Effect of opioid-free anesthesia on postoperative analgesia after laparoscopic gynecologic surgery

We performed this randomized controlled trial to evaluate the effect of opioid-free anesthesia (OFA) on postoperative analgesia after laparoscopic gynecologic surgery.Seventy-eight patients undergoing laparoscopic gynecologic surgery were randomized to receive either OFA (group OF) or opioid-inclusive anesthesia (group C). Postoperative sufentanil consumption within the first 24 h, Visual Analogue Scale (VAS) for pain, postoperative equivalent milligrams of morphine (EMM), severity of postoperative nausea (PN) and vomiting (PV), prevalence of postoperative nausea and vomiting (PONV), use of antiemetics, time to first passage of flatus were compared by a two-tailed Student's t-test, Wilcoxon rank-sum tests or Fisher's exact tests. Repeated measures ANOVA was used to assess the effect of allocation of groups over time.The median [IQR] sufentanil consumption within 24 h was lower in group OF (4[4.5]) than in group C (6[8], mean difference [MD]=-2, 95% confidence interval [CI] [-4 to 0], P=0.029). The VAS scores at rest and during coughing at 6 h (P=0.009 at rest; P=0.002 during coughing), VAS scores during coughing at 2 h (P=0.013) and 4 h (P=0.008), EMM (P=0.026), severities of PN (P=0.003) and PV (P=0.003), and the mean time to first passage of flatus (P=0.017) was significantly less in group OF than that in group C. The prevalence of PONV (26.3% [group OF], 68.4% [group C], OR=0.31, 95% CI [0.158 to 0.589], P<0.001), use of antiemetics (5.3% [group OF], 28.9% [group C], OR=0.136, 95% CI [0.028 to 0.667], P=0.012) was also significantly different between groups.Compared to opioid-inclusive anesthesia during laparoscopic gynecologic surgery, OFA was associated with significant improvement in postoperative analgesia, reduced PONV incidence prevalence and severity, and faster first passage of flatus.