artery is severed the blood flows from the vessel in a continuous and even stream, but when one of the larger arteries is severed the blood comes in intermitting jets or spurts corresponding to the beats of the heart. It is well to call attention to the fact that the dark-red blood which flows or oozes from a wound soon becomes bright red, because it gives up its carbonic-acid gas to the air, and absorbs oxygen gas from the air, which is exactly the change it undergoes in the capillaries of the lungs.
The general treatment of wounds will be found in another section; here it is necessary only to refer briefly to some of the most practical methods used to arrest hemorrhages, as instances occur in which an animal may lose much strength from the loss of blood, or even bleed to death unless action is prompt.
BLEEDING (HEMORRHAGE).
The severity of a hemorrhage depends upon the size of the vessel from which the blood escapes, though it may be stated that it is more serious when arteries are severed. If the wound in an artery is in the direction of its length, the blood escapes more freely than if the vessel is completely severed, because in the latter instance the severed ends retract, curl in, and may aid very much in arresting the flow. When the blood merely oozes from the wound, and even when it flows in a small stream, the forming of the clot arrests the hemorrhage in a comparatively short time.
Slight hemorrhages may be checked by the continuous application of cold water, ice, or snow, to the wound, as cold causes contraction of the small vessels. Water from a hose may be thrown on a wound, or dashed on it from the hand or a cup, or folds of cotton cloths may be held on it and kept wet. Ice or snow may be held against the wound, or they may be put into a bag and conveniently secured in position.
Hot water of an average temperature of 115 to 120 F. injected into the v.a.g.i.n.a or womb is often efficient in arresting hemorrhages from those organs. Tow, raw cotton, lint, or sponges may be forced into a wound and held or bound there with bandages. This is an excellent method of checking the flow of blood until the arrival of an expert. If the flow persists, these articles may be saturated with tincture of iron, but it is not advisable to use it unless necessary, as it is a caustic and r.e.t.a.r.ds healing by causing a slough. In cases of necessity, the articles may be saturated with vinegar, or tannic acid or alum dissolved in water may be used instead. Whatever article is used should be left in the wound sufficiently long to make sure that its removal will not be followed by a renewal of the hemorrhage. Sometimes it must remain there one or two days.
An iron heated white and then pressed on the bleeding vessel for three or four seconds is occasionally used. It should not be applied longer, or else the charred tissue will come away with the iron and thus defeat the purpose of its application.
Compression may be applied in different ways, but only the most convenient will be mentioned. To many wounds bandages may easily be applied. The bandages may be made of linen, muslin, etc., sufficiently wide and long, according to the nature of the wound and the region to be bandaged. Bed sheets torn in strips the full length make excellent bandages for this purpose. Cotton batting, tow, or a piece of sponge may be placed on the wound and firmly bound there with the bandages.
Many cases require ligating, which is almost entirely confined to arteries.
A ligature is a piece of thread or string tied around the vessel. Veins are not ligated unless very large (and even then only when other means are not available) on account of the danger of causing phlebitis, or inflammation of a vein. The ligature is tied around the end of the artery, but in some instances this is difficult and it is necessary to include some of the adjacent tissue, although care should be taken not to include a nerve. To apply a ligature, it is necessary to have artery forceps (tweezers or small pincers may suffice) by which to draw out the artery in order to tie the string around it. To grasp the vessel it may be necessary to sponge the blood from the wound so that the end will be exposed. In case the end of the bleeding artery has retracted, a sharp-pointed hook, called a tenaculum, is used to draw it out far enough to tie. The ligature should be drawn tightly, so that the middle and internal coats will be cut through.
Another method of checking hemorrhage is called torsion. It consists in catching the end of the bleeding vessel, drawing it out a little, and then twisting it around a few times with the forceps, which lacerates the internal coats so that a check is effected. This is very effectual in small vessels, and is to be preferred to ligatures, because it leaves no foreign body in the wound. A needle or pin may be stuck through the edges of the wound and a string pa.s.sed around between the free ends and the skin (Pl.