Part 70

Diagnosis. From advanced or chronic peritonitis it is distinguished by the history or evidence of diseased liver, heart, or kidney, the absence of hyperthermia or abdominal tenderness, and the absence in the ascitic fluid, extracted with a hypodermic needle, of blood globules, or leucocytes in numbers, of false membranes, of excess of salts, or of a tendency to coagulate firmly.

From overdistended bladder it is diagnosed by its slow, and gradual development, and the change of fluctuation to the most dependent part no matter what position is given to the patient, whereas the tense bladder can be felt through the abdominal walls, extending forward from the pelvis under all circumstances.

From ruptured bladder there is the same distinguishing feature of slow development, the absence of symptoms of uræmic poisoning, of tenderness of the bladder, and of suppression of urine, and also of the urinous odor in the ascitic liquid obtained with the hypodermic needle.

From advanced gestation the differentiation is found in the general diffusion of the swelling and fluctuation, which is not confined as in gestation to the mobile uterine horns, with a series of enlargements each containing a solid nodular fœtus.

From hydrometra and pyometra there are the same pathognomonic differential features of the general diffusion of the swelling among the intestines, and its accumulation in one fluctuating mass at the most dependent part of the abdomen.

Tympany of the bowels causes uniform drumlike resonance, and the swelling does not sag and fluctuate in the lower part of the abdomen.

Abdominal obesity in old dogs gives the rounded swollen abdomen, but there is an entire absence of the pendulous and fluctuating features, and when punctured with the hypodermic needle it furnishes no fluid.

From tuberculosis it is distinguished by the absence of nasal discharge, or of tubercle bacilli in such discharge, or in the ascitic fluid, and the latter inoculated on guinea pigs or rabbits does not cause tuberculosis. The tuberculin test may also be resorted to.

Lesions. The liquid exudate has been found to amount to 30 or 40 quarts in large dogs (Hordt). It is often clear and translucent, of amber tint, though in some cases it is slightly opaque, or reddish yellow. It may remain fluid after extraction or again it may form a loose jelly. It may be red in case of soft tumors or other neoplasms. The liquid is very watery but may contain a considerable amount of fatty globules or granules, and a few epithelial cells and leucocytes. The peritoneum is pale or in advanced cases dull white from fatty degeneration of the epithelium.

Treatment. The first consideration is the removal of the cause. If this is a mere vicious action of the peritoneum, or the presence of a thrombus, or of operable tumor, or even of curable disease of the liver or kidneys, success may be hoped for, while in dilatation of the heart, insufficiency of the cardiac valves, irremediable disease of the lungs, liver or kidney, or malignant or inoperable tumor no such result can be hoped for.

Apart from the removal of the cause the first indication is to evacuate the liquid and this may be done with a large hypodermic needle or small cannula and trochar inserted by preference on or near the linea alba while the animal is in a standing position. Skin and instrument should be rendered thoroughly aseptic, and a bandage should be wrapped round the abdomen and gradually tightened as the liquid escapes. This to a large extent obviates the tendency to faint, or to cerebral anæmia which has caused sudden death in a number of cases. It also to some extent counteracts the sudden effusion of blood in the abdomen, which is at times determined by the sense of vacuity.

Injection of a solution of iodine (tincture of iodine 1 pt., iodide of potassium 1 pt., boiled water 20 pts.) has been employed sometimes with success, but in other cases it has roused a fatal inflammation. It is best adapted to a simple morbid, relaxed state of the peritoneum.

Saline purgatives (sulphate of soda or magnesia) are especially useful in constipated cases and should be pushed in continuous action, as far as the strength of the animal will warrant. By depletion from the portal system they oppose the tendency to mechanical transudation, while by rendering the portal blood more dense they strongly solicit endosmosis from the adjacent peritoneum.

Diuretics have been used extensively and with benefit. They may prove injurious in a kidney that is already the seat of irritation and yet after all be the least of two evils. In some cases instead, the resulting dilution of a dense and irritating urine is directly soothing to the tender kidney. Saltpeter (10 to 15 grs.), acetate of soda (15 to 30 grs.), squills (1 to 2 scr.), may be repeated so as to keep up a free action. Pilocarpine (subcutem) (¹⁄₁₀₆ to ¹⁄₃₀ gr. daily), has removed the ascitic fluid in 14 days (Zahn), but its action is always to be dreaded in a weak system, or with a diseased heart, or lungs.

A supporting bandage on the abdomen is always useful as counteracting the tendency to vacuity and further transudation.

A course of bitters and iron, and a supporting diet, and out door life (sunshine) are important elements in treatment.

DISEASES OF THE LIVER.

In veterinary and medical works the diseases of the liver have been accorded a minor place, ill in keeping with the great physiological importance of the organ. If the function of the liver were circumscribed by the mere secretion of bile there would be some excuse for the apparent neglect, as the gland is so deeply situated and so much enveloped in surrounding organs that physical exploration is difficult and somewhat unsatisfactory, and the one symptom of jaundice was long relied on as indicating hepatic disorder.

