What is Laryngeal Paralysis?
Laryngeal paralysis is a condition that prevents opening of the larynx (opening to the tracheal airway) during breathing which results in airway obstruction and ultimately suffocation. This condition is most common in older large breed dogs (especially Labrador Retrievers) but is also seen in young dogs like Siberian Huskies. In older dogs the condition is acquired and is often associated with an underlying polyneuropathy (generalized disease of the nervous system). In young dogs, the disease is congenital, or present at birth. Unfortunately, conservative management including rest, anti-inflammatory drugs, and airway dilators are ineffective for long-term treatment of this disease. Surgery is the recommended treatment in most cases and it is associated with a good to excellent prognosis. However, significant complications can develop after surgery and the dogs caregiver must be aware of the risks prior to surgical intervention.
How is Laryngeal Paralysis Diagnosed?
Laryngeal paralysis is diagnosed by sedated upper airway examination. This procedure requires that a sedative be given to induce moderate sedation without anesthesia. A hand held laryngoscope or endoscope is then used to visualize the larynx during voluntary respiration. The diagnosis is made when the cartilages of the larynx fail to abduct (open) during inspiration. Other diagnostics that are routinely performed as part of the diagnostic work-up of dogs with suspected laryngeal paralysis include: blood tests (complete blood count, blood chemistry, and thyroid panel), urinalysis, chest radiographs (x-rays). In some cases an abdominal ultrasound, esophogram (x-rays of esophagus), and muscle/nerve biopsy may be recommended.
What does the surgical intervention involve?
Many surgical procedures have been described to treat this condition in dogs. However, the treatment most commonly performed is called unilateral cricoarytenoid lateralization but is most commonly referred to as “laryngeal tie back”. This surgery involves making a small incision over the side of the neck with subsequent dissection down to the outside edge of the cartilage of the larynx. One or two sutures are then placed to “tie back” the cartilage rim of the airway. This results in permanent opening on one side of the airway which in most cases results in significant improvement and/or resolution of the breathing difficulty. At the University of Florida, a new image-guided technique using a high-definition camera and endoscope is performed which allows the surgeon to visualize the inside of the larynx while tightening the suture. This allows the surgeon to more precisely control the amount of opening of the larynx during the surgery. This may result in more consistent clinical outcomes, and possibly, less chance of postoperative complications such as surgical failure and aspiration pneumonia. The most significant complications following a “tie back” procedure are surgical failure (4-15%) and aspiration pneumonia which may be seen in up to 24% of dogs undergoing this procedure.
Post Operative Care
While most dogs do not experience significant complications in the immediate postoperative period, your pet will require close monitoring in our intensive care unit for 1-2 days following surgery. Your pet will need to be activity restricted for 6 weeks following surgery to reduce the chance of surgical failure and to allow scar tissue to develop around the sutures. Additionally, swimming and neck collars are not recommended for the life of your dog due to the risk of airway compromise and aspiration pneumonia.