The influence of a bupivacaine and fentanyl epidural infusion after epidural fentanyl in patients allowed to ambulate in early labor

Epidural fentanyl after a lidocaine and epinephrine test dose provides adeq uate analgesia and allows for ambulation during early labor. This study was designed to determine the influence of an epidural infusion of bupivacaine plus fentanyl administered after initiation of epidural labor analgesia wi th fentanyl. Specifically, we evaluated whether there is an increase in mot or block or an increased time to request for further analgesic medication. Fifty-one laboring primigravid women at <5 cm cervical dilation who request ed epidural analgesia were enrolled. After a 3-mL epidural test dose of 1.5 % lidocaine with epinephrine (5 mug/mL), patients received fentanyl 100 mug via the epidural catheter. They then randomly received either an infusion (10 mL/h) of 0.0625% bupivacaine with fentanyl (3 mug/mL) or an infusion of preservative-free saline. After the administration of the initial analgesi c, pain scores and side effects were recorded for each patient at 10, 20, a nd 30 min, every 30 min thereafter, and at the time of request for addition al analgesic medication, by an observer blinded to the technique used. Ther e were no demographic differences between the two groups. The mean duration of analgesia (time from initial dose to request for additional analgesia) was increased in the group that received a continuous infusion of bupivacai ne and fentanyl compared with the Saline group (198 +/- 86 vs 145 +/- 50 mi n; P < 0.009). Side effects were similar between the two groups. No patient in either group experienced any detectable motor block. Fourteen patients chose to ambulate in the Saline group, and 12 patients chose to ambulate in the Infusion group. In early laboring patients, a continuous infusion of 0 .0625% bupivacaine infusion with fentanyl (3 mug/mL) prolonged the duration until top-up was required, after epidural fentanyl 100 mug after a lidocai ne and epinephrine test dose, and did not cause any clinically detectable m otor block.