IRISH WOLFHOUND SOCIETY OF IRELAND

Canine Bloat
by Dr. John J. Rutherford III, D.V.M.

Bloat is a serious, life threatening disease in dogs. Bloat is actually two conditions that come under the heading of one syndrome. First there is "simple" bloat or gastric dilatation; second is bloat with twisting of the stomach or gastric dilatation and volvulus. Veterinarians use the abbreviations GD and GDV to describe these clinically. I usually think of these as two syndromes in which one becomes the other; gastric dilatation becoming gastric dilatation and volvulus. So the line between the two is not exactly clear.

What is Bloat?

What are we actually talking about here? Clinically, bloat is when the stomach fills with gas and becomes distended, but the dog cannot burp or relieve the pressure exerted by the gas. Bloat with twisting or GDV is when the dog's stomach fills with gas (and often fluid) and twists 180 to 360 degrees on it's axis between the esophagus and duodenum or the entrance and exit parts of the stomach. When "simple bloat" or gastric dilatation occurs and the stomach swells, a great deal of pressure is put upon the surrounding organs including the liver and lungs interfering with the dog's ability to breath, and the blood supply to the stomach wall is decreased. This is very painful for the dog and quickly becomes a medical emergency. When bloat is complicated by twisting, gastric dilatation, and volvulus, the situation worsens rapidly. In addition to the pressure exerted by the gas distending the stomach, the twisting stops the blood supply to the stomach wall and the tissues themselves begin to die.

Signs of Bloat

The signs of bloat can be subtle at first: restlessness being the most likely first indication of a problem as the distention and pain increases. Drooling, retching or gagging (but not vomiting up stomach contents) will occur and by the time you recognize that your dog's stomach is distended, you have a serious medical emergency on your hands. You need to seek veterinary care immediately! The faster the distention and/or twisting can be corrected, the better the dog's chances of survival. Also, these conditions are extremely painful!
Initial treatment for dogs that are bloated is aimed at correcting shock with rapid fluid infusion, pain relief, and drugs used to restore circulatory balance. The distention should be relieved as quickly as possible also. X-rays are usually taken during the course of initial treatment to determine if twisting or volvulus has occurred. If so, the dog is bound for immediate surgery. If no twisting is found, medical treatment may suffice
Following are more of the signs you may see if your dog is undergoing this problem. The list of possible signs includes any indication that your dog is uncomfortable, related to its stomach or abdomen. Owners who have witnessed the process are fairly intuitive as to what is occurring. If you have a dog of the kind mentioned below, please DO NOT hesitate to call your veterinarian immediately. In the following scenario, you should assume the worst and call:
Your dog eats a meal of dry kibble followed by a large drink of water and then is running, playing, rolling around, etc. (just prior to the onset of bloat symptoms)

Breeds Likely to Suffer Bloat

What kinds of dogs are most likely to suffer from bloat? In general, any kind of large breed and deep-chested breed (Great Danes, Saint Bernards, Irish Wolfhounds, Scottish Deerhounds, Great Pyrenees, Labrador Retrievers, Golden Retrievers, Boxers, German Shepherds to name a few.) Be aware that any dog could possibly bloat at any age. I have seen GDV in a six-month-old Australian Shepherd puppy. Smaller, "rounder" dogs are less likely to suffer bloat, however.

Treatment

How are these problems managed medically or surgically? "Simple" bloat is usually relieved by passing an oro-gastric tube (stomach tube).

 Once the gas distention is relieved, the stomach is then "pumped". The food and fluid contents are flushed out usually with heavy sedation or general anesthesia following initial treatment, supportive care and pain relief are normally provided so a hospital stay to receive intravenous fluids and appropriate medications is usually necessary. With GDV, once a twist is recognized, the patient is almost always an emergency surgical case. The delicate balance here is to anesthetize and perform major abdominal surgery on a patient who is often in shock. It is always a judgment call but not doing surgery will be rapidly fatal.
My subjective suggestions here involves the following when faced with the decision about surgery. It is better to have an inexperienced veterinarian perform the surgery than to wait for an experienced surgeon. Time is absolutely critical in treating GDV. Also, owners need to be aware of a phenomenon that can occur after surgery. Unfortunately, some dogs that have survived surgery and seem fine, will die suddenly in the three- to five-day (give or take a day) post-operative period. What apparently occurs is sudden heart stoppage due to a group of chemicals known collectively as "myocardial depressant factors". These chemicals are formed by tissues and bacteria that occur in organ tissue that has had an interruption of its blood supply. The chemicals build up to a point where they are toxic to the heart muscle cells. This can occur in any post-operative GDV patient, even those treated by very experienced surgeons. Antibiotics and other drugs often have no effect on the production of depression factors.
What does a surgeon actually do during an operation to repair GDV? After entering the abdomen, the stomach is untwisted and evaluated for blood flow. If portions of the stomach don't have a good blood supply, the tissues are rejected and removed. This is a surgical decision process and newer high-tech ways of deciding which tissues will survive can help the surgeon. It still boils down to educated guessing. Sometimes the spleen is found to be compromised and is removed. At this point the surgeon will perform one of the various procedures designed to prevent the stomach from twisting again at a later date. Probably the most common is a procedure know as a belt loop gastroplexy where a strip of stomach wall is passed around a rib and secured with sutures.

Which procedure is chosen will depend on the surgeon's experience and the specific surgical situation he or she is faced with in a specific patient.

Post-Operative Care

Post-operatively the patient is monitored carefully, i.e., surgical intensive care.
The capabilities of the veterinary support staff are very, very important here. These patients need constant monitoring and aggressive supportive care in the first 24 hours following surgery. Fluid administration electrolytes, and blood gas components need to be monitored, and pain relief provided until the patient is absolutely stable!
When you dog is discharged from the hospital following medical or surgical care for bloat, you will be given specific after-care instructions. These are extremely important and will be designed to help you dog heal properly and to prevent re-occurrence of the problem. Probably the most important of the instructions concern what and how to feed your dog. The most common advice is to feed a high quality (digestible) food and to soak dry kibble in water before feeding. This is necessary for the rest of your dog's life; the kibble must be soaked through before eating!

Home Remedies

How about home remedies to treat or prevent bloat? Certainly it does no harm to soak any dog's food in water before feeding, (whether or not this will affect dental health is open to debate - I don't think it matters very much.) If you do recognize the symptoms of bloat, administering medications to treat gas formation is probably okay, but be aware that any over-the-counter medications can have side effects. Also, trying to give a bloated, retching dog something by mouth can result in aspiration of the substance into the lungs. There are experienced dog breeders and handlers who have developed specific plans to deal with potential bloat situations and they can be a good source of advice experience is a valuable teacher.
If at any time you have questions concerning your dog's health, please don't hesitate to call your veterinarian. Our job is to keep your dog healthy as well as to provide care when your dog is sick.

Written by:
Dr. John J. Rutherford III, D.V.M.
Main Street Veterinary Hospital
Half Moon Bay, CA
650.726.0112

For a comprehensive list of articles and references to bloat and Canine GDV, please go to: http://www.globalspan.net/bloat.htm