Although the actual benefits of walking during labor are unproven, many women express the desire to walk during labor. Combined spinal–epidural analgesia performed with intrathecal opioids has gained acceptance in this application because it causes minimal motor block. Cohen et al. designed a randomized, double-blind study to evaluate analgesic effectiveness and ability to walk after receiving a bolus of either 0.0625% bupivacaine or 0.125% bupivacaine (with sufentanil), with or without previous administration of the traditional lidocaine–epinephrine test dose.
Sixty healthy women in active labor, all of whom requested epidural analgesia and who expressed a desire to walk during labor, participated in the study. Visual analog pain scores were 3 or more, and cervical dilation was between 1 and 6 cm for participants. All subjects received a 3-ml epidural injection (a 1.5% lidocaine–epinephrine test dose or bupivacaine) and 3 min later, 12 ml bupivacaine with 10 μg sufentanil injected in two increments 3 min apart. Maternal blood pressure and visual analog pain scores were recorded before study drug administration and after completion of the bolus injections at 5, 10, 15, 20, 30, and 60 min, and then hourly for 4 h until delivery. Data relating to ambulation, balance, proprioception, and motor block were collected at baseline, 30 min, 1 h, and then hourly until delivery. Ability to walk with little or minimal assistance across the room was rated as either “yes” or “no.” Women who walked spent approximately 5–10 min out of bed and usually attempted to void, and then were reassessed for balance, among others.
A high percentage of women in all groups (75–93%) walked at some stage during labor. The group receiving the bolus of 0.125% bupivacaine with sufentanil, without a previous test dose, experienced the best analgesia and walked earlier than women in all other groups. Fewer women walked within 1 h of block placement when they received a test dose before 0.125% bupivacaine. With or without a test dose, 0.0625% bupivacaine with sufentanil provided inadequate analgesia. Women in the two latter groups required additional bupivacaine, which in turn impaired their ability to walk. The authors suggest that, based on these results, walking during the early postblock period would be possible by omitting the lidocaine–epinephrine test dose and using 0.125% bupivacaine for the initial bolus.