Hernias: Umbilical -
Inguinal & Diaphragmatic Surgeries performed at American
Hernias are very common in human medicine,
especially in males. Hernias in general are a weakness or
opening within a muscle mass that allows other tissues to
pass through. In men, they are usually inguinal hernias, which
are found in the groin area where there is a tiny natural
opening within a band of muscle. When a hernia occurs here,
the opening enlarges and the intestines from the abdominal
area pass through it, producing a swelling immediately under
of hernias in dogs and cats
In pets, there are also hernias involving the muscles
that surround the abdomen and they are commonly found
at two locations. The first site would be in the groin
area on the inner surface of the rear leg - an inguinal
hernia. The second site would be the 'belly button'
where the umbilical cord had connected the puppy to
his mother. A hernia at this location is called an umbilical
hernia. In both cases, abdominal organs such as the
intestines or fat pass through the opening and lie just
beneath the skin.
Another common hernia site in pets involves the internal
muscle that separates the abdomen and chest. That muscle
is called the diaphragm, so the hernia is therefore
referred to as a diaphragmatic hernia. The intestines
and other abdominal organs (such as liver and stomach)
are able to pass through the opening within the diaphragm
into the chest cavity. There they take up a portion
of the space normally occupied by the lungs.
A hernia is, therefore, usually nothing more than an
abnormal opening in a muscle through which other tissues
of the body pass.
The idea that a section of intestine or other structure
might slip through one of these openings and move under
the skin or into a different body cavity (such as the
chest) does not seem like a big problem. However, in
many cases, a hernia that goes untreated can have a
fatal outcome. Usually, the problems that occur are
not caused by the intestines or other organs being in
an abnormal position or from the displacement of other
tissues that are supposed to be there. Rather, in most
instances, a problem arises when the blood supply of
the herniated tissues is affected.
Figure #1 shows a hernia that involves the abdominal
wall and a section of the small intestine. A portion
of the intestine has slipped through a small hole in
the muscular wall. This is exactly how an umbilical
hernia appears. Notice the stricture (abnormal narrowing)
of the intestine itself. This could easily prevent the
passage of food through this section of the intestine,
effectively causing an obstruction or blockage. This
would certainly lead to the death of the animal, if
it were not treated. More importantly, however, please
look at Figure #2. This shows a close-up of the intestinal
wall as it passes through the hernia. Notice how the
blood vessels are twisted and constricted. Blood will
not be able to flow back and forth from between this
portion of the intestine and the rest of the body. It
means that the section of intestine that has passed
through the hole in the abdominal wall will lose its
blood supply. It will be deprived of oxygen and nutrients
and when this occurs, it dies.
The symptoms associated with a hernia, like the one pictured
in Figure 1 and 2 may initially relate to the inability of
food to pass through this constricted section of intestine.
Muscles within the wall of the intestine are responsible for
moving food and water through the organ. Waves of contractions
called peristalsis propel the contents along the length of
the intestine. When an obstruction is encountered, like the
one described, the peristaltic waves reverse direction and
move the food backward through the entire digestive tract.
This results in food and water being vomited. After this portion
of the tract has emptied, the animal usually goes off food
and refuses to eat. They may still drink water because liquids
might be able to pass through the restricted section of the
intestine or be absorbed prior to that point.
Once the blood vessels are affected, however, the clinical
signs change drastically. The area will become swollen and
painful. Without adequate oxygen and nutrients, the intestinal
tissues initially develop cramps just like your leg does when
you cross it and it 'goes to sleep.' And if the flow of blood
is completely lost, cell death occurs. The pain then becomes
severe. The animal will probably develop a fever, become lethargic,
and go completely off food and water. As these tissues break
down, the toxins from bacteria that normally live in the intestine
make their way into the rest of the animal’s body. As
the tissue dies, the affected area turns into an abscess and
many different harmful metabolic waste products are flushed
throughout the animal’s body. All of these substances
(bacterial toxins and metabolic waste products) seriously
affect the various organ systems of the body. Liver and/or
kidney failure are quite common in these situations. Without
treatment, the animal will usually die within 24 to 48 hours.
As an owner, do not take a hernia in your pet lightly. In
many cases, they are disasters just waiting to happen. Do
not buy a puppy that has a hernia unless you have a veterinarian
examine it so you will understand what treatment is necessary
and the potential cost. Some hernias found in young dogs can
wait for repair until the time they are spayed or neutered.
In older dogs, we generally repair a hernia as soon as possible
once they are discovered.
Hernias are surgically repaired by replacing the herniated
(displaced) structures back into their correct position and
then suturing closed the abnormal openings . This often requires
the use of specialized techniques and long-lasting suture
material. We frequently perform this surgery and most pets
recover without complications.
As a note, umbilical hernias in puppies are a genetic or congenital
defect in over 90% of the cases. The disorder is passed from
generation to generation just like the color of the coat or
the animal’s overall size. Very, very rarely are they
caused by trauma or excessive pressures during whelping. Animals
that have a hernia or had a surgical repair of a hernia should
never be used for breeding. Additionally, those adults that
produce puppies with this condition should not be bred again.