Prevention of spinal hypotension during cesarean section: A systematic review and Bayesian network meta-analysis...

The aim of this study is to perform a Bayesian network meta-analysis to evaluate the safety and efficacy of prophylactic bolus of different doses of ephedrine, phenylephrine, and norepinephrine for the prevention of spinal hypotension during cesarean section.

The Web of Science, PubMed, EMBASE, Cochrane Library were searched until to May 20, 2022. The indicators included incidence of hypotension, reactive hypertension, bradycardia, nausea and vomiting, umbilical artery pH, and Apgar scores.

About 3125 related records were obtained and 17 RCTs met our eligibility criteria. Based on the results, prophylactic bolus injection of 21-30 mg ephedrine (82%) was the best efficacious option for preventing hypotension, followed by 13-16 μg norepinephrine and 81-120 mg phenylephrine; 121-150 μg phenylephrine had the highest probability (62%) caused reactive hypertension, followed by 11-30 mg ephedrine; phenylephrine was most likely to cause bradycardia in a dose-dependent manner; 81-120 μg phenylephrine had the highest probability (37%) which associated with IONV; 6-12 μg norepinephrine (31%) had the lowest influence on IONV and had highest probability (34%) associated with improving umbilical arterial pH; 13-16 μg norepinephrine had highest probability (67% at 1 min, 49% at 5 min) which associated with improving Apgar scores.

Based on this study, 5-10 mg ephedrine and 13-16 μg norepinephrine prophylactic bolus injection may be the optimum dosage of three drugs prevent spinal-induced hypotension, which has the least impact on maternal and neonatal outcomes.