Induction of anesthesia using propofol in comparison with etomidate

Etomidate and propofol were compared for induction of anesthesia in a controlled study, including 24 male patients (ASA groups I and II). Following oral premedication with lormetazepam, the patients received propofol (2.5 mg kg-1; n = 12) or etomidate (0.3 mg kg-1; n = 12) over 60 s. For statistical analysis of the cardiovascular data (blood pressure and heart rate) four blocks were set up: A, baseline value including atropine dosage; B, value after induction of anesthesia; C, value after administration of halothane and vecuronium before intubation; D, value after intubation. The blood pressure fell slightly on administration of propofol while the heart rate remained nearly unchanged. Etomidate was associated with unacceptably high increases in blood pressure and heart rate. Myoclonia occurred in seven patients after etomidate and in two patients after propofol. A smoother mask ventilation was rated as a further advantage of propofol. Because of the unfavorable cardiovascular profile, the occurrence of myoclonia and poor mask ventilation, etomidate proved to be unsuitable for induction of anesthesia unless supplemented by an opioid and/or benzodiazepine. The high incidence of pain upon injection was considered to be a disadvantage of propofol.