SAN FRANCISCO — Signs of fetal well-being returned more rapidly after external cephalic version in 47 women given combined spinal-epidural analgesia, compared with 48 women given systemic opioids in a randomized study.
Neuraxial analgesia has been shown in previous studies to reduce pain from external cephalic version and to improve maternal satisfaction, compared with systemic opioids, but the fetal heart rate effects of the two types of analgesia have not been compared before the current study, Dr. John T. Sullivan and associates reported in a poster presentation at the annual meeting of the American Society of Anesthesiologists.
As part of a larger study on the success of external cephalic version using different analgesia techniques, pregnant women with breech presentation were randomized to combined spinal-epidural analgesia using intrathecal bupivacaine 2.5 mg plus 15 mcg of fentanyl, or to intravenous systemic opioid analgesia using 50 mcg fentanyl. A perinatologist blinded to assignments evaluated fetal heart rate patterns for 30 minutes before and for 60 minutes after external cephalic version.
No significant differences were seen between groups in preprocedural and postprocedural baseline fetal heart rates, the degree of heart rate variability, the number of accelerations, or the number and type of decelerations, said Dr. Sullivan, associate professor of anesthesiology, Northwestern University, Chicago.
A reactive fetal heart rate after external cephalic version is a sign of fetal well-being, so investigators assessed the time to reactivity from initiation of analgesia to the development of two 15-beat accelerations (of 15 seconds duration) occurring within 20 minutes of each other.
The median time to reactivity in the combined spinal-epidural group was 13 minutes, significantly shorter than the median 39 minutes in the systemic opioid group.
One patient in each group underwent cesarean delivery immediately after external cephalic version for nonreassuring fetal heart rate patterns.
“Combined spinal-epidural analgesia for external cephalic version has no discernible deleterious impact on fetal heart rate pattern as compared with systemic opioid analgesia,” Dr. Sullivan and his associates concluded. “Furthermore, it results in a more rapid return of a reactive fetal heart rate tracing. Therefore, combined spinal epidural may provide more immediate reassurance of fetal well-being following external cephalic version.”