Gastric Dilatation-Volvulus (GDV) or Bloat
Gastric dilatation-volvulus (GDV) is a true emergency. It is life-threatening. It begins as a rapid accumulation of air in the stomach causing the stomach to swell. This is the dilatation phase. If left untreated, the stomach may rotate or twist. This is known as torsion or volvulus. When this occurs, the stomach becomes blocked at the esophagus preventing vomiting and blocked at the outlet into the small intestine. Stomach contents become trapped causing further expansion of the stomach. The enlarged stomach presses against nearby blood vessels, compressing them enough to stop the passage of blood in them. The flow of blood from the abdominal organs and lower extremities to the heart is compromised. This, in turn, reduces the flow of blood to many vitals organs. Tissues not receiving oxygen-laden blood will die. This is essentially a form of shock from which most dogs do not recover. The incidence of this disease has increased since 1969. Why remains unknown. To date, no single cause has been proven. Several risk factors have been identified. They include large-breed dogs with deep, narrow chests (e.g. Irish Setter); dogs that eat one or two very large meals a day; dogs that bolt down their food; dog who eat primarily dry dog food; dogs who exercise heavily immediately before or after a meal; and dogs with a fearful or nervous temperament. The latter is being considered because these dogs may tend to bolt down their food and swallow a large amount of air in the process. Stress may also play a role in decreasing gastric motility, the normal action of the stomach to pass semi-digested food into the intestinal tract.
Early signs include pacing, unsuccessful attempts to vomit, swelling or distention of the abdomen (this may or may not be noticeable), excessive salivation, panting or burping. Time is of the essence in seeking treatment before the later stage of shock and its symptoms develop in which the heart begins to fail and the dog becomes more and more unresponsive.
Bloat is most often diagnosed on clinical signs alone. If there is a question as to whether bloat is actually occurring, abdominal radiography should be done.
Treatment must begin as rapidly as possible. A stomach tube may be passed through the dog’s mouth and into the stomach to decompress or let the air, fluid and food out of the stomach. This can only be done if the stomach has not yet twisted and closed off the entry at the bottom of the esophagus. An alternative to a stomach tube is insertion of a large needle through the abdominal wall into the stomach to allow gas to escape. Surgery is the next step. It should be done even if the stomach has only distended. Intravenous fluids for shock treatment and other medications are usually required. The surgery is called a gastropexy and involves suturing or “tacking” the stomach to the ribcage to prevent it from ever twisting again. You should be aware that this surgery will not prevent further episodes of dilatation only the torsion/volvulus. Dogs who have undergone a gastropexy and suffer bloat again will still need immediate treatment to release the gas.
The fatality rate for a dog with a dilated, rotated stomach is about 30%. Even with immediate treatment and surgery, some dogs will die because the stage of shock has progressed too far or they die of post-operative cardiac problems or infection. For dogs that do survive after undergoing gastropexy, 5% will suffer a recurrence of GDV. Dogs who have only had the gas decompressed from their stomachs and not undergone surgery have an 80% rate of recurrence.
MODE OF INHERITANCE:
This is not considered an inherited disease except that general body type does influence incidence.
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