Cricopharyngeal Achalasia In Dogs

Cricopharyngeal achalasia (CPA) is considered to be a neuromuscular motility disorder in which there is incomplete or asynchronous relaxation of the upper esophageal sphincter (UES) (cricopharyngeus muscle) leads to a relative inability to swallow food or liquids. This neurological abnormality is a rare condition in dogs, but it should be considered a differential diagnosis in cases of regurgitation and dysphagia.

The pharynx (upper throat) is the region where the trachea and esophagus team up behind the tongue. 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 there is achalasia or asynchrony in the esophageal sphincter (or the cricopharyngeal muscle), the muscles become flaccid and it is incapable to pass food through the muscle.

CPA makes it difficult to swallow or cannot swallow. The most common form of idiopathic CPA is usually seen in younger, 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
• Emaciation
• Regurgitation
• Bloating
• Excess panting
• Inflammation of other structures in the airways
• 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.

Thyropharyngeal And Cricopharyngeal Myotomy: surgical resectioning of the cricopharyngeus muscle is cut across or divided with the aim of breaking its grip so that it no longer obstructs the movement of food.

Botulinum Toxin: This is given to weaken the contraction of the cricopharyngeus muscle.

Pay attention to a few things such as:

• Fix a particular type of feeding schedule in place. This is one of the most important ways to lower the frequency of your dog’s regurgitation or vomiting.
• Divide 3 meals into 5-6 mini-meals and introduction of a healthy late-night snacking right before sleep to decrease the night fasting period.
• Careful with your food measurements and don’t overindulge.
• Some vets recommend feeding a little food in the morning.
• Provide access to 24/7 Cool Water.
• Don’t use an airway restricting collar. Use a harness instead.

Cricopharyngeal achalasia 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.

There is no breed disposition. Most represented breeds are Dachshund, Maltese, Springer Spaniel, Cocker Spaniel, German Shepherd, Great Dane, Golden Retriever, Greyhound, Irish Setter, Labrador Retriever, Miniature Schnauzer, Newfoundland, Wire Fox Terrier, Brachycephalic Dog Breeds

1. Causes:

Congenital: Congenital abnormalities of upper esophageal sphincter, brachycephalic airway obstructive syndrome.

Acquired:

• Traumatic
• Neuromuscular Disorders
• Neoplasia
• Endocrinopathy

2. Types:

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

3. Morbidity:

One of the main reasons the CPA is underdiagnosed is the signs are typically mild at first until the condition progresses, and at a later 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.

4. Mortality:

CPA surgery has been associated with a 10 % postoperative mortality rate. However, surgical corrections of dogs reach a median survival time of 5 years.

5. Diagnosis:

• Examination of pharynx using an endoscope
• Fluoroscopy
• Chest radiographs
• Complete blood testing including thyroid tests

6. Prognosis:

Aetiology determines the prognosis after surgical correction.

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

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

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

• Gagging or retching, particularly while swallowing
• Respiratory gasping or distress
• Excess panting

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:

• Change the food to a different texture or experiment with the food. Some animals do good with solid foods and some with liquid foods.
• Canned food can be rolled into small meatballs. The meatballs must be swallowed by the dog and this stimulates enough esophageal motility to easily pass through the esophagus.
• 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.