title: Perioperative pharmacokinetics of transdermal fentanyl in elderly and young adult patients.
abstract: The perioperative pharmacokinetics of transdermally-delivered fentanyl were compared in 10 young adult (mean [range] age 32.7, [25-38] yr) and eight elderly (mean [range] age 73.7 [64-82] yr) patients following abdominal surgery. Transdermal fentanyl patches designed to release 50 micrograms h-1 were applied 2 h preoperatively and left in place for 72 h. Plasma fentanyl concentrations were measured by radioimmunoassay during patch application and for 30 h after patch removal. The mean half-time (time for plasma concentrations to double after patch application) was 4.2 h in the younger group and 11.1 h in the elderly group (P < 0.005). Mean maximum plasma concentrations were 1.9 ng ml-1 and 1.5 ng ml-1 in the younger and elderly groups respectively (ns). There were no differences in the time at which maximum plasma concentrations occurred (tmax), elimination half-life after patch removal, or AUC(0-infinity).
authors.affiliation: University Department of Anaesthesia, Leicester Royal Infirmary.
authors.forename: J P
authors.initials: JP
authors.lastname: Thompson
authors.forename: S
authors.initials: S
authors.lastname: Bower
authors.forename: A M
authors.initials: AM
authors.lastname: Liddle
authors.forename: D J
authors.initials: DJ
authors.lastname: Rowbotham
mesh_terms: D000005:Abdomen / Q000601:surgery; D000279:Administration, Cutaneous; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000701:Analgesics, Opioid / Q000097:blood* / Q000493:pharmacokinetics; D000768:Anesthesia, General; D005260:Female; D005283:Fentanyl / Q000097:blood* / Q000493:pharmacokinetics; D006207:Half-Life; D006801:Humans; D008297:Male; D008875:Middle Aged; D011863:Radioimmunoassay
chemical_list: D000701:Analgesics, Opioid; D005283:Fentanyl