Nine cases of vocal cord paralysis following the endotracheal anesthesia for cases of abdominal operation were reported.
Results of the electromyographic examination of the intrinsic laryngeal muscles and free movability of the cricoarytenoid joints assured by manipulating laryngeal spatula (5cases out of the nine) revealed that injury of the recurrent laryngeal nerve was responsible for the disturbance of movement of the vocal cord.
Statistical observation of the reported cases of recurrent laryngeal nerve paralysis associated with endotracheal anesthesia in our country, including author's, revealed :(a) paralysis occured more frequently in the cases above 40 years old, (b) the paralysed vocal cords were often fixed in the intermediate position at the first inspection, (c) many cases had no laryngitis, (d) the prognosis was relatively good and healed within 3 months after operation.
Some factors of nerve injury such as overextension of the neck during intubation and operation, pressure on the nerve by unsuitable endotracheal tube and cuff that was over-expanded, decrease in elasticity of the trachea and surrounding tissues, vulnerability and anatomy of the nerve, influence of muscle relaxants were deemed to be possible causes, and authors considered the interaction by their combination responsible for the nerve injury.
For the purpose of investigation of vocal cord paralysis complicated with endotracheal anesthesia, the necessity of the examination at the early stadium after operation and each professional reseach were emphasized.
