HIATUS HERNIA IN DOGS

Your dog was diagnosed with a hiatus hernia? What exactly is it? How does it manifest itself and how is it treated?

What is a hiatus hernia?

A hiatus hernia occurs when the upper part of the stomach, called the cardia, passes through the natural opening of the diaphragm called the esophageal hiatus. In a hiatus hernia, part of the stomach is in the chest cavity instead of the abdominal cavity.

There are several types of hiatus hernia and they can be distinguished as follows:

Type 1 hiatus hernia in which the junction between the esophagus and stomach and part of the stomach slides through the esophageal hiatus. This is the most common type of hiatus hernia.

Type 2 hiatal hernia or paraesophageal hiatal hernia where only the fundus of the stomach (upper stomach) or another abdominal viscera passes through the diaphragm without displacement of the junction between the esophagus and the stomach which remains in the abdominal cavity.

Hiatus hernia type 3 when type 1 and type 2 hernias are associated.
The hiatus hernia of type 4 which is a type 3 hernia complicated by the passage of other organs through the natural orifice of the diaphragm.

What causes hiatal hernia in dogs?

In some cases, hiatal hernia is a congenital anomaly, present from birth. And, although all breeds of dogs can be affected, some breeds of dogs seem to be predisposed to it. This is notably the case for brachycephalic breeds such as the Shar Pei, English Bulldog, French Bulldog, Chow Chow, Boston Terrier and Pug.

Hiatal hernias can also be acquired as a result of chest or abdominal trauma or during the obstructive respiratory syndrome that affects brachycephalic breeds.

What are the symptoms of a hiatus hernia?

The most common symptoms associated with hiatal hernias are vomiting and excessive salivation (or ptyalism). Affected dogs may also experience regurgitation, coughing, anorexia, weight loss and breathing difficulties often associated with false-swallow pneumonia.

When hiatus hernia is congenital, symptoms appear before the age of one year and can even sometimes coincide with weaning, around 2 months of the dog’s life.

How is a hiatus hernia diagnosed?

Diagnosis is based on medical history, clinical signs and chest X-rays. Most dogs require an X-ray with preparation that involves the ingestion of baryte to reveal the hernia. Esophagogastric endoscopy may also be performed.

How is a hiatus hernia treated?

A conservative medical treatment will generally be prescribed for dogs that do not require surgical treatment.
This medical treatment is based on :

anti-secretory drugs and proton pump inhibitors to control esophagitis and gastroesophageal reflux.
antiemetics to calm vomiting,
a special low-fat diet to promote gastric emptying.

Antibiotics are used as needed to fight any secondary infection, especially if aspiration pneumonia develops.

In severe or chronic cases that do not respond well to medical treatment, surgery is recommended. The techniques then vary according to the type of hiatus hernia. In brachycephalic dogs, it is usually necessary to surgically correct the respiratory disorders before intervening on the hiatus hernia.