Pharyngeal Paralysis In Dogs

The pharynx (upper throat) is the region where the trachea and esophagus team up behind the tongue. Malfunction in the pharyngeal region is a key pointer to an aerodigestive disorder.

The pharynx closes the respiratory tract off whenever we want to swallow food. The vocal cords firmly clamp together and at the entrance of the larynx, epiglottis drops over to divert liquid and food into the esophagus. Breathing is briefly suspended during each swallow, lasting perhaps less than a second. Once the liquid/food passes by, the breathing resumes after reopening the larynx.

The stability of the pharynx/larynx is maintained by the arytenoid cartilage on one or both sides of the larynx. When the nerves of these muscles become paralyzed or weak (paretic), the muscles become flaccid and flop into the airway resulting in pharyngeal paralysis.

Pharyngeal paralysis makes it difficult to swallow or cannot swallow. This is caused by a trauma that causes obstruction, malfunction of the pharynx, collapse, disorders in the nervous system, or other diseases in that area. In some cases, the pharynx may get affected by only one side of the throat (partial) permitting the swallowing process to happen, however, other complications may occur.

The most common form of idiopathic pharyngeal paralysis is usually seen in older, large breed dogs and has a clinical manifestation of neuromuscular disease. This is also overrepresented in brachycephalic dogs. Affected dogs are at risk of dehydration, pneumonia from ingestion of liquid and food (aspiration pneumonia), and respiratory and circulatory failure.

• Wheezing, Labored Breathing (increased effort).
• Sensitive Gag Reflex
• Gagging or Retching, particularly while swallowing.
• Dark red or purple-colored tongue.
• Excess Panting
• Inflammation of other structures in the airways.
• Ulcerated lesions with or without discharge.
• Abnormal - bark sound (dysphonia), as if the pet has laryngitis.
• Exercise Intolerance
• Voice change
• Fatigue

For mildly affected dogs: Conservative therapy is enough. Lifestyle changes like avoiding strenuous exercise and extremely warm conditions may be enough.

For overweight or obese dogs: Maintaining a healthy weight will be very important.

Anti-inflammatory medication to reduce swelling and inflammation of the pharynx are often beneficial as well.

Arytenoid Lateralization: Dogs having severe difficulty in breathing are often considered great candidates for surgery. Though there are several techniques, lateralization of the arytenoid cartilage of the larynx (laryngeal tie back) is the surgery of choice for most vets.

The drawback of this surgery is, that it exposes the larynx (as it is always open) and increases the danger of pneumonia.

Tracheotomy: Rarely this surgery is performed for the candidates that are not suitable for ‘arytenoid lateralization’. The trachea is surgically opened and a permanent tube is inserted to keep open the damaged structures.

Pay attention to a few things such as:

• The rise in temperature or summertime can cause significant dangers to their health such as heat stroke, exacerbated by dehydration.
• Provide access to 24/7 Cool Water.
• Invest in a comfy cooling pad.
• Take shorter, slower walks in the early morning or evening (during the cooler parts of the day).
• Don’t use an airway restricting collar. Use a harness instead.
• Do not leave the dogs outside for long even if you have shady areas outside.
• Weight management is really important.

Laryngeal paralysis due to the hereditary abnormality can be prevented by stopping the breeding of affected dogs so that the risk of passing the condition on to the next generation is averted.

For idiopathic causes, nobody so far knows how to completely prevent it. When you go to a breeder for a new dog or get a dog with an unknown background, ask to screen for hereditary medical conditions or do a health check prior to getting the dog.

Prevent obesity in your dog and commit to maintaining a healthy weight.

Boston Terrier, Boxer, Bouvier Des Flandres, Bull Terrier, Dalmatian, English Bulldog, English Toy Spaniel, French Bulldog, Golden Retriever, Great Pyrenees, Labrador Retriever, Newfoundland, Siberian Husky, Saint Bernard, Pekingese, Pug, Shar Pei, Shih Tzu

1. Congenital - Congenital Polyneuropathy, Brachycephalic Airway Obstructive Syndrome.
2. Acquired -

• Traumatic
• Neurological
• Neoplasia
• Polyneuropathy
• Endocrinopathy

2. Morbidity:

Some breeds are prone to congenital pharyngeal paralysis, while large breed dogs that develop in old age are said to have acquired laryngeal paralysis.

One of the main reasons pharyngeal paralysis is underdiagnosed is the signs are typically mild at first until the condition progresses, and at an advanced stage, the pet has more obvious breathing difficulties.

In warm temperatures, affected dogs are more prone to overheating and overexertion. As they cannot efficiently use panting to cool themselves, the chances of developing severe respiratory distress are high.

3. Mortality:

LP surgery has been associated with a 14 % postoperative mortality rate. However, surgical corrections of dogs reach a median survival time of 3-5 years.

4. Diagnosis:

• Examination of pharynx using an endoscope.
• Chest Radiographs
• Complete blood testing including thyroid tests.

5. Prognosis:

The aetiology determines the prognosis after surgical correction.

Traumatic causes usually have a good prognosis, whereas polyneuropathy or tumor-induced paralysis has a guarded prognosis.

The slowly progressive disease acquired idiopathic paralysis also has a good prognosis.

Contact your vet right away, if you notice any of the following:

• Respiratory gasping or distress
• Excess Panting
• Abnormal - Bark sound (dysphonia)

What to feed?

• High-quality Protein Sources: Lean boiled meats - Chicken, Beef, Turkey, or Lamb.
• Fibre Rich Foods: Apples, Pears, Oatmeal, and other foods.
• Vitamin A: Spinach, Cantaloupe, Carrots, and Beef Liver.
• Vitamin C: Red Bell Pepper, Strawberries, Kiwis, etc.

Nutrition guidelines you may like to consider:

• Low-carb dog food / Peas, Sweet Potatoes, Squash, Yams, Pumpkin, etc.
• Fresh, lean protein (Lean ground beef, White-meat skinless chicken, or turkey).
• Shrimp, Salmon, Tuna, Cod, Halibut, Trout, and Herring fish.
• Blueberries, Kale, Broccoli, Carrots.
• Iron: Lean meats like ground beef and lamb, fish, such as sardines and salmon, pumpkin, carrots, and leafy greens.
• Leafy green vegetables (lettuce, spinach, salad greens, parsley, collard greens).

The prognosis is excellent when it is diagnosed early. Typically, the dog's quality of life is improved by the surgery.

After surgery, the main obstacle to watch out for is the possibility of adverse pulmonary consequences due to aspiration pneumonia. However, the risk can be managed by the awareness of the signs and following your vet's recommendations.