Part 64

Prognosis. The worst cases are promptly fatal, while others destroy life in one or two days and such are always to be recognized by the extreme dyspnœa which appears soon after the accident. The slight cases with small orifice and little protrusion may merge into the chronic form, and the animal may even be fit for work, notwithstanding existing dyspnœa, which closely resembles that of chronic emphysema (heaves), but is not benefited by the same treatment. In the ruminants even considerable lacerations and protrusions may not be incompatible with fattening provided the animal is kept from all causes of excitement or over-exertion.

Treatment. Surgical treatment has not proved successful. Expectant and medicinal treatment are the only available resorts and then only in the slighter cases. Quiet and the absence of all excitement is the first consideration to allow of an arrest of any increase of the hernia and the establishing of a healing process in the torn margins. Bouley strongly advises bleeding to allay abdominal pain. Chloral hydrate (1 ounce for the larger animals) will often meet the same end, with the additional advantage that it counteracts fermentation and tympany. The unloading of stomach and bowels by a cathartic, and the use of flaxseed meal or other concentrated food of a laxative nature are indicated. Small animals may be lifted by their fore limbs, and the abdomen may be meanwhile manipulated to favor the return of the hernial mass by gravitation. Large animals should be placed in a stall having an inclination downward and backward for the same reason. When it can be ascertained that the hernia consists of a loop of small intestine only, it is permissible, especially in cattle, carnivora and omnivora, to make an incision in the flank and with the disinfected hand to attempt the reduction of the hernia and the placing of a bulky viscus, like the rumen, stomach or liver in the way of its return. In case of violent abdominal pain Bouley advises active counter-irritation over the abdomen, but as strangulation is usually present in such cases, this measure may be held to be inferior in value to gravitation, anodynes, antiseptics, unloading of the gastro-intestinal organs and absolute rest or surgical interference.

DIAPHRAGMATIC HERNIA OF THE RETICULUM.

Anatomical reasons. Gullet, weight of stomach, riding, dystokia. Symptoms. Tendency to chronicity. Treatment.

In ruminants this is the most common phrenic hernia of a hollow abdominal viscus. On the right side the gastric and intestinal organs are separated from the diaphragm by the flat mass of the liver. A laceration in this region must therefore be extensive to allow of the protrusion of any abdominal organ into the chest. The left half of the diaphragm, however, comes in direct contact with the reticulum and any opening large enough to admit of this viscus is likely to entail hernia of the second stomach. The lesion is further favored by the fact that the gullet passes through this part of the diaphragm and is connected with the stomachs in the furrow between the first and second stomachs. In case, therefore, that the gullet is violently dragged upon by the weight of the contents of the overloaded or tympanitic paunch, or when the animal rises on its hind limbs, in riding its fellow, the foramen sinistrum is liable to be enlarged by laceration, and the second stomach most naturally protrudes through the opening. The strain thrown on the diaphragm in violent abdominal contraction, as in difficult parturition, is mainly expended on this left half, and the laceration takes place around the œsophagus, or as in cases reported by Schurinck and Siedamgrotzky through the aponeurotic portion. The protrusion may be composed of the second stomach alone, or together with portion of the paunch as observed by Schmidt in a goat, or of the third and fourth stomachs as in a case in a bull reported by Baraillé. The edges of the orifice may show, in recent cases, the fringed or irregular jagged outline with blood clots and thickening, or in chronic cases the pale, fibrous, smooth, even outline already described under diaphragmatic hernia.

The symptoms are like those of other forms of phrenic hernia, in ratio with its extent. The tendency to survival, and chronicity is greater than in the monogastric animals, 1st because the entrance of the smaller viscera is barred by the great gastric masses applied against the wound, and 2nd by the quiet uneventful life of the ox and the absence of active work and violent excitement.

Treatment will not differ from that of other forms of phrenic hernia.

HERNIA THROUGH THE MESENTERY, OMENTUM OR OTHER FOLD OF PERITONEUM.

Definition. Causes: Concussions in horse especially, anatomical conditions in cattle, pediculated tumors, dystokia, hernia of small intestine in horse, ox, broad ligament, pelvic hernia. Lesions: Congestion, hemorrhage of hernial viscus, adhesions, softening, thickening, strangulation. Symptoms: Intestinal obstruction, rectal exploration. Treatment: Laparotomy.

Definition. This consists in a protrusion through an opening, congenital or acquired, in the double fold of peritoneum (mesentery) which passes off from the abdominal wall to support a viscus, or that which passes from organ to organ (omentum).

Causes. The lacerations of mesentery or omentum are attributed to sudden concussions of various kinds (falls, blows, leaps, violent efforts), and have been especially found in horses in which the bulk and weight of the contents of the digestive organs furnish a special predisposition. In ruminants in which the contents of the abdomen are equally bulky and heavy the lesion is rarely seen, probably because the great bulk of the ingesta lies in the first three stomachs, and because the large intestines are folded up in the mesentery which supports the small, thereby strengthening this means of support and restricting the freedom of movement on the part of the intestines themselves. In carnivora the limited bulk of the intestines and their contents, and the relative shortness of the mesenteric folds largely obviate the predisposition.

Pediculated tumors of mesentery or omentum may drag on the delicate membrane so as to cause laceration, and circumscribed peritonitis, by producing softening and friability, may act as a causative factor. Violent straining in defecation or parturition is another cause of laceration.

In solipeds the loosely suspended and eminently mobile small intestine is the viscus which most commonly forms a hernia through such adventitious openings, either through the great mesentery, the great omentum, the gastro-splenic omentum, the mesentery of the umbilical vein (falciform ligament of the liver), or the gastro-hepatic omentum. Cases are on record, however, in which the floating colon, the double colon and even the cæcum formed herniæ through the peritoneal lacerations.

