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Item Open Access A Double-blind, Placebo-controlled Trial of Transdermal Fentanyl after Abdominal Hysterectomy Analgesic, Respiratory, and Pharmacokinetic Effects(Lippincott, Williams and Wilkins, 1994) Sandler, Alan N.; Baxter, Alan; Katz, Joel; Norman, Peter; Koren, Gideon; Roger, Sandra; Hull, Kathryn; Samson, Benoit; Friedlander, Mark; Klein, JuliaBackground: A randomized, double-blind, placebo-controlled trial was conducted to assess the analgesic, pharmacokinetic, and clinical respiratory effects of 72-h application of two transdermal fentanyl (TTSF) patch sizes in patients undergoing abdominal hysterectomy. Methods: TTSV patches releasing 50 [mu]g/h (TTSF-50) or 75 [mu]g/h (TTSF-75) fentanyl or placebo patches were applied to 120 women 2 h before abdominal hysterectomy under general anesthesia. Postoperatively, all patients had access to supplemental morphine using patient-controlled analgesia pumps. Each patient was attended continuously by a research nurse for 8 h on the night before surgery and for 84 h after patch application. The following data were collected: visual analog scale pain scores, supplementary analgesia, fentanyl plasma concentration (4-h intervals), continuous hemoglobin saturation (pulse oximetry), respiratory pattern (continuous respiratory inductive plethysmography), and adverse effects (nausea, vomiting, pruritus). Data analysis included analysis of variance, Kruskal-Wallis, and chi-squared. P < 0.05 was considered significant. Results: There were no demographic differences among groups. Visual analog scale pain scores were significantly lower for the TTSF-75 group, and supplemental morphine was significantly decreased in the TTSF-75 group in the postanesthesia care unit and for both the TTSF-50 and the TTSF-75 group for 8-48 h postoperatively. Between 5 and 36 h, the TTSF groups had significantly increased abnormal respiratory pattern including apneic episodes (tidal volume of less than 100 ml for more than 15 s) and episodes of slow respiratory rate (less than 8 breaths/min persisting for more than 5 min) and significantly increased requirement for oxygen supplementation. Nine patients in the TTSF groups were withdrawn because of severe respiratory depression compared to none in the placebo group. No significant between-group differences were present in the incidence of nausea, vomiting, or pruritus. Although fentanyl plasma concentration was higher in the TTSF-75 group than in the TTSF-50 group, the differences were not significant. Fentanyl plasma concentration decreased significantly 48 h after patch application. Conclusions: Application of TTSF patches 2 h preoperatively is associated with moderate supplementary opioid requirements for analgesia in the early postoperative period and ongoing opioid supplementation for at least 72 h. Although good analgesia is the result of this combination therapy, it is associated with a high incidence of respiratory depression requiring Intensive monitoring, oxygen supplementation, removal of the TTSF patches in approximately 11% of the patients, and opioid reversal with naloxone in approximately 8% of the patients.Item Open Access Pre-emptive lumbar epidural anaesthesia reduces postoperative pain and patient-controlled morphine consumption after lower abdominal surgery(Elsevier, 1994) Katz, Joel; Clairoux, Michel; Kavanagh, Brian P.; Roger, Sandra; Nierenberg, Hilary; Redahan, Cormac; Sandler, Alan N.The present study tested the hypothesis that patients receiving epidural bupivacaine before surgery would require less morphine postoperatively and/or report less intense pain than patients receiving epidural bupivacaine after incision but before the end of surgery. Forty-two patients (ASA class I-III) scheduled for lower abdominal surgery were randomly assigned to 1 of 2 groups of equal size and prospectively studied using a double-blind, placebo-controlled crossover design. Epidural catheters were placed in the T12-L1 or L1-L2 interspaces pre-operatively, the position of the catheter was confirmed with 3% chloroprocaine with epinephrine 1:200,000, and sensory testing was carried out until levels had receded to below T12. Group 1 received 15 ml of 0.5% epidural bupivacaine injected 35 min before incision followed by 15 ml of epidural normal saline 30 min after incision. Group 2 received 15 ml of epidural normal saline injected 37 min before incision followed by 15 ml of 0.5% epidural bupivacaine 30 min after incision. General anaesthesia was induced with thiopental (4–6 mg/kg) and maintained with N2O/O2 and isoflurane. Paralysis was achieved with pancuronium (0.1 mg/kg). Opioids were not used as pre-medication or during surgery. Postoperative analgesia consisted of patient-controlled (PCA) intravenous morphine. Visual analogue pain scores (VAS) (at rest and after standardized mobilization) did not differ significantly between the 2 groups but McGill Pain Questionnaire (MPQ) pain ratings were significantly lower in group 1 at the 24 and 72 h assessments. Group 1 used significantly less morphine than did group 2 between 12 and 24 h after surgery. Cumulative PCA morphine consumption in group 1 (55.2 ± 4.7 mg) was significantly lower than in group 2 (71.7 ± 6.1 mg) 24 h and 48 h (group 1: 86.8 ± 6.3 mg vs. group 2: 108.9 ± 9.8 mg) after surgery, but not at the 72 h assessment. Reduction in morphine dose at 24, 48 and 72 h amounted to 30%, 25% and 22%, respectively. The results suggest that single-shot pre-emptive epidural local anaesthesia is associated with a short-term morphine-sparing effect which is most pronounced between 12 and 24 h after surgery. Extending the pre-operative blockade into the postoperative period may prolong the initial advantage conferred by pre-emptive epidural local anaesthesia.