540 — Dr. Marty Greer’s Deep Dive on Umbilical Hernias

Umbilical Hernias – What are they and what does this mean?
Dr. Marty Greer, DVM shares a deep dive into the question of hernias, different types, and whether dogs with hernias should be included in breeding programs.

By Dr. Marty Greer, DVM

An umbilical hernia is a weakness or opening in the muscle wall of the abdomen where the umbilical blood vessels pass prior to birth. Frequently abdominal fat is in the hernia but the skin is intact across the hernia, so there are no exposed abdominal organs. The fat may be omentum or part of the falciform ligament.

There are several disorders seen in mammals that are similar to an umbilical hernia and may add confusion to the discussion.
Other types of hernias
Gastroschisis is when a puppy’s intestines protrude outside abdomen through an opening off to the right side of the belly button/umbilicus with a bridge of skin between the umbilicus and defect. The intestines and abdominal contents are not covered by a protective membrane. Because the intestines are not covered by a sac, they can be damaged by exposure to amniotic fluid in utero, which causes inflammation and irritation of the intestine.  This can result in complications such as problems with movements of the intestines, scar tissue, and intestinal obstruction. It is also difficult to keep the intestines and other organs sterile, moist, contained, and undamaged during birth and handling shortly after birth.

Omphalocele occurs when the newborn pup’s intestines, liver or other organs protrude outside the abdomen though the umbilicus. Embryologically, as the puppy develops during the first trimmest of pregnancy, the intestines get longer and push out from the belly into the umbilical cord. The intestines normally go back into the belly. If this does not happen, an omphalocele occurs. The omphalocele can be small, with only some of the intestines outside of the belly, or it can be large, with many organs outside of the belly.

In this situation, the organs are covered with a thin, transparent sac of peritoneal tissue. There are often other associated birth defects including heart and kidney defects. Additionally, the abdominal cavity may not be large enough to accommodate the organs when replacing them surgically. In humans, it is associated with heart and neural tube defects as well as other genetic syndromes. An omphalocele is worse than gastroschisis – it has more associated anomalies and a higher rate of mortality than gastroschisis.

When a puppy is born with intestines exposed, whether an omphalocele or gastroschisis, immediate surgery is necessary. If the pup is born at the veterinary hospital, there is a better chance of successful interventional surgery. However, despite the best efforts of the veterinary team, some pups cannot or should not be saved. Surgery includes protecting the organs while transporting and preparing for surgery, keeping more intestines from pushing out of the abdominal cavity while handling, keeping the intestines sterile, and protected from damage, anesthesia of the newborn pup, enlarging the abdominal wall defect to reposition organs into the abdominal cavity, appropriate suture techniques, post op antibiotics, and post op pain medications.

For most pups born at home, this cannot be accomplished. For some pups born by c-section, this can be accomplished with quick thinking veterinary team members, a skilled surgeon, owners willing to put forth the money and effort, no additional genetic disorders, and a lot of luck.

Other hernias seen in humans and animals include inguinal hernias (in the groin region), diaphragmatic hernias, peritoneal-pericardia diaphragmatic hernias (PPHD) and traumatic hernias anywhere on the body cavity. Inguinal hernias are second to umbilical hernias in frequency. An open thoracic wall rarely occurs. In this case, the pup can rarely be saved as there is usually inadequate chest wall (ribs and skin) to close. Additionally,...