In cattle the most common lesion is the hernia of a knuckle of intestine through a laceration in the mesentery, but, the rupture has also occurred in the great omentum and exceptionally in the broad ligament of the uterus which is very extensive in these animals. Pelvic hernia or gut tie as usually described is dependent on a laceration of the mesentery of the spermatic artery.

Lesions. The fold of intestine which makes the hernia is liable to become strangled, and sometimes twisted in the opening, so that the circulation of blood and ingesta is interrupted, congestions and hemorrhages set in, and necrosis and general infection follow. Oftentimes a fibrinous exudate is thrown out, binding together the intestinal convolutions, and attaching them to the margins of the mesenteric or omental opening. Similarly the lips of the lacerated wound in the mesentery become covered with blood clots, or congested, or infiltrated, and sometimes the seat of extensive extravasations. The inflamed membrane may soften, become friable and tear more extensively, or if the patient survives, the exudation becomes organized, thickening and strengthening the margins of the wound and causing them to contract so as to strangle the enclosed loop of intestine.

Symptoms. The indications are those of intestinal obstruction, to which accordingly the reader is referred. The only possible indication of the exact nature of the lesion is to be obtained by rectal exploration. Herniæ through the meso-colon or broad uterine ligament may be reached in this way, and possibly diagnosed.

Treatment. Laparotomy alone gives any hope of success, and this will only be warranted when a certain diagnosis has been reached.

HERNIA THROUGH THE FORAMEN OF WINSLOW IN THE HORSE.

Anatomical considerations, small size and elevated position of foramen, length and freedom of mesentery of jejunum; spare diet, draught, straining, rolling, colic. Symptoms: of intestinal obstruction only, lesion found at necropsy.

The foramen of Winslow is a comparatively small opening between the lesser curvature of the stomach and the liver, and between the gullet and its cardiac ligament on the left side and the gastro-hepatic omentum on the left. With its elevated and anterior position in the abdomen it would seem to be little exposed to this kind of accident, yet a number of recorded instances in the horse, show that it is certainly not immune. The great mobility of the jejunum, owing to the extra length of its mesentery is believed to be the essential predisposing cause. A spare diet, or one which is in small bulk, allows the comparatively empty gut to pass more readily through the small opening. Severe efforts in draught and straining in defecation and parturition are also invoked as means of pressing the jejunum through the orifice. So with the concussions attendant on falls and the unwonted positions taken in decubitus and rolling on the back in wantonness or colic.

Symptoms of this lesion are essentially those of intestinal obstruction, with usually a rapid and fatal course. An accurate diagnosis is impossible during life.

OTHER FORMS OF HERNIA.

The other forms of hernia (umbilical, inguinal, scrotal, femoral, ventral, vaginal, ischiatic) are essentially surgical and need not be further referred to here, than to guard the reader against overlooking them as factors in producing intestinal and omental strangulation and colic. They are all to be recognized by the presence of a local swelling, which may often be obliterated by returning its contents into the abdominal cavity, which sensibly enlarges when the animal is made to cough, and which, if made up of intestine, is subject to gaseous distension, and gurgles when manipulated and returned. A violent colic occurring in a male animal should never be considered as certainly diagnosticated until the scrotal and inguinal region have been carefully examined for hernia.

PARALYSIS OF THE RECTUM.

In solipeds, ruminants, swine, carnivora. Injuries to loins and croup. Palsy of tail and sphincters. Nerve centres in end of cord. Fractures and dislocations of the pelvis. Hæmoglobinuria. Advanced gestation. Sclerosis. Ovariotomy by vagina. Impaction of rectum. Neoplasms. Thrombosis of internal iliac artery. Ptomaines and toxins in fevers. Symptoms: tardy defecation, impaction, over distension, fæces firm, dry, roller like, liquid oozing, excoriation, foul tail and thighs, bulging of anus, incontinence of urine. Paresis and wasting of quarter. Treatment: remove cause, for sprains and fractures sling, treat myelitis, debility, poisoning, unload rectum often, oily or soapy enemata, strychnia, eserine, ergot, barium chloride, derivations.

This is much more common in the horse than in ruminants, swine or carnivora, mainly because the soliped is more exposed to traumatic injuries of the loins, croup, and pelvic bones. It is noticeable that in the majority of cases the paralysis of the rectum is connected with palsy of the tail, anus, and sphincter vesicæ. This comes from the anatomical fact that the centres presiding over the motions of these different parts are situated close to each other in the terminal portion of the spinal cord, and any lesion of that part by traumatism or disease is likely to affect all of these parts alike.

The condition has been especially noticed in fractures or severe sprains of the loins causing pressure on the spinal cord. In some cases injury to the nerves supplied by this part of the cord, leads to an extension of inflammation to the nerve centres, thus paralysis of the rectum has followed on fracture of the ischium, dislocation of the sacro-iliac joint, or even of the first bone of the coccyx. Again, congestions and effusions on the terminal part of the cord, which occur in certain cases of hæmoglobinuria and in old hard worked horses is a cause of these local paralyses. Advanced gestation appears at times to produce the disease through pressure on the nerves, though it has also been noticed in non-breeding animals, and is doubtless traceable to sclerosis or other degenerations of the cord. It sometimes follows vaginal ovariotomy.

Sometimes the condition is traceable to local lesions as over distension of the rectum in horse or dog or in rectitis, but the result in such cases is usually partial, a paresis rather than a paralysis. The same may at times result from the growth of the neoplasms, and from the debility of old age. In other cases thrombosis of the aorta or internal iliac artery, implicates the hemorrhoidal vessels and paresis occurs as a result of the limited blood supply.