Prophylactic vasopressin to reduce intraoperative blood loss and associated morbidities during myomectomy: A systematic review and meta-analysis of 11 controlled trials.

Objective: To collate evidence from randomized controlled trials (RCTs) and nonrandomized controlled trials (NCTs) on the efficacy and safety of vasopressin versus passive control (placebo/no treatment) during myomectomy.

Methods: Six information sources were screened until 25-June-2022. The Cochrane Collaboration tool and Newcastle-Ottawa Scale were used to evaluate the risk of bias. Data were summarized as mean difference or risk ratio with 95% confidence interval in a random-effects model.

Results: Eleven studies, comprising 1067 patients (vasopressin=567 and control=500) were analyzed. For RCTs (n = 8), the overall quality included 'high risk' (n = 4), 'low risk' (n = 2), and 'some concerns' (n = 2). For NCTs (n = 3), the overall quality included 'good' (n = 2) and 'fair' (n = 1). The mean intraoperative blood loss, mean difference in hemoglobin level, mean difference in hematocrit level, rate of perioperative blood transfusion, and mean operative time were significantly reduced in favor of the vasopressin group compared with the control group. However, there was no significant difference between both groups regarding the mean hospital stay. Pertaining to safety endpoints, after omission of an outlier study, the rate of drug-related cardiovascular adverse events did not significantly differ between both groups. There was no quantitative evidence of publication bias for the endpoint of intraoperative blood loss.

Conclusion: Among patients undergoing myomectomy, prophylactic administration of vasopressin was largely safe and correlated with significant reductions in intraoperative blood loss and associated morbidities compared with a passive control intervention. Nonetheless, the conclusions should be cautiously interpreted owing to the low-evidence quality and the used doses varied greatly between studies.