TUMORS OF THE KIDNEY (HYPERTROPHY OR ATROPHY).
The kidney may be the seat of cancerous or simple tumors, and it may be unnaturally enlarged or reduced in size, but though there may be signs of urinary disorder the true nature of the disease is seldom manifest until after death. The passing of blood and of large multi-nucleated cells in the urine (to be detected under the microscope) may betray the existence of an ulcerated cancer of the kidney. The presence of cancerous enlargement of (superficial) lymphatic glands may further assist and confirm the decision.
RETENTION OF URINE.
Inability to pass urine may come from any one of three conditions—first, spasm of the neck of the bladder; second, paralysis of the body of the bladder; third, obstruction of the channel of outlet by a stone (calculus) (see [Pl. XI]) or other obstacle.
In spasm of the neck of the bladder the male animal may stand with the tail slightly raised and making rhythmical contractions of the muscle beneath the anus (accelerator urinæ) (see [Pl. IX], fig. 2), but without passing a drop of liquid. In the female the hind legs are extended, widely parted, and the back is arched as if to urinate, but the effort is vain. If the oiled hand is introduced into the rectum or vagina in the early stages of the affection, the bladder may be felt beneath partially filled, but not overdistended with liquid, and its neck or mouth firm and rigid. In the more advanced stages of the affection the organ is felt as a great, tense, elastic bag, extending forward into the abdomen. In this condition the overdistended muscular coat of the bladder has lost its power of contraction, so that true paralysis has set in, the muscle closing the mouth of the sac alone retaining its contractile power.
In paralysis of the body of the bladder attention is rarely drawn to the urinary disorder until the bladder has been distended to full repletion and is almost ready to give way by rupture and to allow the escape of the contained liquid into the abdomen. Overdistention is the most common cause of the paralysis, yet it may occur from inflammation of the muscular wall of the bladder, or even from injury to the terminal part of the spinal marrow. In this last condition, however, the tail is liable to be powerless, and the neck of the bladder may also be paralyzed, so that the urine dribbles away continuously.
Causes.—Among the causes of spasm of the neck of the bladder may be named the lodgment of small stones or gravel, the feeding on irritant diuretics (see "Bloody urine," [p. 119], or "Nephritis," [p. 123]), the enforced retention of urine while at work or during a painful or difficult parturition. The irritation attendant on inflammation of the mucous membrane of the bladder may be a further cause of spasms of the neck, as may also be inflammation of the channel (urethra) back of the neck. Extensive applications of Spanish flies to the skin, the abuse of diuretics, and the occurrence of indigestion and spasms of the bowels are further causes. So long as spasmodic colic is unrelieved, retention of water from spasm of the neck of the bladder usually persists.
Treatment.—Treatment depends largely on the cause. In indigestion the irritant contents of the bowels must be got rid of by laxatives and injections of warm water; Spanish-fly blisters must be washed from the surface; a prolonged and too active exertion must be intermitted. The spasm may be relaxed by injecting one-half ounce of solid extract of belladonna in water into the rectum or by a solution of tobacco. Chloroform or ether may be given by inhalation, or chloral hydrate (1 ounce) may be given in water by the mouth. Fomentations of warm water may be made over the loins and between the thighs, and the oiled hand inserted into the rectum may press moderately on the anterior part of the bladder, which can be felt as an elastic fluctuating bag of an oval shape just beneath.
All other measures failing, the liquid must be drawn off through a tube (catheter). This is, however, exceedingly difficult, alike in male and female, and we can not expect an amateur to succeed in accomplishing it. In the cow the opening into the bladder is found in the median line of the floor of the generative entrance, about 4 inches in front of the external opening, but it is flanked on either side by a blind pouch, into which the catheter will pass, in ninety-nine cases out of a hundred, in the hands of any but the most skilled operator. In the bull or steer the penis, when retracted into its sheath, is bent upon itself like the letter S, just above the scrotum and testicles (see [Pl. IX], fig. 2), and unless this bend is effaced by extending the organ forward out of its sheath it is quite impossible to pass a catheter beyond this point. When, however, by the presentation of a female, the animal can be tempted to protrude the penis, so that it can be seized and extended, or when it can be manipulated forward out of the sheath, it becomes possible to pass a catheter of small caliber (one-third inch or under) onward into the bladder. Youatt advised laying open the sheath so as to reach and extend the penis, and others have advocated opening the urethra in the space between the thighs or just beneath the anus, but such formidable operations are beyond the stock owner. The incision of the narrow urethra through the great thickness of muscular and erectile bleeding tissue just beneath the anus is especially an operation of extreme delicacy and difficulty. Drawing the liquid through the tube of an aspirator is another possible resort for the professional man. The delicate needle of the aspirator is inserted in such cases through the floor of the vagina and upper wall of the bladder in the female, or through the floor of the rectum (last gut) and roof of the bladder in the male, or finally through the lower and back part of the abdominal wall, just in front of the bones of the pelvis (pubic bones), thence through the lower and anterior part of the bladder near its blind anterior end. After relief has been obtained the administration of belladonna in 2-dram doses daily for several days will tend to prevent a recurrence of the retention.
When the body of the bladder has become benumbed or paralyzed by overdistention, we may seek to restore its tone by doses of one-half a dram of powdered nux vomica repeated daily, and by mustard plaster applied over the loins, on the back part of the belly inferiorly, or between the thighs. Small doses (2 drams) of balsam of copaiba are sometimes useful in imparting tone to the partly paralyzed organ.