Endotracheal intubation without the use of muscle relaxants in patients with myasthenia gravis

Abstract

Although muscle relaxants have been widely used to facilitate endotracheal intubation, the administration of these drugs in myasthenic patients may be associated with adverse events. After obtaining Institutional Reviewing Board approval and informed, patient consent, 30 patients with myasthenia gravis were enrolled in a prospective, double-blind, randomized clinical trial. We compared intubating conditions (ease of laryngoscopy, vocal cords, cough, jaw relaxation, limb movement) following fentanyl 2 mg/kg and propofol 2 mg/kg (group PRO, n = 15) vs fentanyl 2 mg/kg and sevoflurane 5% in a 1:2 mixture of oxygen and nitrous oxide (group SEVO, n = 15). The statistical analysis was performed using Student's t test and Chi-quadrate test, p < 0.05 being regarded as significant. The overall intubating conditions were excellent in 67% of patients in the group PRO vs 80% of patients in the group SEVO (p > 0.05). One patient in each group had clinically unacceptable conditions for intubation. The mean intubation score was 5.7 +/- 1.0 in the group PRO vs 5.9 +/- 0.9 in the group SEVO (p > 0.05). Three patients receiving propofol and one patient receiving sevoflurane had mild hoarseness after the surgery (p > 0.05). Both propofol and sevoflurane, supplemented with fentanyl, provide good intubating conditions without the use of muscle relaxants in patients with myasthenia gravis.