HERNIA. 
268 
the back, portions of the bowel may come in contact with the lower 
part of the abdominal wall. Large dogs, if quiet, may be operated on 
standing. Either side may be chosen, provided one keeps close to the 
middle line, The posterior portion of the abdomen is usually preferred, 
and the puncture made between the umbilicus and the anterior portion 
of the os pubis, it being thought that this position offered less danger of 
injuring the stomach or liver, which is often increased in size on account 
of disease. The under surface of the abdomen is disinfected, and the 
operation performed as above described. 
A bandage may be applied before operation, so that by tightening it 
as the fluid escapes intra-abdominal pressure may be sustained and 
syncope prevented. After operation, bandages prevent secretion of fiesli 
fluid, though unfortunately in dogs they can seldom be kept in place, 
but slide backwards, even if passed over the chest. 
To prevent the return of ascites, the injection of spirit or solution of 
iodine into the peritoneal sac has been recommended, after allowing the 
fluid to discharge ; but the uselessness and danger of this procedure have 
already been shown in human surgery, and it is now scarcely ever used. 
In animals it is not infrequently necessary to repeat the operation, 
HERNIA. 
Hernia or rupture is a condition in which portions of the abdominal 
contents have passed through the abdominal walls, and lie undei the 
skin. Should they pass through the skin, the condition is termed pro¬ 
lapse. Under the older system of nomenclature, the passage of 
abdominal organs through the diaphragm into the thorax was also 
described as hernia (diaphragmatic hernia), and in cattle strangulation 
of the bowel by the spermatic cord was termed pelvic hernia, com 
ditions which will be noticed here, although in the tiue sense of the 
word they belong less to the hernia; than to the mcaiceiations. 
The cause of hernia is sometimes a congenital defect, like too wide an 
inguinal ring or an open umbilicus. Such hernia; aie, theiefoie, eitliei 
congenital, or develop soon after birth. Increase of intra-abdominal 
pressure, frequent coughing, dyspnoea, pressure on the abdomen, or 
development of gas in the bowel (tympanites), all assist their formation, 
while rupture of the abdominal wall directly produces them. Such 
rupture may be produced during parturition, or by excessive exertion, 
severe pressure on the abdomen, or the violent impact of blunt bodies. 
In men external influences, such as the pull of lipomatous new giovtlis 
on the abdominal walls, may induce local pocketing and prepare the way 
for ruptures; but such cases do not appear to have been seen in 
animals. 
