Pediatric emergency medicine trisk 3793 3793

stretching of the hepatic vessels and multiple area of neovascularity (N ). Note marked
stretching and displacement of the inferior vena cava (I ) with patent portal vein (P ). A, aorta.

ABDOMINAL WALL DEFECTS
Inguinal Hernias and Hydroceles
Indirect inguinal hernia is the most common congenital anomaly that is found in
children. It is approximately 10 times more common in males than in females.
There is a strong familial incidence.
Clinical Manifestations
The child with a hernia may present in different ways. The presentation is
determined by the extent of obliteration of the processus vaginalis during
development. A child may have a completely open hernia sac, which extends
from the internal ring to the scrotum, or a segmental obliteration producing a sac
that is narrow at its proximal end, creating a hydrocele of either the tunica
vaginalis or the spermatic cord. The narrowing of the processus allows the
abdominal fluid to seep into the distal portion of the sac. It then becomes
entrapped and produces what is clinically recognized as a hydrocele. It is often
difficult for this fluid to egress through the narrow patent processus vaginalis
back into the abdominal cavity.
At the time of the embryologic closure of the processus vaginalis, many fetuses
will have some fluid trapped around the testicle in the tunica vaginalis. This is
called a physiologic hydrocele, which is a normal newborn finding. In such cases,
the fluid is gradually absorbed in the first 12 months of life. If, however, an infant
or child develops a hydrocele along the cord in the tunica vaginalis sometime
after birth, it must be assumed the processus vaginalis is still patent and in
communication with the peritoneal cavity. This patent processus vaginalis
represents a hernia sac. Surgical closure of the sac and drainage of the hydrocele
are then indicated on an elective basis.
Many infants and children manifest the classical bulge in the inguinal canal
that occurs during straining or crying. This is caused by a loop of intestine
distending into the hernia sac (or may represent the ovary in a female). Usually,

the hernia sac contents reduce into the abdominal cavity when the straining
ceases. If the prolapsing loop of intestine becomes entrapped in the hernia sac, an
incarceration has occurred. This is a true emergency that could eventually lead to
intestinal obstruction and possibly strangulation of the bowel. For easily reduced