Canadian Journal of Anesthesia, Vol 33, 427-432, Copyright © 1986 by Canadian Anesthesiologists' Society

Effects of Dose and Concentration of Rectal Methohexitone For Induction of Anaesthesia In Children

¹ Department of Anaesthesia and Research Institute, The Hospital for Sick Children, University of Toronto, Toronto, Ontario

Address correspondence to: Dr. Jerrold Lerman, Department of Anaesthesia, The Hospital for Sick Children, 555 University Avenue, Toronto, Ontario, M5G 1X8.

To investigate the effect of dose and concentration of rectal methohexitone for induction of anaesthesia, 60 children (ASA physical status 1 or 2) undergoing outpatient surgery were studied. Each child was randomly assigned to receive one of three rectal solutions (each containing atropine 0.02 mg·kg^-1): Group A - ten per cent methohexitone, 25 mg·kg^-1 (n = 20); Group B - ten per cent methohexitone, 15 mg·kg^-1 (n = 20);orGroupC - one per cent methohexitone, 15 mg·kg^-1 (n = 20). After induction of anaesthesia, or a maximum period of 20 minutes following rectal administration of methohexitone, halothane, nitrous oxide, and oxygen were administered by mask. The time to induction of anaesthesia, complications, postanaesthetic recovery scores, and recovery time did not differ significantly among the three groups. The incidence of failed inductions did not differ significantly between Group A (zero per cent) and Group C (ten per cent) but both were significantly less than Group B (45 per cent) (p < 0.05). Heart rate increased significantly between 10 and 30 minutes after rectal administration of methohexitone and atropine. The authors conclude that ten per cent rectal methohexitone 25 mg·kg^-1 and one per cent rectal methohexitone 15 mg·kg^-1 are equally effective for induction of anaesthesia in children and both are significantly more effective than ten per cent methohexitone 15 mg·kg^-1

Key Words: AGE: paediatrics • ANAESTHETIC: rectal atropine, rectal methohexitone