A comparative study of etomidate and methohexital as induction agents for analgesic anesthesia.

Two hundred current surgical procedures were done in adult patients using neuroleptanalgesia with either methohexital (1 mg/kg) or etomidate induction (0.3 mg/kg) in half of the cases. The cardiovascular function was less altered with etomidate (less occurrence of tachycardia, blood pressure drops or systolo-diastolic pinching). The etomidate dosage chosen more often gave an immediate satisfactory sleep. However, with methohexital induction, less signs of awakening were observed during the surgical procedure. The frequent postoperative somnolence also points, although indirectly, to a longer residual effect of the barbiturate. Both drugs sometimes gave erythema. The injection of etomidate was more frequently painful in the arm. On the other hand, hiccups occurred with methohexital induction only. Etomidate induced myoclonia in one-third of the cases premedicated with diazepam and after preliminary injection of a minimal amount of fentanyl. Without these precautions, myoclonia can occur in two-thirds of the patients. However, these myoclonia are bothersome and of prolonged duration in rare instances and would be of real annoyance only when this drug would be used alone for surgical procedures of short duration where perfect patient immobility is required. We therefore conclude and confirm that etomidate is a good induction agent for neuroleptanalgesia anesthesia procedures.