Epidural fentanyl and sufentanil for intra- and postoperative analgesia. A randomized, double-blind comparison

In a double-blind, randomized study the efficacies of concentrated fentanyl and sufentanil injections as intraoperative epidural analgesics were compared. Also, the equivalent dose of fentanyl and sufentanil administered by continuous infusion during the first 24 h postoperatively, expressed in analgesia and also considering the side-effects was determined. 53 Patients undergoing elective thoracotomy, aortic surgery and bowel surgery were randomized and treated double-blind with fentanyl 0.250 mg/ml or sufentanil 0.05 mg/ml. Preoperatively, 0.5-1 ml study medication was administered, followed by increments of 0.2-0.5 ml during surgery guided by heart rate and systolic blood pressure. Postoperatively, study medication diluted in 1.25 mg/l bupivacaine was administered by continuous epidural infusion. The infusion rate was adjusted to optimize analgesia. Dose, heart rate and systolic blood pressure were measured intra- and postoperatively. Pain, sedation, nausea and pruritus were assessed on a 10 cm visual analogue scale. There were no differences in required volume of study medication, heart rate and systolic blood pressure nor in the parameters assessed postoperatively. Administered doses were 27.5 micrograms/h fentanyl and 5.5 micrograms/h sufentanil. It was concluded that 0.250 mg/ml (0.74 mumol/ml) fentanyl is clinically equivalent to 0.050 mg/ml (0.13 mumol/ml) sufentanil.