Propofol combined with nitrous oxide-oxygen for induction and maintenance of anaesthesia.
After a bolus of 2 mg/kg, propofol was given by continuous infusion (150 micrograms/kg/minute for 30 minutes and then 100 micrograms/kg/minute) supplemented with nitrous oxide for anaesthesia during ear surgery in 12 patients. Cardiovascular changes were not significant except for a decrease in heart rate after 60 minutes. Acid-base balance was unaffected by the amount of fatty emulsion. Cortisol levels showed a nonsignificant decrease during the prolonged administration of propofol but had recovered completely by one hour following anaesthesia. Mean blood concentrations of propofol were 10.5 micrograms/ml (SEM 1.2) at the onset of unconsciousness, between 3.4 and 4.5 micrograms/ml during continuous infusion and 2.9 micrograms/ml (SEM 0.3) on awakening. Patients opened their eyes 6 minutes (SEM 1) after discontinuation of the infusion, and were responsive at 7.5 minutes (SEM 0.5), which suggests that propofol infusion can be used safely for surgery of 2 hours' duration.
D000136:Acid-Base Equilibrium / Q000187:drug effects; D000293:Adolescent; D000328:Adult; D000768:Anesthesia, General; D000777:Anesthetics / Q000494:pharmacology; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D008297:Male; D008875:Middle Aged; D009609:Nitrous Oxide; D010100:Oxygen; D010636:Phenols / Q000097:blood / Q000494:pharmacology; D015742:Propofol
D000777:Anesthetics; D010636:Phenols; D009609:Nitrous Oxide; D010100:Oxygen; D006854:Hydrocortisone; D015742:Propofol