Pharmacokinetics of fentanyl during constant rate i.v. infusion for the relief of pain after surgery.
Forty-five patients in four groups undergoing orthopaedic, upper abdominal, prolonged or cardiac surgery received a constant rate i.v. infusion of fentanyl 100 micrograms h-1, for 24 h starting 2 h before surgery. A single bolus dose was given i.v. at the induction of anaesthesia. Plasma fentanyl concentrations, measured by radioimmunoassay were between 1 and 3 ng ml-1 until the infusions were discontinued. Clearance of fentanyl was decreased in the cardiac surgery group only. The elimination half-life was 7.3-9.7 h. This simple regimen produced effective analgesia.
D000328:Adult; D000368:Aged; D005283:Fentanyl / Q000008:administration & dosage / Q000097:blood* / Q000627:therapeutic use; D006207:Half-Life; D006801:Humans; D007262:Infusions, Intravenous; D007700:Kinetics; D008875:Middle Aged; D010149:Postoperative Pain / Q000188:drug therapy*; D012119:Respiration
D005283:Fentanyl