Bloat, Gastric Dilatation and Volvulus in Dogs

Gastric Dilatation and Volvulus (GDV) is a life threatening disorder most commonly seen in large, deep-chested dogs, although any dog may be affected.

In its early stage, the stomach fills with gas, causing a simple gastric dilatation or “bloat”. Sometimes, the condition progresses no further than a bloat. A GDV is a progression of the bloat into a volvulus, in which the huge, gas-filled stomach twists upon itself so that both the entrance and exit of the stomach become blocked.

This is a life-threatening emergency that requires surgery to correct.

What causes Gastric Dilatation and Volvulus?

The exact cause is still unknown. The condition is seen most commonly in large breed dogs that eat or drink rapidly and then exercise vigorously.

Additional facts about Gastric Dilatation and Volvulus include:

  • Dogs weighing over 100 pounds have approximately a 20% risk of bloat during their lifetime.
  • Gastric dilatation (bloat), usually without volvulus (twist), occasionally occurs in elderly small dogs.
  • The distended stomach pushes the posterior rib cage so that the dog appears swollen or “bloated”. This is most obvious on the left side and gentle tapping of the swelling just behind the last rib often produces hollow, drum-like sounds.
  • The enlarged stomach presses on the diaphragm and breathing becomes labored.
  • The swollen stomach presses on the larger blood vessels in the abdomen and circulation is seriously compromised, resulting in systemic shock.
  • Ultimately, the dog collapses and the distended abdomen becomes readily apparent as the dog lies on its side.

Factors that may increase the risk of Gastric Dilatation and Volvulus include:

  • Feeding only one meal a day
  • Having a family history of bloat (i.e. a parent or sibling that has suffered from this condition)
  • Eating rapidly
  • Being thin or underweight
  • Having a fearful, anxious or nervous temperament
  • Having a history of aggression toward people or other animals
  • Male dogs are more likely to bloat than females
  • Older dogs (7 – 12 years of age) were the highest risk group in a recent study
  • Moistening dry food particularly if citric acid is listed as a preservative

Is it possible to distinguish between gastric dilatation (GD) and gastric dilatation and volvulus (GDV)?

No. These two conditions often look identical on physical examination. X-rays and other diagnostic tests are necessary to determine if the stomach has twisted.

What is the survival rate?

This depends on many factors; how long the pet has had GDV, the degree of shock, the severity of the condition, cardiac problems, stomach wall necrosis, length of surgery, etc. Even in relatively uncomplicated cases, there is a mortality rate of 15-20% for GDV. In a recent study, if heart arrhythmias were also present at the time of diagnosis, the mortality rate increased to 38%; if tissue damage was severe enough to require removal of part of the stomach, the mortality rate jumped to 28% to 38%; if the spleen was removed, the mortality rate was 32% to 38%.

Please do not hesitate to discuss any concerns you have regarding this serious condition with your veterinarian.