Case 15 - Laryngeal Paralysis

Answers and Discussion

Case #15 -- Laryngeal Paralysis

Answers and Discussions to the Questions:

What underlying problems can cause laryngeal paralysis?

Conditions such as neuromuscular or metabolic diseases (myasthenia gravis, hypothyroidism), trauma (bite wounds or blunt trauma to the neck), inflammation or neoplasia may lead to laryngeal paralysis. In certain breeds (Huskies, Bouvier des Flandres, English bulldogs, bull terriers), congenital laryngeal paralysis has been reported.

What emergency treatments would you do for "Chip"?

First, be certain "Chip" is not choking but do not add extra stress by aggressively examining the pharyngeal area. Start with supplemental oxygen via a mask while performing your initial assessment. "Chip's" body temperature is dangerously high. Start cooling him by spraying his body with cool water, putting cool compresses on his pads and running a fan close to him. DO NOT cool a patient with alcohol! It tends to drop the body temperature too quickly and can be dangerous if the patient were to arrest and defibrillating paddles were needed. If body temperature does not come down with these initial measures, a cold water enema can be given. The patient should be given a sedative to decrease anxiety (acepromazine 0.025 mg/kg, half IV/half SQ). An anti-inflammatory is given to decrease edema (dexamethasone sodium phosphate 0.5-1 mg/kg IV). In "Chip's" case, a tracheostomy was also needed.

Although not evident in this case, what historical complaints do you usually hear from owners of patients with laryngeal paralysis?

Owners complain their pet has become exercise intolerant. There may be an increased effort or noise associated with inspiration. The animal's voice may have changed. There may also be gagging or coughing associated with swallowing food or water.
What radiographic findings do you see?

An interstitial to alveolar pattern is seen in the left cranial and caudal lung fields. A heavy interstitial pattern is also seen in the middle and right caudal lung fields. The patient has a megaesophagus, which has probably lead to the lung changes (mild aspiration pneumonia). There is also a mild pneumomediastinum, probably caused by the tracheostomy tube placement.
What surgical technique is commonly used to treat laryngeal paralysis and what complications do you need to watch for after surgery?

A laryngeal tie-back or unilateral arytenoid lateralization surgery is performed in most cases. The most common complication is aspiration pneumonia. It is more common with bilateral tie-back surgeries than unilateral ones and should be treated with antibiotics immediately if it occurs (Baytril and Ampicillin). In this case, "Chip" already had evidence of pneumonia and was started on antibiotics.

Follow-Up: "Chip's" condition worsened over 24 hours. Surgery was delayed because of how poorly he was doing. The area around the tracheostomy site became very edematous. He arrested and attempts to resuscitate him were not successful.

Laryngeal Paralysis Pearls

Laryngeal paralysis patients present with laryngeal stridor and inspiratory distress.
Owners historically complain of exercise intolerance, a change in voice, and gagging associated with drinking.
Emergency treatments for respiratory distress due to laryngeal paralysis include oxygen supplementation, sedation, an anti-inflammatory, and possibly a tracheostomy.
Surgical fixation of the problem involves a laryngeal tie-back or unilateral arytenoid lateralization.