gastric dilitation and volvulus (gdv), bloat and torsion
what is meant by the term 'bloat' in dogs?
this is a term that is synonymous with the more scientific term "gastric dilatation/volvulus." it is often called gdv. that means that a dog's stomach distends with air, twists and cuts off blood flow, to the point that the dog goes into shock and may die. dilatation means that the stomach is distended with air, but it is located in the abdomen in its correct place. volvulus means that the distention is associated with a twisting of the stomach on its longitudinal axis.
simple bloat is where the stomach quite literally fills with air. sometimes, however, because of the way the stomach swings in the body cavity, the ligaments stretch, and the stomach begins to rotate, closing off the openings to the stomach. at that point any air in the stomach is trapped, the pressure cuts off blood circulation, the stomach tissues begin to die and toxins begin to be released. this rotation also compresses one of the major veins carrying blood to the heart, severely depressing normal blood circulation. rotation of the stomach also obstructs blood flow in the vein that delivers nutrients from the small intestine to the liver which produces congestion of the blood vessels, lack of oxygen supply to the tissues and eventual death of these and other abdominal organs (liver, pancreas, small intestines and spleen). all of this can quickly lead to shock and death unless immediate veterinary intervention occurs!! although death is imminent without surgical intervention regardless of the degree of rotation, you have much less time to save your dog when the stomach has done a complete 360 degree rotation than you do if the rotation is 180 degrees or less.
almost every breed of dog has been affected by gdv but it's more commonly seen in large, deep-chested breeds - akitas, great danes, st. bernards, german shepherds, irish wolfhounds, irish setters, and boxers. it is universally agreed that bloat is one of the true surgical emergencies that occurs in dogs.
how or why does this occur?
we really do not know the answer to either of those questions. original theories suggested that it occurred when a dog ate a large meal of dry food and then drank a lot of water. the water caused the dry food to swell. at the same time, the dog was supposed to be engaged in strenuous exercise that included running and jumping. that resulted in the dog's stomach twisting on itself as the heavy organ was jostled about in the abdomen. although that is the most common explanation given, there is no scientific evidence to support this theory. with most dogs experiencing gdv, the stomach is not excessively full of dry food and the dog has not recently engaged in strenuous exercise. the most current theory is that the stomach's contractions lose their regular rhythm and trap air in the stomach; this can cause the twisting event. however, the sequence of events for most cases defies a good explanation.
one theory claims some dogs are born with their stomachs slightly out of position allowing it to twist more easily. another theory speculates that affected dogs are born with impairment of either the esophagus or pylorus, effectively preventing food from leaving the stomach. dogs that gulp food and then exercise heavily may also be at increased risk. some dogs under extreme anxiety suffer "stress-related bloat" by gulping large amounts of air when nervous. in older dogs, tumors of the spleen, stomach, kidney or other internal organs may cause blockage and twisting and subsequently result in bloat. eating indigestible materials like clothing or garbage may also cause bloating. more cases of bloat occur between the months of april and august than at any other time so one can't help but wonder if warm/hot weather can also be a contributing factor. studies have been ongoing at many veterinary schools for decades but the exact cause(s) of bloat remains a mystery.
what are the symptoms?
if you see your dog exhibit any or all of the symptoms listed above, please call your vet at once for instructions and be prepared to transport your dog immediately. more incidences of bloat occur in the early morning hours than at any other time of the day. find out if there's an emergency animal clinic near you - one that's open during the time your regular veterinarian isn't available. if there isn't an emergency clinic near you, discuss your options with your regular vet. please, don't assume your regular vet can and will treat your dog if torsion has occurred!!! ask him or her if they're familiar with gdv and ask how many times they've performed the surgery that may be needed to save your dog's life!! if you're not comfortable with the response, find a veterinarian that is qualified to treat your dog!! death loss due to gdv is very high. often owners delay in getting emergency care for their dog because they're unaware of the seriousness of the condition. unfortunately, once the stomach has undergone volvulus (torsion), many metabolic poisons build up resulting in damage to the stomach wall, liver, spleen and heart muscle. frequently these poisons will cause the heart to stop during surgery or they may circulate for several days post-operatively and continue to pose a threat, as will post-operative infections. with a little luck though, your dog can and will survive.
what is done to save the dog's life?
the presence of a rapidly developing distended abdomen in a large breed dog is enough evidence to make a tentative diagnosis of gdv. a radiograph (x-ray) is used to confirm the diagnosis of dilatation. it can also identify the presence of volvulus, in most cases. there are several important steps that must be taken quickly.
1. shock must be treated with administration of large quantities of intravenous fluids. they must be given quickly; some dogs require more than one intravenous line.
2. pressure must be removed from within the stomach. this may be done with a tube that is passed from the mouth to the stomach. another method is to insert a large bore needle through the skin into the stomach. a third method is to make an incision through the skin into the stomach and to temporarily suture the opened stomach to the skin. the last method is usually done when the dog's condition is so grave that anesthesia and abdominal surgery is not possible.
3. the stomach must be returned to its proper position. this requires abdominal surgery which can be risky because of the dog's condition.
4. the stomach wall must be inspected for areas that may have lost its blood supply. although this is a very bad prognostic sign, the devitalized area(s) of the stomach should be surgically removed.
5. the stomach must be attached to the abdominal wall (gastropexy) to prevent recurrence of gdv. although this is not always successful, this procedure greatly reduces the likelihood of recurrence.
what is the survival rate?
this will largely be determined by the severity of the distention, the degree of shock, how quickly treatment is begun, and the presence of other diseases, especially those involving the heart. approximately 60 percent to 70 percent of the dogs will survive if treatment is started promptly.
after an occurrence of bloat, what can be done as prevention?
the most effective means of prevention is gastropexy, the surgical attachment of the stomach to the body wall. this will not prevent dilatation (bloat), but it will prevent volvulus in most cases.
to avoid surgery after an occurrence of bloat (or prophylactically), the following steps should be taken to minimize the risk factors for bloat:
call your veterinarian or emergency clinic if you have any questions.
faq's - common health problems: the dangers of bloat (gastric dilatation-volvulus - gdv)
dogs of high risk breeds : boxers
bloat is a condition that is more common in
large-chested dog breeds. it often occurs after large dry food meals that are followed by
drinking a lot of water or exercising. essentially, the pet gets a twist or kink in the
intestine, causing vomiting and a gas build up. it comes on rapidly and can be fatal
within hours. here are some answers to common questions about bloat: