Hiatal hernias are rare in dogs. It is largely thought to be a birth defect, although in some cases trauma is considered the cause. In the case of a birth defect, it is thought to be extra elasticity in a ligament that allows excessive movement of the esophagus. English Bulldogs, Chows, French Bulldogs, Pugs and Shar Peis are the most commonly affected although, all breeds can suffer from a hiatal hernia. Males are more likely to undergo a hiatal hernia than female dogs. If dogs are going to undergo a hiatal hernia, most do so within their first year of life, in the case of inheritance. Traumatic causes can happen at any time in the life of the dog.

A hernia is defined as to when a part of the body protrudes abnormally into another part of the body. A hiatal hernia is defined as when part of a dog’s stomach and possibly esophagus is pushed out through its thoracic cavity (right near the diaphragm.)

Dogs can be asymptomatic. A visual hernia can be intermittent, pulling the tissue back into place and recurring. When seen, the bulge will be at the base of the diaphragm. As with other hernias, vomiting is common. In the case of a hiatal hernia, the dog will often vomit at times of excitement or exercise. Sometimes pneumonia develops as a complication of a hiatal hernia due to the dog vomiting and accidentally breathing food particles back into the lungs. On rare occasions, the dog may develop jaundice.

A sliding hiatal hernia is the most common of these uncommon hernias in small animals.

The reason for a hiatal hernia seems to largely be a birth defect in dogs. Trauma is sometimes to blame although not as likely. If there is a traumatic event it could also be said that dogs with a genetic predisposition are more likely to suffer. Because of the early occurrence of an inherited hiatal hernia, it should be easy to eradicate affected dogs from breeding programs.

Diagnosis will include the dog’s history (recent illnesses, injury, current medications) and clinical symptoms. Relay to the veterinary team how long your pet has been exhibiting the signs such as weight loss and regurgitation. Any other information you can pass on will aid in the diagnosis, particularly because many illnesses can have similar symptoms, for example, esophageal cancer. 

Your veterinarian will make a definitive diagnosis with x-rays. Abnormal tissue growth, lesions, and inflammation in the stomach or esophagus will help your veterinary caregiver come to a diagnosis. Because the involved tissues can intermittently slide back into a normal place, diagnosis in some canines can be difficult.

In some cases, the veterinarian may suggest an attempt to treat a hiatal hernia with medication, diet changes, and possible supplements. This will probably reduce the frequency of symptoms but may not alleviate the trouble entirely. Medications used to help relax the esophagus sphincter may be prescribed as well as common acid blockers. Feeding small, frequent low fat, low acid, high fiber meals can help. A diet comprised of highly digestible proteins and fiber is sometimes recommended. Supplements that promote tissue repair are sometimes administered. If your dog has contracted aspiration pneumonia, antibiotics may be included, as well as fluid therapy. Many pet owners opt for surgical repair after finding medication and meal management to be not enough to relieve their dog of the symptoms.

Prognosis can vary depending on which type of hiatal hernia the dog has experienced and if there are any other complications such as aspiration pneumonia. Most pet owners will see marked improvement in their pets after surgery. Some dogs will experience symptoms after surgery such as vomiting, but usually with much less frequency.