Studies in fentanyl-supplemented anaesthesia: Awareness and effect of naloxone on early post-operative recovery

Abstract

Ninety-nine unselected patients were given a standardized general anaesthetic with fentanyl 1.5 ug-kg-' every 30 minutes and were randomly divided into three equal groups; Group I patients received naloxone 0.1 mg, Group II naloxone 0.2 mg and Group HI naloxone 0.4 mg intravenously at the end of the operation and after the reversal of neuromuscular blockade. After naloxone the level of consciousness lightened and the response to stimulus increased: the changes were significant in all three groups and the actual changes were significantly greater in Groups II and III compared with Group I. In the Recovery Room there was no significant difference among the Groups for shivering, nausea, vomiting or pain. The incidence of operative awareness was one per cent and that of dreaming eight per cent and this was unrelated to naloxone dosage. Patient acceptance was high, seven patients not wanting this type of anaesthesia again due to (a) light premedication (inherent in the study design), two patients; (b) nausea and vomiting, four patients; and (c) slow awakening, one patient. © 1981 Canadian Anesthesiologists.