(Gastric Dilatation Volvulus or Stomach Torsion)

Information compiled by
Guardian Angels Mary Jane Mauch, Rita Ryder, and Roberta Wade


Fast Facts

General information:

1. Dogs with bloat nearly always are between four and seven years of age. Two-thirds are males.

2. It usually affects dogs of the larger, deeper-chested breeds: Great Danes, German Shepherds,
Saint Bernards, Labrador Retrievers, Irish Wolfhounds, Great Pyrenees, Boxers, Weimaraners, Old English Sheepdogs, Irish Setters, Doberman Pinschers,and others of large size (58 pounds was the average size in one study).  It rarely occurs in small breeds
, but has been known to occur even in Dachshunds who are also among the breeds having a deep chest.  Beagles and other breeds and/or dogs who eat their food rapidly tend to be at greater risk also.

3. Dogs who bloat tend to eat large quantities of dry kibble.

4. They exercise vigorously after eating and tend to drink water in large amounts after meals.

5. They may have a history of digestive upsets (gastritis).

6. There may be a familial association with other dogs who have bloated, but this has not been substantiated.

7. There may be an association between gastric volvulus dilatation and Inflammatory Bowel Disease, but the relationship in unclear.

Factors Increasing the Risk of Bloating:

Feeding only one meal a day

Having closely related family members with a history of bloat

Eating rapidly

Being thin or underweight

Fearful or anxious temperament

History of aggression towards people or other dogs

Male dogs are more likely to bloat than females

Older dogs (7 - 12 years) were the highest risk group

Factors Decreasing the Risk of Bloat:

Inclusion of canned dog food in the diet

Inclusion of healthy home-cooking in the diet

Happy or easy-going temperament

Eating 2 or more meals per day

Minimize exercise and/or excitement before and after meals

Bloat (Gastric Dilatation Volvulus or Stomach Torsion)
The Long Version

Bloat is a life-threatening emergency that affects dogs in the prime of life.  The mortality rate for gastric volvulus approaches 50 percent.  Early recognition and treatment are the keys to survival.

Bloat actually refers to two conditions:  one is gastric dilatation, in which the stomach distends with gas and fluid and the second is volvulus, in which the distended stomach rotates on its long axis.  Because the spleen is attached to the wall of the stomach, if the stomach rotates, the spleen does also.  Gastric dilatation may or may not be complicated by volvulus.  If volvulus occurs, the stomach may twist 180 degrees or less (technically called a torsion).  An actual volvulus is a twist of 180 degrees to 360 degrees or more.

When actual twisting occurs, the stomach itself is essentially pinched off from the rest of the digestive tract.  The gastroesophageal junction becomes twisted and obstructed, preventing the dog from belching and/or vomiting.   Gas and fluid are trapped in the closed-off stomach, which can become hugely distended as the contents in the stomach ferment.  When the stomach is twisted, this seals all outlets that could allow the gas to escape.  Even more gas is produced as the distressed stomach churns and secretes more digestive juices in response to the irritation.  Interference with blood circulation results in necrosis (death) of the wall of the stomach. 

This sequence produces a number of other problems, including acute dehydration, bacterial septicemia, circulatory shock, cardiac arrhythmias, gastric perforation, peritonitis and death.

Bloat can occur in any dog at any age, but typically occurs in middle-aged to older dogs.  There may be a familial association with other dogs who have bloated.  Large-breed dogs with deep chests are anatomically predisposed.  These breeds include the Great Dane, German Shepherd, Saint Bernard, Labrador Retriever, Irish Wolfhound, Great Pyrenees, Boxer, Weimaraner, Old English Sheepdog, Irish Setter, Bloodhound, Doberman Pinscher, and Standard Poodle.  Chinese Shar-Pei and Basset Hounds have the highest incidence among midsize dogs.  Small dogs are rarely affected, but no breed is totally without risk.

Bloat develops suddenly, usually in a healthy, active dog.  The dog may have just eaten a large meal, exercised vigorously before or after eating, or drunk a large amount of water immediately after eating. 

Signs of Bloat

The classic signs of bloat are restlessness and pacing, salivation, retching, unproductive attempts to vomit and enlargement of the abdomen.  The dog may whine or groan when you press on his belly.  Thumping the abdomen produces a hollow drum sound.

Unfortunately, not all cases of bloat present with typical signs.  In early bloat the dog’s stomach may not appear distended, but the abdomen usually feels slightly tight.  The dog appears lethargic, obviously uncomfortable, walks in a stiff-legged fashion, hangs his head, but may not look extremely anxious or distressed.  Early on it is not possible to distinguish dilatation from volvulus.

Late signs (those of impending shock) include pale gums and tongue, delayed capillary refill time (the gums do not “pink up” quickly when gently pressed), rapid heart rate, weak pulse, rapid labored breathing, weakness and collapse.

If the dog is able to belch or vomit, quite likely the problem is not due to a volvulus, but this can ONLY be determined by veterinary examination.


Uncomplicated gastric dilatation is relieved by passing a long rubber or plastic tube through the dog’s mouth into the stomach.  This is also the quickest way to confirm a diagnosis of bloat.  As the tube enters the dog’s stomach, there should be a rush of air and fluid from the tube, bringing relief.  The stomach is then washed out.  The dog should not be allowed to eat or drink for the first 36 hours, and will need to be supported with intravenous fluids.  If symptoms do not return, the diet can be gradually restored.

Being able to pass a tube does not always rule out volvulus.  Occasionally the tube passes even though the stomach is twisted.  A diagnosis of dilatation or volvulus is best confirmed by X-rays of the abdomen.

If the dog has a volvulus, emergency surgery is required as soon as the dog is able to tolerate the anesthetic.  The goals are to reposition the stomach and spleen, or to remove the spleen and part of the stomach if these organs have undergone necrosis.  Future recurrence can often be prevented by suturing the wall of the stomach to the abdominal wall (a procedure called gastropexy).  This important step keeps the stomach in position and prevents it from twisting.

Preventing Bloat

Dogs that respond to non-surgical treatment have a 70 percent chance of having another episode of bloat.  Some of these episodes can be prevented by following these practices:

Dividing the day’s rations into three or more equal feedings.

Restrict access to water for one hour before and after meals.

Never let your dog drink a large amount of water all at once.

Avoid strenuous exercise on a full stomach – recommendations include restricting exercise for 60-90 minutes following a meal.

Be aware of the early signs and seek prompt veterinary attention whenever you suspect bloat.

Also see:

Canine Medicine and Therapeutics, British Small Animal Veterinary Association, 1991.
Caring for Your Older Dog
, Chris C. Pinney, DVM.
Dog Owner’s Home Veterinary Handbook
, 3rd Edition, James M. Griffin, MD & Liisa D. Carlson, DVM, 2000.
Kirk and Bistner’s Handbook of Veterinary Procedures and Emergency Treatment
, 1995.
Merck Veterinary Manual
, 8th Edition.
Veterinary Emergency Medicine Secrets
, Wayne E. Wingfield, DVM, MS, 1997.