Effect of epidural volume extension on quality of combined spinal-epidural anesthesia for cesarean delivery: A systematic review and meta-analysis

In nonobstetric procedures, epidural volume extension (EVE) has been suggested to lower intraoperative opioid requirements while improving motor recovery when added to spinal anesthesia. This systematic review with meta-analysis was performed to evaluate the efficacy of EVE in elective cesarean delivery. We searched PubMed, Embase, and The Cochrane Review Database for randomized controlled trials evaluating EVE compared with single shot spinal and/ or combined spinal/epidural anesthesia. The primary outcomes were efficacy of EVE, as defined by the need for intraoperative opioid supplementation, and time to complete motor recovery. Eighteen randomized controlled trials consisting of 1,670 patients were evaluated. Subgroup analyses of EVE with local anesthetic were statistically significant in decreasing the need for intraoperative analgesic supplementation (risk ratio = 0.30; 95% confidence interval [CI] = 0.13-0.68; P = .004; I ² = 50%). Faster motor recovery was also seen (MD -24.14; 95% CI = -47.31 to -0.98; P = .04; I ² = 98%). Sequential EVE has been affirmed as a method to decrease intraoperative opioid requirements compared with single shot spinal or combined spinal/epidural anesthesia. Improved motor recovery times were also statistically significant but should be extrapolated with caution because of high heterogeneity of the included studies.