Etomidate infusion. Its use in anaesthesia for general surgery

Etomidate has been studied in two groups of patients. In Group 1, 50 patients received etomidate 100 micrograms/kg/minute with fentanyl and a muscle relaxant, ventilation being with air and oxygen (50%). The technique gave a smooth, pleasant induction with all patients asleep within 2 minutes. The incidence of pain on infusion was 6% and of myoclonus 6%. Cardiovascular changes were minimal, the most common finding being persistent tachycardia. The mean recovery time was 9.1 minutes. There was no incidence of awareness, recall, or thrombophlebitis, but a 20% incidence of nausea and vomiting. In Group 2, 20 patients received the same dosage of etomidate to supplement spinal anaesthesia for lower abdominal surgery. The technique worked most satisfactorily, with patients falling quietly to sleep within 2-3 minutes with no hiccoughs, coughing or laryngospasm. Six patients exhibited myoclonus, one being severe. In no case did myoclonus interfere with the operation. The cardiovascular system remained stable in all patients. Mean recovery time was 16.1 minutes (range 3-38 minutes). Twitching and restlessness were the main complications during recovery.