Dural Puncture with a 27-Gauge Whitacre Needle as Part of a Combined Spinal-Epidural Technique Does Not Improve Labor Epidural Catheter Function

Background: This prospective, double-blind, randomized study was designed to examine whether the combined spinal-epidural technique without subarachnoid drug administration improved epidural catheter function when compared with the traditional epidural technique.

Methods: After institutional review board approval and informed consent, 251 healthy laboring parturients were randomly assigned to either group DP (combined spinal-epidural technique with 27-gauge Whitacre needle dural puncture but without subarachnoid drug administration) or group NoDP (traditional epidural technique). Patient-controlled epidural analgesia was initiated with 0.11% bupivacaine and 2 [mu]g/ml fentanyl. Top-up doses in 5-ml increments of 0.25% bupivacaine were administered if needed. Previous power analysis revealed that a sample size of 108 patients/group was needed to show a clinically useful reduction of the catheter manipulation rate from 32% to 15%.

Results: In groups DP and NoDP, 107 and 123 evaluable patients, respectively, completed the study. Demographics and outcome variables measured, including epidural catheter manipulation and replacement rate, sacral sparing, unilateral block, number of top-up doses, average hourly epidural drug usage, highest sensory blockade level, and labor analgesia quality, were not different between groups. A subgroup of 18 patients without cerebral spinal fluid return during dural puncture had a higher catheter replacement rate than those of groups DP and NoDP, but it did not reach statistical significance.