Comparative effectiveness of intravenous remifentanil, epidural anesthesia, and a 2-step analgesic approach for external cephalic version: a large prospective single-center cohort study

BACKGROUND: Among the analgesic strategies used during external cephalic version, neuraxial anesthesia is the only approach that has consistently demonstrated higher vaginal delivery rates. However, neuraxial analgesia encompasses a heterogeneous range of techniques, and higher complication rates have been reported compared with other approaches. OBJECTIVE: This study aimed to compare the success of external cephalic version, modes of delivery, maternal pain, and complications using 3 strategies: intravenous analgesia with remifentanil, epidural anesthesia, and a stepwise approach in which epidural anesthesia was administered only if intravenous analgesia was unsuccessful. STUDY DESIGN: We conducted a single-center, consecutive 3-phase cohort study including 1963 singleton pregnancies undergoing an external cephalic version: 558 with intravenous remifentanil (Group 1, 2012-2015), 665 with intravenous remifentanil followed by epidural anesthesia 2 to 3 days later if unsuccessful (Group 2, 2016-2019), and 730 under epidural anesthesia (Group 3, 2020-2024), yielding 2218 procedures, 1233 with intravenous remifentanil and 985 with epidural anesthesia. All procedures followed a standardized protocol, performed or supervised by experienced obstetricians, with continuous presence of anesthesiologists. Ritodrine was administered for tocolysis, or atosiban when contraindicated. Outcomes included success of the external cephalic version, mode of delivery, maternal pain (0-10 numerical scale), any analgesia-related complications, and procedural-related obstetric complications including vaginal bleeding, abnormal fetal heart rate patterns, hospital admission, or any event that led to a delivery. Chi-square test was used for comparison, with significance at P