To evaluate whether there are age-related differences in the plasma concentration-vs-time course of fentanyl, the authors administered fentanyl to seven infants (3-10 months), seven children (1-9 years) and seven adults (18-41 years). Anaesthesia was induced with thiopentone, nitrous oxide, and pancuronium; following tracheal intubation, fentanyl (approximately 30 micrograms X kg-1 for infants and children, 20 micrograms X kg-1 for adults) was administered as a 2-min IV infusion. Anaesthesia was maintained with nitrous oxide, pancuronium, and morphine sulphate as clinically indicated. Plasma samples were obtained for 4 h and fentanyl concentrations determined by radioimmunoassay. Plasma concentrations per microgram X kg-1 fentanyl administered were lowest in infants 4-10 and 60-240 min after the start of the 2-min infusion; values for children were lower than those for adults 4, 180 and 210 min after the start of the 2-min infusion. These findings are consistent with the authors' clinical observation that infants tolerate larger doses of fentanyl than do adults.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.