The Sudden Killer
What is bloat?
The medical term for bloat is gastric dilatation-volvulus (GDV). It is a life-threatening condition in dogs where the stomach fills with gas, food or fluid, distends, and then twists on itself. The twisting cuts off the blood supply to the stomach and other organs, causing shock, organ damage and potentially death if not treated immediately.
GDV develops without warning and can progress quickly. It is always an emergency.
Stomach distension alone is referred to as “simple bloat,” or gastric dilatation. Simple bloating can occur on its own and may resolve on its own. Bloat without twisting can still be life threatening, but the risk depends on the severity and the duration. In some cases, it can last for hours without becoming life threatening.
The problem is that a simple bloat can progress to a GDV, where the stomach twists and flips (volvulus), at any time. It is difficult to determine when that happens. It makes monitoring a bloat condition at home a very dangerous thing for an owner to do.
As the stomach expands, it puts pressure on several large arteries and veins. Blood supply is cut off to the stomach, toxic products build up, and tissues begin to die. Dogs can go into shock very quickly once GDV occurs, and every minute without treatment increases the risk of further damage and potentially death.
What causes bloat?
Bloat can occur at any age, but is most often seen in middle-aged dogs. Research shows that the risk increases 20 percent for each year of age. Nearly all breeds have been reported to have had gastric dilatation (with or without volvulus), but the condition is seen most commonly in large breeds with deep chests. These dogs are normally much taller than they are wide, creating a high “height to width ratio.” Using this formula, Great Danes are eight times more likely to bloat than dogs with a low height-to-width ratio.
Despite continuing research, the cause of bloat is not known. Some of the risk factors that are thought to contribute to bloat include eating large meals quickly, and drinking a large quantity of water in a short period of time. Intense physical activity after a meal can contribute to GDV.
Feeding from raised food bowls was once recommended as a way to prevent bloat, but is now seen as a possible contributing factor, as it affects the natural position of the stomach.
Stress or anxiety can trigger GDV in some dogs. Anxious dogs are thought to be more prone, as are dogs in stressful situations or environments such as boarding kennels.
What are the signs of bloat?
GDV develops without warning and can progress very quickly. Recognizing the early signs is essential to increasing the chances your dog will survive. The abdomen will appear swollen and tight, like a drum. The dog may retch and attempt to vomit without producing anything.
Some dogs will drool excessively and are restless, agitated or unable to find a comfortable position. Their gums are pale, and the dog may exhibit other signs of shock, including weakness, rapid breathing and collapse.
Based on the above symptoms, your veterinarian will suspect GDV. Radiographs of the abdomen will confirm the diagnosis by showing the dilated and twisted stomach.
What is the treatment for bloat?
Treatment for GDV should be sought out as soon as possible to increase the dog’s chance of survival. The severity of the case determines the treatment recommendation for the affected dog. Once the diagnosis is confirmed with an X-ray, the next step is to restore the circulating blood volume with intravenous fluids and to decompress the stomach to relieve as much gas pressure as possible.
Rapid fluid replacement is achieved by placing one or more large-bore (16 to 18 gauge) intravenous catheters in the jugular vein or the veins of the front legs. Electrolyte fluids are administered to treat shock.
Initial decompression attempts should be made with a stomach tube, which can be performed under mild sedation. A stomach tube is measured from the tip of the nose to the last rib and marked with tape. The tube must not be inserted beyond this marking. The lubricated tube is introduced into the mouth, which is held open with a mouth speculum or a roll of tape. Once the tube enters the stomach, gas rapidly escapes.
Successful passage of a stomach tube does not mean the stomach is not twisted, although in cases of volvulus, it is usually impossible to pass the tube into the stomach. After gas and stomach contents are released from the stomach through the tube, the stomach should be lavaged (washed) with warm water.
If the stomach tube cannot be readily passed, a large-bore needle is inserted through the skin and body wall into the stomach on the right side of the body just behind the last rib. This method of decompression is termed “trocharization.” The sound of hissing gas escaping through the needle indicates the proper placement of the needle in the stomach.
Next, surgery is required to untwist the stomach and return it to its normal position. Surgery also allows the veterinarian to assess the amount of damage to internal organs caused by the lack of blood flow due to the volvulus. Any damaged tissue will be removed. In extreme cases where the condition has been left untreated for a longer time period, there may be too little healthy tissue to salvage. These cases have a poor outcome.
Generally, a gastropexy, where the stomach is sutured to the abdominal wall, is also performed during the surgery. This procedure is designed to keep the stomach in place and prevent twisting of the stomach if bloat occurs again. Dogs that have had a gastropexy, or “stomach tack,” may bloat, but they will not twist, and the bloat can usually be resolved by passing a stomach tube alone. This greatly increases the chances for a full recovery.
How can I prevent my dog from bloating?
There are some preventive measures that can be taken to reduce the risk of bloat. Feeding smaller meals more frequently reduces the amount of gas produced in the stomach. Restrict activity for one to two hours after meal time and avoid any forms of strenuous exercise on a full stomach. Never let your dog drink a large amount of water all at once. Create a calm environment for your dog.
Know where the nearest 24-hour veterinary emergency facility is located in the event that your regular veterinarian is not available after hours or does not have experience handling this condition. For some reason, bloats rarely occur during daylight hours. Since bloats are so common at night or the wee hours of the morning, emergency veterinarians are much better prepared to handle these cases. Time is of the essence when dealing with cases of bloat, and the sooner your dog receives veterinary care, the better the chance for a full recovery.
None of these measures will guarantee that your dog will not bloat, but they may help reduce the severity of the problem.
Are there over-the-counter products to help prevent bloat?
While some over-the-counter (OTC) products might be mentioned in discussions about bloat prevention in dogs, it is important to understand that bloat (GDV) is a life-threatening emergency that requires immediate veterinary attention.
There are no home remedies or supplements that are safe and effective to treat bloat once it has occurred. However, some OTC products may be used with other preventive measures to help reduce the risk of your dog developing bloat.
Simethicone (e.g., Gas-X) is an anti-foaming agent that may help break up gas bubbles in the digestive tract, potentially offering temporary relief for a mild bloat episode. It does not prevent or treat GDV.
Products containing dimethicone and silicon dioxide (e.g., DogZymes Bloat Buster) relieve bloating and gas by breaking down gas bubbles. Safe use in pregnant dogs or dogs intended for breeding has not been proven.
Probiotics can promote healthy digestion and may reduce bloating.
Gallic acid contains plant polyphenol, which has properties that support gut health and reduce inflammation.
Immunoglobulins (IgY) are derived from chicken egg yolk. They support the immune system and reduce the risk of secondary complications that could contribute to bloat.