Gastric dilatation-volvulus (GDV) is a very serious condition that occurs in susceptible dogs when the stomach becomes distended with air, and then while dilated, twists on itself. This interferes with the blood supply to the stomach and other digestive organs, and blocks the passage of food, leading to worse bloat. The distended stomach impedes the normal return of blood to the heart, causing drastically reduced cardiac output and a decrease in blood pressure. Blood/oxygen-deprived tissues start to die, releasing toxins into the blood stream which among other adverse effects, cause serious disturbances in heart rhythms (cardiac arrhythmias) - a common cause of death in these dogs.
Simple gastric dilatation does not produce volvulus (twisting) in an otherwise normal stomach. Dogs most susceptible to GDV are the large, deep-chested breeds, in whom the stomach appears to be more mobile within the abdomen. Other factors that increase the risk for GDV include overeating, rapid eating, single daily feeding, high water consumption, stress, and exercise after eating.
It appears that conformation and size are what predispose a particular breed to this disorder, such that breeds with a deeper and narrower chest are most susceptible. Within such a breed, dogs with a higher thoracic depth/width ratio (ie. the deepest, narrowest chests) are the most vulnerable to GDV.
GDV is one of those thankfully rare conditions in which your dog can go from being healthy to critically ill over the course of a few hours. Even with appropriate veterinary care, approximately one third of dogs with this condition will die.
Initiation of GDV occurs when a susceptible dog swallows air while gulping food or water, possibly in association with exercise. You will first notice that your dog is uncomfortable - pacing, restless - and appears bloated. There may be unproductive retching/vomiting. Discomfort progresses to depression and if the dog does not receive treatment, to coma and death. This can all happen within 6 hours or less.
GDV must be diagnosed and treatment initiated quickly if your dog is to survive. The condition is usually readily diagnosed on physical examination.
The two urgent priorities are to remove the gas from the stomach (via stomach tube) and start treatment for shock. Your veterinarian will then perform surgery to reposition the stomach, assess the extent of damage, and do a gastropexy to anchor the stomach to the abdominal wall and prevent recurrence of GDV.
Intensive care is required in the immediate post-operative period when dogs may face a number of life-threatening problems including shock, electrolyte imbalance, cardiac arrhythmias, and wide-spread infection (septicemia).
Prevention: There are some simple things you can do to reduce the chance of bloat, if you have a dog of a susceptible breed. Basically, you want to avoid your dog consuming a large amount of food or water all at once, especially not at the same time as vigorous exercise. Rather than feeding once a day or leaving food always available, feed in divided portions. Have fresh clean water always accessible but take it up at mealtimes (so your dog doesn't gulp it with food). Avoid exercising your dog before and after meal times.
It may be possible to reduce the incidence of GDV in susceptible breeds by selectively breeding dogs with lower thoracic depth/width ratios.
FOR MORE INFORMATION ABOUT THIS DISORDER, PLEASE SEE YOUR VETERINARIAN.
Glickman, L.T., Glickman, N.W., Perez, C.M., et. al. 1994. Analysis of risk factors of gastric dilitation and dilitation-volvulus in dogs. J. Am. Vet. Med. Assoc. vol 24: 1465-1471.
Schaible, R.H., Ziech, J., Glickman, N.W., et. al. 1997. Predisposition to gastric dilitation volvulus in relation to genetics of thoracic conformation in Irish setters. J. Am. Animal Hosp. Assc. vol 33:379-383.