Oxycodone versus fentanyl for intravenous patient-controlled analgesia after laparoscopic supracervical hysterectomy A prospective, randomized, double-blind study

Background: Oxycodone, a semisynthetic thebaine derivative opioid, is widely used for the relief of moderate to severe pain. The aim of this study was to compare the efficacy and side effects of oxycodone and fentanyl in the management of postoperative pain by intravenous patient-controlled analgesia (IV-PCA) in patients who underwent laparoscopic supracervical hysterectomy (LSH). Methods: The 127 patients were randomized to postoperative pain treatment with either oxycodone (n = 64, group O) or fentanyl group (n = 63, group F). Patients received 7.5mg oxycodone or 100 mu g fentanyl with 30-mu g ketorolac at the end of anesthesia followed by IV-PCA (potency ratio 75: 1) for 48hours postoperatively. A blinded observer assessed postoperative pain based on the numerical rating scale (NRS), infused PCA dose, patient satisfaction, sedation level, and side effects. Results: Accumulated IV-PCA consumption in group O was less (63.5 +/- 23.9mL) than in group F (85.3 +/- 2.41mL) during the first 48hours postoperatively (P = 0.012). The NRS score of group O was significantly lower than that of group F at 4 and 8hours postoperatively (P <. 001); however, the incidence of postoperative nausea and vomiting (PONV), dizziness, and drowsiness was significantly higher in group O than in group F. Patient satisfaction was lower in group O than in group F during the 48hours after surgery (P < 0.001). Conclusions: Oxycodone IV-PCA (potency ratio 1: 75) provided superior analgesia to fentanyl IV-PCA after LSH; however, the higher incidence of side effects, including PONV, dizziness, and drowsiness, suggests that the doses used in this study were not equipotent.