HERNIA, in its widest sense, signifies a protrusion, through an abnormal or acciden tal opening, of any organ from its natural cavity. Although hernia may occur in many parts of the body, the word, used by itself, is restricted to signify protrusion of the abdominal viscera.
The way in which hernia may arise will be readily understood, if we bear in mind that the abdominal viscera are subject to violent pressure from the diaphragm and other surrounding muscles. This pressure forces them outwards and downwards against the walls of the belly; and if at any point these walls are not sufficiently strong to resist this pressure, some portion of the viscera is driven through them, and a hernial tutnor is formed. Certain parts of the abdominal walls, especially the inguinal and crural rings, and the umbilicus, being weaker than others, hernia most frequently occurs at these points. In some instances hernia is congenital, as from abnormal deficiency of the walls; in other cases, it may arise at any period of life as a result of violent bodily exertion. Sex, age, and occupation seem to have a marked influence in predisposing to hernia. Men are far more liable (in about the proportion of four to one) to this dis ease than women; though they are less so to those forms of the affection known as femoral and umbilical hernia. According to Malgaigne, in France, one man in thirteen, and one woman in fifty-two, are the subjects of hernia. In respect of age, he found that the liability is least about the age of 13 (1 in 77), after which it progressively increases until the close of life, rising at 70-75 to 1 in 3.
A hernia is almost always composed of a sac and its contents. The sac is a portion of the peritoneum (q.v.) corresponding to the aperture at which the hernia protrudes. It is pushed forivard 'by time protruding viscera, and fottistt pouch. The contents vary greatly, but generally consist of a portion of the small intestine (particularly of the ileum), forming the variety of hernia known as enterocele. Omentum is often found in hernial sacs, together with intestine. Besides the viscera, the sac always contains a certain quantity of fluid secreted by its interior. Hernia is divisible (1) into reducibk, or returnable into the abdomen, irreducible, and and (2) according to its situation, into inguinal, crural, etc.
The treatment of reducible hernia may be palliative or radical. The palliative treat ment consists in the application of a truss (q.v.) to retain the protrusion within the cav ity of the abdomen. Each particular kind of hernia (femoral, crural, etc.) requires its special form of truss; and before applying it, the hernia must be reduced by placing the patient on his back, relaxing the muscles by bending the thigh upon the abdomen, and pressing the tumor back in the proper direction. The truss should then be put on, and
should he worn during the whole of the day; and if the patient will submit to wear it (or a lighter one) during the night, so much the better. The means that have been con trived to effect a radical cure are too purely surgical for description in these paces. Below the age of puberty, and if the hernia is recent, a radical cure is sometimes effected by wearing the truss for two or three years.
In irreducible hernia the protruded viscera cannot be returned into the abdomen, but there is no impediment to the passage of their contents or to their circulation. In these cases, the patient is often liable to dragging pains in the abdomen, and to attacks of vomiting, in consequence of the movements of the stomach being checked by the omentum or the intestines being fixed. There is also constant danger of this hernia passing into the strangulated form. The treatment may be either palliative or radical. The palliative treatment consists in the employment of a truss with a hollow pad that shall embrace the hernia and prevent any additional protrusion. A radical cure may sometimes be obtained by keeping the patient in the recumbent position, and on very low diet for two or three months; at the same time keeping the bowels open by laxatives and injections, and maintaining equable pressure over the tumor.
Hernia is said to be strangtflated when a portion of intestine or omentum that is protruded is so tightly constricted that it not only cannot be returned into the abdomen, hut has its circulation arrested. This form is highly dangerous, because, if relief is not speedily afforded, the strangulated part becomes gangrenous. The causes of strangula tion are various, but this condition most commonly arises from is sudden violent effort, by which a fresh portion of intestine is driven into a pre-existing hernia, which it dis tends to such a degree as to produce this complication. The most prominent early symptoms are flatulence, colicky pains, etc. They are succeeded by vomiting first of the contents of the stomach, then of mucus and bile, and lastly of fecal matters, owing to inverted peristaltic action. If relief is not obtained, the inflammation that com mences in the sac extends to the peritoneum, and the ordinary signs of peritonitis appear. After a variable time comes gangrene or mortification of the part, and the uatient speedily sinks.
The surgeon first tries to return the intestine, as in the preceding cases. This manip ulation, termed the taxis, may be assisted by the internal use of chloroform, inhaled till it. produces complete relaxation of the muscle, by general to the verge of faint ness, by the hot bath, etc. If this fails, he must have recourse to the knife to divide the constriction.