Vol.95 No.9 contentsPRACTICA OTO-RHINO-LARYNGOLOGICA
Vol. 95 No. 9 September 2002
Clinical Analysis of Recurrent Laryngeal Nerve
Paralysis following Endotracheal Intubation
Seiji Kawakita, Masamitsu Hyodo and Takahiko Yamagata
(Ehime University)
Eiji Yumoto
(Kumamoto University)
Twenty-five cases of recurrent laryngeal nerve paralysis following endotracheal intubation were clinically analyzed. The mean rate of occurrence was 1/2100 cases undergoing endotracheal intubation. Sixty-eight percent of the patients were male and the mean age was 55.6 years. There were no patients younger than 20 years old. These findings suggested that age-related decreased elasticity of the surrounding tissue of the recurrent laryngeal nerve was an important risk factor. The presumable etiology of the paralysis is disturbance of microcirculation for recurrent laryngeal nerve by endotracheal tube cuff and overlying tracheal cartilage. Nitrous oxide might diffuse into the cuffs causing a substantial increase in intracuff pressure. Vocal fold mobility was completely recovered in 88.2％ of the paralyzed vocal folds; therefore, physiological conduction block of the nerve was thought to be a pathogenesis with favorable prognosis. Number of nerve fibers distributing to the posterior cricoarytenoid muscle is relatively smaller than those of the laryngeal adductor muscles. This is a possible explanation of delayed recovery of abduction of the vocal folds.
Key words : recurrent laryngeal nerve paralysis, endotracheal intubation, physiological conduction block