GASTRIC TORSION
IN DOGS
by Dudley E. Johnson, M.V.Sc.
Professor of Surgery,
University of Pennsylvannia
Torsion of the stomach in the dog is characterized by
life-endangering distension of the stomach with gas; the
stomach is usually found to be severely dilated and
congested, and often to have rotated about an axis in
the plane of the esophagus.
There are many unknown features of this disease. Even
the correct mane for the disease is not known. It is
commonly called torsion of the stomach; however, many
veterinarians, including the author, believe the primary
condition is not torsion, but distension or dilation of
the stomach with gas. This distension may or may not be
followed by torsion or twisting of the stomach.
Incidence
Torsion of the stomach is seen most commonly in large
breeds including the Great Dane and Bloodhound, as well
as some of the intermediate size breeds. Most people
agree it is a serious problem in the first-two named
breeds. There does not appear to be any association with
the sex or the age of the animal. It has been reported
in young adults as well as fully mature dogs. There is
no doubt it can occur suddenly after eating in a
previously healthy dog.
The Cause of Torsion of the Stomach
A commonly expressed explanation is that the disease
is purely a mechanical twist of the stomach. The
stomach, containing some comparatively heavy food
material, is pictured as swinging in a pendulum-like
fashion. Then, as a result of a sudden jump from a high
bench or from rolling or playing, the pendulum is swung
completely around the point of fixation of the stomach,
the point where the esophagus passes through the
diaphragm, giving rise to a twist.
This occludes both the entrance to and the exit from
the stomach so that gas, which is produced in the
stomach, cannot escape, giving rise to the distension.
As stated previously, there is considerable doubt
concerning the validity of this explanation.
In criticism of this mechanical theory, several
objections can be raised. In many cases, there is no
evidence that a sudden or vigorous movement of the dog
after feeding has occurred. In addition, the contents of
the stomach are not such that would facilitate a
pendulum-like movement. In the normal, tightly packed,
abdominal cavity of the dog, the tonicity of the
abdominal muscles, the shortness of the gut, and the
normal absence of much gas or fluid, tend to preclude
the free mobility visualized for the stomach.
In addition, it has been shown experimentally if the
stomach of the dog is distended with air by means of a
stomach tube, the stomach eventually twists in either a
clockwise or counter-clockwise direction, depending on
the position of the spleen at the onset of distension.
If the previous theory is correct, there must be some
factor which causes the initial distension of the
stomach. This factor is not known, but it is probably
due to a condition which causes atony or paralysis of
the wall of the stomach associated with a large meal and
then gas production. Much of the gas found in the
stomach could be caused by swallowing air.
The Development of the Disease in the Dog
According to the theory that distension is the
primary condition, following distension with gas, the
stomach rotates in a clockwise or counter-clockwise
direction. The dog is usually severely ill, and can die
within one or two hours. The stomach is severely
distended, the wall of the stomach is congested, and may
even be deprived of blood. The spleen is also twisted
and enlarged.
A second situation can occur which is not so serious;
the condition is more chronic, and may last several
days. Some dogs eventually become severely distended,
and may die; however, many recover spontaneously.
What Causes the Death of the Dog?
This condition in the dog has a sudden onset, usually
within one to two hours of eating a large meal. The dog
is first breathless and, if examined closely, the
abdomen is excessively large.
The dog will stand, lie still, or move only with
caution. He will generally pass feces and gas so that
eventually the entire gut with the exception of the
stomach has been emptied. There are often attempts at
vomiting although these attempts are rarely successful.
In a period varying from one-half to three hours, the
stomach becomes grossly distended, and there is severe
dyspnea, or difficulty in breathing. The dog may live up
to 36 hours but many will die within one to two hours.
There are several explanations for the rapid onset of
severe signs and rapid death. It has long been suggested
one of the important aspects is the stomach pressing
forward on the diaphragm thus compressing the lungs so
that the animal has difficulty in breathing. There is
experimental and clinical evidence, however, that the
rapid development of severe signs can be better
explained by the pressure of the enlarged stomach on the
vena cava, the large vein which carries blood to the
heart from the abdomen and hind legs. As a result of
this pressure, there is an inadequate amount of blood
returning to the heart, which cannot function
effectively as a pump, and therefore, the blood pressure
of the animal falls. This produces shock and rapid
death. Other factors contribute to a lessor degree to
the development of the clinical signs. There is a loss
of fluids and electrolytes from the body into the
distended gut, and there probably is some pressure by
the distended stomach on the lungs, interfering with
their function.
