CHAPTER II.. Pathological Conditions.

PATHOLOGICAL CONDITIONS.

Section I. OF THE PERITONEUM.

This membrane we find liable to congestion, inflammation, gangrene, effusions, and morbid growths.

=Congestion= of the peritoneum, may result from obstructed circulation through the liver, or ascending vena cava, or from inflammatory action; and may terminate in serous effusions into the abdominal cavity, or thickening of the membrane. The redness of congestion, may be distinguished from that of inflammation, by the larger vessels appearing more involved, and by the absence of any plastic effusions.

=Inflammation= of this membrane, (Peritonitis,) may be either acute or chronic.

Acute peritonitis, in most instances, commences at some one or more points, and from this gradually diffuses itself over the membrane until it becomes general. Such point of inflammation may commence immediately over some inflamed, or ulcerated, or perforated spot in the intestines, or in the peritoneal covering of an inflamed uterus, liver, etc., or as the result of external injury.

In the early stage of peritonitis, the injected vessels give the membrane a more or less red appearance, which will be more marked in streaks and patches. From the readiness, however, with which fibrinous exudation takes place from this membrane, this redness is seldom very strongly marked, and in some instances will scarcely be noticed, unless the surface is carefully scraped, thus removing the exudation.

Small extravasations of blood are occasionally found in the substance of the membrane. The muscular coat of the intestines, where the peritoneal covering is involved, may become infiltrated with serum, the fibres relaxed and paralyzed, thus permitting of the great tympanitic distension found in these cases.

Chronic peritonitis, is not a very common occurrence. It may, however, follow an attack of acute peritonitis, and is sometimes found in connection with ascites, or tubercular deposits in the peritoneum. In examining the body of a colored woman who had died of heart disease, accompanied with general dropsy, and who had suffered abdominal pain and tenderness for a number of weeks previous to death, a large portion of the peritoneum, particularly that reflected upon the abdominal walls, was found intensely red, the blood-vessels having an arborescent arrangement, and being beautifully injected. No plastic matter was found effused upon the surfaces. The cavity contained some twelve quarts of serum.

=Fibrinous Exudation=, as already observed, readily follows inflammation of this membrane. It will often be found as a uniform layer covering the whole surface of the peritoneum, rendered more apparent, however, by separating parts, when it appears as delicate bands or filaments, stretching across the interspace. In cases of acute inflammation, this plastic effusion is often very great, and frequently intermixed with purulent matter, while the serous fluid, which is poured out in considerable quantities in these cases, is rendered turbid by the presence of numerous flakes of fibrin, and quantities of pus cells diffused through the same. More or less extensive and firm adhesion of parts may thus be induced, the plastic matter effused becoming more and more firm, and finally converted into dense bands of fibrous tissue.

Mechanical obstruction and strangulation of the bowels, may be induced by the presence of these bands, stretching between parts, and forming thus an opening through which the bowel passes, and finally becomes incarcerated.

=Suppuration= is not an unfrequent result of acute peritonitis; the matter being found uniformly smeared over the whole surface, or, in some cases, confined to a single part, thus forming a circumscribed abscess. Adhesions having taken place around the boundaries of the suppurating surfaces, in this manner the diffusion of the matter is prevented, and its discharge into the intestinal canal, or in some instances upon the surface of the body, is promoted.

=Gangrene= of the peritoneum may result from intussusception or hernial incarceration of some portion of the bowel, when the part will appear as a softened, dark, offensive mass, limited by a band of highly congested tissue.

=Ascites.= Dropsical accumulations in the abdominal cavity, may result from obstructed circulation, caused by disease of the liver, kidneys, heart or lungs; or from pressure upon the vena cava, or portal vein, by some abnormal growth.

The fluid effused may be nearly colorless, or present various shades of yellow, red or green, and usually coagulates on the application of heat. The peritoneum may appear unchanged, or it may present a thickened, opaque, white or macerated appearance, in chronic cases.

Blood may be found in the peritoneal cavity, as a result of wounds, rupture of some of the abdominal or pelvic organs, or bursting of an aneurism.

=Morbid Growths.=

=Tubercular Deposits=, of the miliary form, are not unfrequent in the peritoneum. They may be diffused over the whole membrane, as semi-transparent, gray granules, but more frequently are found on the under surface of the diaphragm, in the neighborhood of the spleen, and on the viscera generally, while the parietal layer is more free. The tubercles, acting as foreign bodies, give rise to inflammation, usually of a chronic form, but sufficient to result in exudation of lymph, and the formation of adhesions between the adjoining surfaces. Softening of the tubercular deposits sometimes takes place, and perforation of the intestinal wall results, leading to an effusion of the intestinal contents into the peritoneal cavity.

=Cancer= of the peritoneum, is sometimes seen as a primary affection, yet it more frequently extends to this membrane from some of the deeper parts. The encephaloid variety may be met with, but the colloid form is that most frequently seen. The omentum is the occasional seat of this form of cancer, the membrane in such cases becoming enormously increased in size.

=Tumors= of various kinds, including fibrous, fatty, and cystic, may be found in the peritoneal cavity, generally having had their origin, however, in the sub-peritoneal tissues. Fatty tumors may originate within the substance of the omentum or mesentery, while cystic tumors may be found within the broad ligaments of the uterus or ovaries.