Fig. 3

Meta-analysis evaluating the effect of intraoperative intravenous lidocaine on a postoperative opioid consumption at PACU and postoperative pain at rest at b PACU and c 24 h after surgery. In part a, the point estimate (95% confidence interval) for the overall effect was − 4.23 (− 7.30 to − 1.15) (P = 0.007) mg intravenous morphine equivalents. In part b, the point estimate (95% confidence interval) for the overall effect on postoperative pain at PACU was − 0.05 (− 0.56 to 0.46) (P = 0.85) whereas in part c, the point estimate for the overall effect on postoperative pain at 24 h was − 0.16 (− 0.66 to 0.34) (P = 0.53) (0–10 numerical scale). The weighted mean difference for individual studies is represented by the square symbol on forest plot, with 95% CI of the differences shown as a solid line. The overall effect was estimated as a random effect