Learn the signs, prevention and treatment of this dangerous condition.

Canine bloat, also known as gastric dilatation-volvulus, is a fast-occurring digestive disorder that often affects large-breed dogs with deep, narrow chests. GDV is an extremely painful condition that if left untreated, can cause death within hours. Although certain breeds, such as the Bloodhound, Great Dane, Irish Setter and Standard Poodle, are highly susceptible to bloat, any dog can be stricken.

Bloat (or dilatation) is characterized by a rapid accumulation of gas in the stomach that causes it to enlarge. Dilatation might be followed by volvulus, a twisting or turning of the stomach. When the stomach twists, both the esophagus and the pyloric valve (located at the bottom of the stomach) are crimped. The gas is trapped inside the stomach and the dog is unable to burp or pass gas. Volvulus also blocks food from advancing into the intestines, and prevents the dog from vomiting. As the abdomen expands and distends, the stomach compresses large veins in the abdomen. This restricts blood flow back to the heart. A dog experiencing GDV will typically go into shock and then cardiac arrest within hours after the start of volvulus.

What causes bloat?
In 1994, the Purdue University School of Veterinary Medicine conducted a five-year controlled study of more than 1,900 dogs that did not have a previous history of bloat. Although no one particular event leads to bloat, the study identified several factors that can increase the risk of an episode:

• Deep and narrow chests
• Lean body mass
• A diet that consists of a single, large daily meal, instead of smaller portions in multiple meals
• The tendency to eat quickly
• A diet of dry food that contains fat among the first four ingredients
• A relative that experienced a bloat incident
• Fear, nervousness and aggression

Other theories regarding the cause of bloat include ingesting water during meals or exercising around meal time, but none have been substantiated. “I am not aware of any study that shows that exercise or water intake immediately before or after eating causes bloat in dogs,” says Larry Glickman, V.M.D., Ph.D., who led the 1994 study at Purdue and is now professor of epidemiology at the University of North Carolina School of Medicine in Chapel Hill, N.C.

One traditional measure believed to prevent bloat was raising the dog’s food bowl when eating, but the Purdue Study found the opposite to be true. “We found that when a dog regularly consumes food from a raised food bowl, its risk of bloat increases significantly over time,” Glickman says.

A dog experiencing bloat will exhibit several symptoms:

• Anxiety
• Heavy salivating
• Pacing
• Abdominal swelling after a meal
• Unproductive vomiting
• Biting or licking the stomach area
• Shallow breathing
• Excessive heartbeat

If your dog experiences signs of bloat, immediately rush it to an emergency veterinary clinic or to a veterinarian capable of performing emergency surgery. Once bloat occurs, the clock is ticking. The speed at which treatment is administered determines if a dog survives. Even with early diagnosis and proper treatment, approximately 30 percent of dogs with GDV die or must be euthanized.

Treating bloat begins with decompression, or alleviating the gas pressure. This is usually done by inserting a tube down the dog’s throat into its stomach making a passage to relieve the gas. If a tube can’t be passed because the stomach has twisted, the veterinarian can insert a hypodermic needle in the dog’s stomach through the side of the abdomen to relieve the pressure. If a dog survives decompression, emergency surgery is recommended to evaluate the health of the stomach and to ensure it returns to its normal position.

Once a dog’s anatomy has been restored, the most important part of bloat surgery is gastropexy, a procedure which staples or anchors the stomach into its normal position and prevents it from twisting in the future. Although dogs that have had gastropexy might experience bloat again, it’s impossible for the stomach to rotate, which gives the dog a better chance of surviving bloat episodes.

Know the signs
Bloat is a life-threatening condition and extremely serious. Owners of susceptible breeds should be knowledgeable about the signs of the disease, since early and prompt treatment can greatly improve the outcome.

Current recommendations for preventing bloat include feeding frequent small meals rather than one large meal, particularly in high-risk breeds; not feeding in a raised food bowl; not breeding dogs that have a history of bloat; and performing a preventive gastropexy at an early age in high-risk breeds.

Anti-Gas Drugs
Some pet owners believe that administering human over-the-counter anti-gas drugs that contain simethicone to a dog experiencing bloat will help save its life until it gets to a veterinarian. However, not all experts agree.

“If an owner thinks their dog is developing bloat, the highest priority is to get it to a veterinarian as fast as possible,” Glickman says. “The veterinarian can immediately confirm a diagnosis of GDV with a radiograph and can begin shock therapy, if needed. Giving an anti-gas drug wastes valuable time and is unlikely to help in any way. The filling of the stomach is not caused by production of gas, but rather by a dog swallowing air.”

Preventative Gastropexy
In breeds that are considered high risk for bloat, experts recommend performing a preventative gastropexy instead of waiting for an emergency to occur. This surgery is often performed at the time of spaying or neutering to reduce the number of times a dog needs to be anesthetized.

“Prophylactic gastropexy will prevent a dog’s stomach from rotating when it bloats and therefore, significantly reduces mortality in high-risk breeds,” says Larry Glickman, V.M.D., Ph.D., who led the 1994 bloat study at Purdue. “A gastropexy can be done at any time to prevent gastric tension, but the earlier the better.”

Glickman adds that a dog should be fully developed anatomically before this surgery is performed, probably no earlier than 6 months of age.

The prophylactic procedure, which is performed laparoscopically, offers many benefits:

• Is minimally invasive with only two small incisions
• Is followed by a quicker recovery than an emergency gastropexy
• Requires shorter surgery and less anesthesia than an emergency gastopexy
• Is less expensive than treating life-threatening GDV