Gastric dilatation/volvulus (GDV) is a serious life-threatening condition that develops very quickly. Without quick intervention, most dogs are lost once they develop this problem.
The cause is not well understood. Large deep-chested breeds (Great Danes, Mastiffs, Fox Hounds, others) are more commonly affected, but the problem can occur in any breed, even small dogs. The presence of food in the stomach with extreme activity after eating seems to put a dog at risk, so a likely scenario would be a large dog playing hard right after eating.
Dilatation describes a stomach that is distended or enlarged, and the dilatation part of the problem occurs first (“bloat”). A stomach dilated with either food or gas behaves differently in the abdomen and is more likely to twist, which is the volvulus part of the equation. Imagine holding a sock by each end. Enlarge the heel portion to get the dilatation. The twisting motion can then occur by flipping the dangling middle around in a circle. Twisting can also occur by exchanging the position of your right and left hands. Some cases will have both types of twists at the same time. As the twisting occurs, blood flow is kinked off. At this point the stomach can’t empty itself but continues to seep fluid into it’s lumen, and gas increases. These stomachs become extremely large and press on the heart and lungs through the diaphragm, leading to decreased heart function and shock. The blood supply to the spleen is closely related to that of the stomach and the spleen becomes quickly compromised. Oftentimes a splenectomy is required at surgery in addition to the correction of the stomach displacement.
Owners will see a variety of signs, including depression, drooling, vomiting or attempts to vomit, defecation and straining to defecate. Some dogs will stand with forelimbs positioned far forward and their belly low to the ground. A quickly enlarging abdomen is sometimes seen, an ominous sign. Many owners report a foreboding sense of something wrong as the only initial sign noted. This is truly a condition when minutes count, and these dogs must be assessed quickly.
Diagnosis is by x-ray. If only dilatation is present, passage of a stomach tube and removal of gas may correct the condition. If not, surgery is the only option, and must be done quickly. Post-operative monitoring is very important. As the stomach is untwisted, sequestered electrolytes and toxins are released to be absorbed into the system, and these patients are prone to cardiac arrhythmia. As a result, many of these patients must be managed at a referral center with 24 hour care for a day or two.
Prevention involves slowing food intake and preventing extreme exercise immediately after eating. Some believe that elevating the food bowl may help prevent the disorder, while others now believe that may predispose your dog to the problem. Gastropexy involves surgically anchoring the stomach to prevent twisting. This is easily done during a spay but requires an involved surgery otherwise. Gastropexy prevents the twisting part of the problem but not the dilatation (“bloat”). Again, the mechanism of GDV is poorly understood. Some cases defy explanation as to why they occur.