Postoperative Analgesic Effects of Three Demand-Dose Sizes of Fentanyl Administered by Patient-Controlled Analgesia

Abstract
R study, we compared the safety and efficacy of three administered demand-dose sizes of fentanyl (20, 40, and 60 [micro sign]g) in 150 patients after major surgery. Efficacy was dose-dependent; positive response rates (i.e., a global assessment score of "very good" or "excellent" and the absence of severe opioid adverse effects) were 42%, 52%, and 68% for the 20, 40, and 60 [micro sign]g demand-dose groups, respectively, and were significantly higher in the 60 [micro sign]g demand-dose group. The number of doses administered and missed attempts were significantly smaller in the 40 and 60 [micro sign]g demand-dose groups compared with the 20 [micro sign]g demand-dose group. This suggests that the 20 [micro sign]g demand dose provided inadequate pain relief. Adverse respiratory events were more frequent and mean respiratory rates were significantly slower with the 60 [micro sign]g demand dose, compared with the 20 or 40 [micro sign]g demand doses. These results indicate that, of these three doses, the 40 [micro sign]g demand dose was optimal for fentanyl PCA management of moderate to severe pain after major surgery. Implications: The postoperative analgesic efficacy of fentanyl delivered IV by patient-controlled analgesia devices has been demonstrated for demand doses ranging from 10 to 50 [micro sign]g, but the optimal fentanyl dose remains unknown. In this randomized, double-blind study, we compared three demand dose sizes of fentanyl (20, 40, and 60 [micro sign]g) and found that the 40 [micro sign]g demand dose was the most appropriate for fentanyl patient-controlled analgesia management of postoperative pain. (Anesth Analg 1998;87:890-5)...