Introduction: 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.
Material and methods: 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.
Results: 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).
Conclusion: Both propofol and sevoflurane, supplemented with fentanyl, provide good intubating conditions without the use of muscle relaxants in patients with myasthenia gravis.