Laryngeal Paralysis
• Other names: "Lar Par," geriatric onset laryngeal paralysis and polyneuropathy (GOLPP)
• Cause:
- The nerves of the muscles controlling the larynx become paretic or paralyzed, causing the cartilage to collapse inwards, blocking the airway.
- Most commonly this is due to an idiopathic neuromuscular disease, called "geriatric onset laryngeal paralysis and polyneuropathy (GOLPP)."
- The breeds most affected by the geriatric form are Labrador retrievers and Irish setters.
- Rarely may be secondary to trauma to the throat/neck or tumors in the neck or chest
- Endocrine diseases (ex. hypothyroidism and Cushing's disease) have also been associated with laryngeal paralysis in dogs.
- The congenital form is most common in Bouvier de Flandres, Siberian Huskies, Bull Terriers and Dalmatians.
• Species: Dogs, rarely cats
• Signs:
- usually middle aged and old, medium and large breed dogs -> owners often report patient as "slowing down" or "just getting older"
- congenital form shows clinical signs by 1 year of age
- shortage of breath
- exercise intolerance
- heat intolerance
- noisy breathing
- panting even when cool and calm
- dysphonia (hoarse or raspy)
- cough, especially with exercise, excitement, eating/drinking, or stress.
- dyspnea
- anxiety
- cyanosis, collapse, and death from asphyxiation in severe cases
• Diagnosis:
- Presumptive based on medical history, clinical signs, and diagnostic tests to rule out other causes of symptoms, such as heart disease
- Confirmation is via examination of the larynx with an endoscope or laryngoscope during voluntary respiration (requires sedation without anesthesia)
• Treatment:
- Medical management, such as anti-inflammatory drugs, antibiotics, and sedatives
- Lifestyle modifications:
avoid hot environments
avoid strenuous exercise
avoid swimming
do not use collars that will put pressure on the neck, but instead use harnesses
feed from elevated bowls
implement weight loss program
- sources were mixed as to whether mild cases can be successfully managed conservatively (with medications and lifestyle modifications alone), or if all cases eventually progress to requiring surgery or euthanasia.
- If in respiratory distress: oxygen therapy, external cooling, sedation, possibly intubation and assisted breathing
- Surgical correction is often successful at reducing or eliminating symptoms, but post-op complications such as aspiration pneumonia (up to 24% of dogs) or surgical failure (4-15%) can occur
- The most common surgical treatment is "unilateral arytenoid lateralization by tie-back" -> an incision is made through the side of the neck and the collapsed cartilage is permanently tied to the side of the larynx with suture to prevent it from creating an obstruction to breathing. [ETA: I shared a video of the surgery in a follow-up post]
- Only one side is tied back to decrease the risk of aspiration
- Recovery involves 6 weeks of post-op exercise restriction and minimizing barking
- Best performed by a boarded veterinary specialist surgeon!
•Sources:
- Video credit: Youtube user rejohnson58
- VCA Hospitals client education
https://vcahospitals.com/know-your-pet/laryngeal-paralysis-in-dogs
- American College of Veterinary Surgeons https://www.acvs.org/small-animal/laryngeal-paralysis
- University of Florida College of Veterinary Medicine Small Animal Hospital
https://smallanimal.vethospital.ufl.edu/clinical-services/surgery/soft-tissue-surgery/laryngeal-paralysis/