Taking into account all the varied functions of the liver we realize the wide-reaching nature of its physiological influence and the extensive and varied effect of its disorders. We can also deduce, with greater or lesser certainty, the existence of hepatic disorders from the morbid conditions of the blood or of organs, the functions of which are inter-dependent with those of the liver. To elucidate the subject it is well to trace some of the most prominent functions of the liver; the following considerations are submitted.

SANGUIFICATION IN THE LIVER.

Glycogenic function. Glycogen derived through glucose and laevulose from starch, glycerine, milk and cane sugars. Less from proteids. Peptones as a source. Its use in cell growth and heat production, in white blood cells, in contracting muscle, becoming lactic acid. Excess dissolves red globules, setting free hæmoglobin. Ammonia carbonate and asparagin increases it. Arsenic, phosphorus or antimony arrests glycogenesis. Liver increases leucocytes, and reduces size of red globules. Reduction of proteids. Fibrine formers reduced, urea formed; liver inactivity means less of soluble urea, and more of less soluble and more dangerous products. Urea increases with hepatic circulation. Hepatic disorder and suppression of urine dangerous. Red globules probably destroyed. Bile: Amount, uses, oil solvent, helps endosmosis, deodorant, stimulates glycogenesis, excretory. Source of bile pigments, tests. Bile acids, dissolve blood globules, antiseptic, tests. Bile increased by; bile absorbed from bowel, olive oil, salol, salicylates, benzoic acid and benzoates, turpentine, terpene, terpinol, euonymus, alkalies, arsenic, ether. Agents lessening biliary secretion, starvation, excess of fat, alkaline iodides, atropia, strychnia, hepatic diseases, septic duodenal fermentation. Arrest in liver of copper, iron, iodides, bromides, nicotine, quinine, morphia, curare, toxic bile products, ptomaines, toxins. Reduces toxicity of peptones, casein, ammonia salts, indol, phenol.

The liver is the goal to which most of the products of gastric and intestinal digestion are carried by the portal vein. In the hepatic cells large quantities of glycogen, 6 (C{6}H{10}O{5}) + H{2}O, are stored up after each meal. This is believed to be derived largely from the transformation of glucose, (C{6}H{12}O{6}) and laevulose (C{6}H{12}O{6}) which have been produced from starch in the alimentary canal and conveyed by the portal vein to the liver. By the liberal use of starch, glycerine, or the sugars of milk, fruit or cane, (but not mannite, or glycol, or inosite) the glycogen is very greatly increased (to 12 per cent. in the fowl), but it is diminished on a purely albuminous diet. Yet it can be produced from albuminous food, as it is always increased in the dog after a meal of flesh, and is largely present in the livers of carnivorous animals that have been fed for a month on flesh only (Landois). The peptones are therefore decomposed in the liver with the production of glycogen and such waste products as leucin and tyrosin, which are finally resolved into urea. A purely fatty diet diminishes it enormously and during prolonged abstinence it practically disappears. It passes, not into the bile, but into the hepatic veins, and the general circulation, where it serves in its decomposition to generate heat, and probably to hasten cell growth. In the vegetable and animal world, in the germinating seed, and in cartilage, muscle and epidermis of the fœtus and in the amnios, glycogen and glucose are found in abundance. The liver, too, the great center for the production of glycogen, is relatively much larger in the young and growing animal, and also in the adult animal which has great power of assimilation.

Glycogen is always present in the white blood globules so long as they maintain their vitality and amœboid movements, but when they die, it is replaced by sugar (Hoppe-Seyler). The red blood globules give up a ferment which rapidly transforms glycogen into sugar.

Glycogen and sugar are evidently of use in muscular contraction as they are always diminished in the vessels of contracting muscles (Sanderson), being converted into lactic acid (Bernard).

Forced muscular movements soon expel glycogen from the dog’s liver, passing it into the blood, and there the excess of glycogen dissolves the red blood globules. If glycogen is injected into the blood, achrodextrin and hæmaglobin appear in the urine (Landois).

Ammonia carbonate and asparagin, or glycin, with a carbhydrate diet produced in rabbits a considerable increase of glycogen (Rohmann).

Poisoning by arsenic, phosphorus or antimony destroys the glycogenic function of the liver, which then fails to respond even to diabetic puncture of the medulla.

There are important changes effected in the blood globules in passing through the liver. The leucocytes are increased, the hepatic veins containing 5 or even 10 times as many as the portal vein (Bernard, Lehmann, McDonald). Their ratio to the red globules is in the portal vein 1:524 and in the hepatic veins 1:136 (Hirt). The red globules undergo marked changes, having, in the hepatic veins, a smaller size, sharper outlines, less flattening in the disc, a habit of massing together irregularly in place of adhering in rouleaux, and they dissolve less readily in water.