Background: We designed this prospective, double-blind, randomized study to examine whether a dural puncture without intrathecal drug administration immediately before epidural drug administration would improve labor analgesia when compared to a traditional epidural technique without prior dural puncture.
Methods: Eighty nulliparous parturients with cervical dilation less than 5 cm were randomly assigned to receive a standardized epidural technique, with or without a single dural puncture with a 25-gauge (G) Whitacre spinal needle. After successful placement of the needle(s) and the epidural catheter, 12 mL of bupivacaine 2.5 mg/mL was administered through the epidural catheter and a patient-controlled epidural infusion of bupivacaine 1.25 mg/mL + fentanyl 2 mug/mL was initiated. The presence of sacral analgesia (S1) and pain scores were compared between groups.
Results: In demographically similar groups, parturients with prior dural puncture had more frequent blockade of the S1 dermatome (absolute risk difference [95% confidence interval] 22% [6-39]), more frequent visual analog scale scores <10/100 at 20 min (absolute risk difference 20% [1-38]), and reduced one-sided analgesia (absolute risk difference [95% CI] 17% [2-330]). The highest median sensory level (T10) was no different between groups.
Conclusions: Dural puncture with a 25-G spinal needle immediately before the initiation of epidural analgesia improves the sacral spread, onset, and bilateral pain relief produced by analgesic concentrations of bupivacaine with fentanyl in laboring nulliparous patients.