Nonreassuring Fetal Heart Rate Tracings and the Dural Puncture Epidural Technique

To the Editor We read with interest the systematic review and meta-analysis by Hattler et al1 looking at the effects of combined spinal–epidural (CSE), where all trials involved the use of intrathecal opioids, versus epidural analgesia in laboring women on nonreassuring fetal heart rate (FHR) tracings. We agree that CSE analgesia is associated with a greater risk of nonreassuring FHR tracings compared with epidural analgesia. We also know from earlier studies that intrathecally administered opioid-induced uterine hypertonus, and the resulting decrease in uteroplacental perfusion, may explain the fetal bradycardia.2,3 According to a study published in 2008, dural puncture with a 25-G spinal needle without an intrathecal local anesthetic or opioid injection performed immediately before the initiation of epidural analgesia was seen to improve the sacral spread, onset, and bilateral pain relief produced in laboring nulliparous patients.4 At our institution, we have been practicing this “dry” dural puncture epidural technique in laboring patients where we pierce the dura with a 25-G spinal needle without intrathecal drug administration before initiating a low-dose epidural and have been able to avoid CSE-related abnormal FHR tracings. Because the evidence base for side effects with this technique is lacking, we are in the process of obtaining data to study the accuracy of our observations. In our opinion, this may be an interesting technique to avoid or reduce the risk of pruritus, hypotension, delayed recognition of epidural catheter failure, and/or fetal bradycardia following intrathecally administered medication. Madhumani Rupasinghe MBBS, FRCAPeter Doyle, MDDepartment of AnesthesiologyUT Health Science Center at HoustonHouston, Texas[email protected]