The signs of problems in the esophagus include regurgitation and swallowing difficulties. Regurgitation is when food and liquid returns before reaching the stomach. It is different to vomiting in that it has few warning signs and is effortless. The animal shows signs of nausea before vomiting and vomiting itself is an active process.
Disorders of Swallowing (Cricopharyngeal Achalasia)
The circopharyngeal muscle is the muscle that can open and close to allow food and liquid from the mouth to the esophagus. Cricopharyngeal achalasia is a condition which stops the muscle from relaxing adequately. This can cause difficulty in swallowing food and liquid. While this is usually a genetic defect, it is possible for adult dogs to develop the condition. An animal with this condition will gag and vomit when attempting to swallow. It is also possible for aspiration pneumonia to develop as a complication from this condition. This is when liquids that the animal has tried to swallow go down the trachea and into the lungs. The cause of circopharyngeal achalasia is often unknown but may bee associated with neuromuscular disorders in adult dogs. The treatment for this is usually a surgical procedure to cut the abnormal muscle. Usually the animal can swallow normally after the surgery and around seventy per cent of the surgeries are successful. If there are other neuromuscular disorders involved then the animal may be less responsive to the surgery. These animals may respond after the neuromuscular disorder is managed successfully. If aspiration pneumonia develops, it should be treated aggressively and immediately.
Expansion of the Esophagus (Megaesophagus)
Megaesophagus is when the esophagus is abnormally stretched or dilated. It can be caused by a genetic defect but can also be found in adult dogs, either in conjunction with other diseases or alone. Genetic megaesophagus is usually diagnosed soon after weaning and is hereditary in Wire-haired Fox Terriers and Miniature Schnauzers. It has also been reported in Newfoundlands, Great Danes, Irish Setters, Chinese Shar-Peis, German Shepherds, Greyhounds and cats. There are several causes for megaesophagus including lead poisoning, myasthenia gravis, systemic lupus erythematosus, polymyositis, hypoadrenocorticism, dysautonomia, nervous system disorders including cancer, and hypothyroidism. It can also occur due to injury, foreign objects present in the esophagus or compression. The main symptom is regurgitation. The animal will suddenly start to regurgitate food soon after eating, and will lose weight. There may also be respiratory problems, such as breathing difficulty and coughing. An x-ray of the chest will show food, fluid or air in the esophagus, which will be distended. Other tests may be needed to help find the cause, view the esophagus and the extent of the enlargement.
If megaesophagus is caused by another disease, it needs to be treated. It may be necessary for the animal to have surgery to correct any abnormalities in the blood vessels. While there is no specific treatment regime for megaesophagus that has no known cause, it can be managed. The dog should be fed with the upper body elevated at least forty five degrees. The dog can stand on a platform or a ramp, with the food bowl kept higher, and should remain there for at least fifteen minutes after eating. Doing this means that gravity helps the food travel down the esophagus. It is often necessary to change the texture of the food. Each dog will vary in which type of food helps prevent vomiting. Some dogs need soft gruel, others need dry food, and others may need canned food. It is usually helpful to give the food in small, frequent meals. The food should have a high calorie content so as to maintain the weight of the dog. The prognosis for an animal with this condition is guarded. Sixty per cent of animals with megaesophagus develop aspiration pneumonia, or fibrosis of the lungs, which is due to recurrent pneumonia. This can shorten the lifespan.
An esophageal stricture is a narrowing of the esophagus. This can develop after a trauma such as foreign object or caustic substance ingestion, esophageal inflammation, tumor invasion, or gastroesophageal reflux, which is when the gastric acid flows back into the esophagus. The symptoms include excessive drooling, swallowing difficulties, pain, and regurgitation. Esophageal strictures will be diagnosed by examining the esophagus using fluoroscopy or endoscopy procedures. These procedures mean that the veterinarian will see the location, number and type of strictures. Strictures are treated by stretching with a balloon catheter. This treatment has been the most successful. A balloon catheter is inserted and advanced until reaching the stricture, then the tip of the catheter is inflated. This stretches the esophagus. Other treatment methods, including surgery are not as successful as using a balloon catheter.
Inflammation in the esophagus can be caused by foreign objects or acid reflux. It can occasionally be caused by cancer, certain drugs or caustic substances. The veterinarian will perform and endoscopy to examine the esophagus. An endoscope is a flexible tube with a small camera attached at one end. The endoscope will hep the vet find foreign objects, and assess tissue damage. If the inflammation is mild, there may be no noticeable symptoms and it does not usually require any treatment. If there are noticeable symptoms, the veterinarian may prescribe drugs. If it has been caused by acid reflux, the veterinarian will prescribe drugs to reduce the stomach acid. Drugs may be prescribed to enhance the muscle tone of the lower esophagus, which will reduce the amount of escaping acid. It may be recommended for the animal to have a soft, low fat, low fiber diet which should be fed in small, frequent meals. If the inflammation is severe, it may be necessary to allow the esophagus to rest by putting a feeding tube through the wall of the abdomen. The tube will bypass the esophagus. Antibiotics may be prescribed to prevent a bacterial infection.
Foreign Objects in the Esophagus
It is more common to find foreign objects in the esophagus of a dog, than a cat. It is common to find bones, but needles, wool, rawhide pieces, fishhooks, and other objects can also become lodged. The symptoms include regurgitation, gagging, excessive and sudden drooling, and repeated attempts to swallow. Liquids may still be able to be swallowed in it is a partial obstruction, but food will not be able to be swallowed. If the obstruction is left untreated, the dog may display weight loss, appetite loss and lethargy. Foreign object can perforate the esophagus and this may need surgery. It is common for esophageal stricture to develop as a complication. It is also possible for aspiration pneumonia to occur if the regurgitated food is inhaled. The object may be visible on an x ray, although in some cases, it may be necessary to perform a contrast esophagram, a test using a dye which will show on x-rays, or an esophagoscopy, which is when the esophagus is examined with an endoscope. Any foreign object must be removed immediately. The vet may be able to remove the object with forceps or another instrument through the dog’s mouth. If this is not possible, it may be pushed into the stomach, where it will be passed along with feces, or it may be removed surgically. Surgery will be required if the object has perforated the esophagus, or the object can not be removed with the endoscope. The overall recovery rate in these cases is reported to be over ninety per cent.
Diverticula are pouch like dilations of the wall of the esophagus. They are rare in dogs, but those that are found can be genetic or acquired. If the diverticula are small there may be no symptoms. If the diverticula are large, they may trap the food which can cause breathing difficulties after eating, vomiting, or refusal to eat. The vet may use contrast x-rays to diagnose the condition. An endoscope will allow the pouch to be seen and checked for signs of ulceration and scarring. If the diverticula are small, the treatment may be a soft, bland diet with the animal eating with the upper body raised. This position should be maintained for a short time after eating. If the diverticula are large, the animal will need surgery to remove the pouch and rebuild the esophageal wall. The prognosis for recovery from the surgery is guarded to poor.