It can be seen from this discussion of the cause of
death in torsion of the stomach, that the first priority
in the treatment of torsion of the stomach must be
relief of the distension.
Management of the Dog with Torsion of the
Stomach
This is one of the true emergencies in veterinary
medicine, and treatment must be instituted immediately
if the animal is to survive. If the dog cannot be
treated immediately by a veterinarian, the owner may be
forced to render first aid to his dog. This is
difficult, and there is no uniformly successful method
to relieve the distension. In some dogs, a stomach tube
can be passed. This can be done by the owner.
Unfortunately, it is not possible to do this in dogs
with major torsion of the stomach since the entrance
into the stomach is obstructed by the twist in the
esophagus. Some owners puncture the stomach with a
large-bore needle so that the gas will escape. It is
probably best to do this on the right side of the dog
over the point of greatest distension. Again,
unfortunately, this is not always successful. The needle
can become obstructed by stomach contents, and there
maybe a leakage of fluids and gas into the abdominal
cavity with risk of peritonitis. If the animal is
severely affected, the owner may have no choice but to
attempt one of these methods to relieve the distension.
The dog should be treated by a veterinarian as soon
as possible. Unfortunately, there has been insufficient
experimental work done by veterinarians on the treatment
of torsion of the stomach, and opinions vary on the
correct form of therapy.
Many veterinarians advise immediate anesthesia and
surgery to relieve the distension and the twist of the
stomach. If large volumes of fluids and electrolytes are
given by intravenous injection before and during the
operation, reasonably good results can be expected.
More satisfactory results have been obtained by a
method in which the distension is relieved by a simple
surgical procedure. This is later followed by correction
of the torsion when the dog is no longer in shock and
better able to withstand anesthesia and surgery. This is
the method recommended by this author. A small opening
is made into the stomach using a local anesthesia. The
wall of the stomach is sutured to the skin so that
leakage into the abdominal cavity with subsequent
peritonitis cannot occur. Fluid and electrolytes are
given by intravenous injection; surgery is performed
later to close the hole in the stomach and reposition
the stomach, if necessary.
Strict control of food and water intake for many days
after surgery is needed to avoid a recurrence of the
condition.
Prevention
The treatment of torsion of the stomach is
unsatisfactory for two reasons. First, the condition
develops so quickly that the animal can die in such a
short time that many dogs die before treatment can be
instituted. Second, it is not possible to save all
animals with any of the presently accepted forms of
treatment. Using the method in which the distension is
relieved and the torsion corrected at a later date, it
is expected that 75 to 80 % of dogs should survive. Some
dogs are so close to death before treatment that they
cannot be saved, and in others, the stomach wall is
severely injured by lack of blood supply so that
recovery cannot occur.
Therefore, we should direct our attention to
prevention of this condition. Unfortunately, there are
not generally accepted methods for prevention, and much
investigative work is needed.
In some large populations of dogs, such as those in
the armed forces, a high incidence of torsion of the
stomach has been seen with certain feeding regimens. In
many cases, the condition disappears when these dogs are
given food ad lib., that is, the dogs have access to a
large amount of food so that the dog may eat a small
amount of food on many occasions during the day.
Obviously, with this management system, the dog has no
incentive to eat one large meal at any given time and he
does not eat hurriedly.
The most common advice given to owners of large breed
dogs is based on experiences such as the one described
previously. If there is a high risk, it is best to avoid
one large meal per day. The dog should be fed at least
twice daily; he should be discouraged from eating
rapidly, and he should not be allowed to play actively
before and after feeding. The dog should have access to
water continuously so there is less chance he will drink
a large amount immediately after eating.
It seems there is a high risk of torsion of the
stomach if the animal is given one feeding a day, the
dog is allowed to drink and to indulge in vigorous
exercise after eating. All these factors should be
avoided.
Certain drugs that alter the mobility of the
gastrointestinal tract have been advocated to prevent
gastric torsion. There is no experimental or clinical
evidence that any of the presently available drugs is
useful. An operation known as pyloroplasty has been
advocated by some to increase the size of the exit
opening in the stomach. Again, there are no reports in
the scientific literature that this procedure should be
used.