Dreaming associated with anaesthesia: The influence of morphine premedication and two volatile adjuvants

Abstract

An investigation is described into the problems of dreaming and recall under anaesthesia. One hundred and twenty patients were divided into four equal groups. Group 1 were anaesthetized using thiopentone for induction and nitrous oxide for the maintenance of anaesthesia, muscle relaxation being provided by tubocurarine and no premedicant or volatile anaesthetic agent being used. The three other groups received modifications of this technique: group 2 received pre-anaesthetic medication with morphine (1 mg/stone body weight (6.3 kg) 30-60 min before operation); group 3 received small concentrations (0.5-0.3 per cent) of halothane as an adjuvant, and group 4 small concentrations (0.3-0.1 per cent) of methoxyflurane. The incidence of dreaming in association with anaesthesia was high in the case of group 1 (57 per cent) but significantly less in group 2 (23 per cent; P<0.02), group 3 (0 per cent; P<0.001), and group 4 (23 per cent; P<0.02). There was no unequivocal evidence of awareness of the surgical procedure, but there were a number of dreams which appeared to be connected with the site of the operation. The significance of this is discussed. © 1971 John Sherratt and Son Ltd.