Post-operative intravenous patient-controlled analgesic efficacy of morphine with ketorolac versus nefopam after laparoscopic gynecologic surgery: a randomized non-inferiority trial

BACKGROUND Nefopam is a non-opioid non-steroidal centrally acting analgesic. This study was conducted to assess the analgesic efficacy of intravenous patient-controlled analgesia (IV-PCA) using nefopam alone, compared with a combination of morphine and ketorolac, after laparoscopic gynecologic surgery. METHODS Sixty patients undergoing laparoscopic gynecologic surgery received IV-PCA. Group A (n = 30) received IV-PCA with a combination of morphine 60 mg and ketorolac 180 mg, while group B (n = 30) received nefopam 200 mg (basal rate 1 ml/h, bolus 1 ml, and lockout time 15 min for both). The primary outcome evaluated was analgesic efficacy using the visual analogue scale (VAS). Other evaluated outcomes included the incidence rate of postoperative nausea and vomiting (PONV), patient satisfaction of pain control, percentage of patients requiring additional opioids, and incidence rate of postoperative adverse effects. RESULTS Group B was not inferior to group A in relation to the VAS in the post-anesthesia care unit, and at 12, 24, and 48 h after surgery (mean difference [95% confidence interval], 0.50 [-0.43 to 1.43], -0.30 [-1.25 to 0.65], -0.05 [-0.65 to 0.55], and 0.10 [-0.55 to 0.75], respectively). The incidence rate of nausea was lower in group B than in group A at 12 and 24 h after surgery (P = 0.004 and P = 0.017, respectively). There were no significant differences in the other outcomes between groups. CONCLUSIONS IV-PCA using nefopam alone has a non-inferior analgesic efficacy and produces a lower incidence of PONV in comparison with IV-PCA using a combination of morphine and ketorolac after laparoscopic gynecologic surgery.