///2017 Abstract Details
2017 Abstract Details2019-08-02T15:54:53-06:00

Clonidine versus fentanyl as the adjuvant for epidural top-up for breakthrough labor pain

Abstract Number: T-21
Abstract Type: Original Research

Susan Cosgrove MD1 ; Allison Lee MD2; Ruth Landau-Cahana MD3; Thomas Lavin BS4; Stephanie Goodman MD5; Richard Smiley MD, PhD6


Epidural clonidine produces analgesia via α2-receptor agonism in the dorsal horn of the spinal cord. In conjunction with local anesthetics, it improves the quality and duration of labor epidural analgesia.1,2 Use in parturients is not widespread due to concerns for maternal hypotension, bradycardia, sedation, and fetal heart rate (FHR) abnormalities which may result with high doses (>120mcg).2 Management of breakthrough pain during labor with patient-controlled epidural analgesia (PCEA) is often provided with a top-up dose of local anesthetic and fentanyl, however, some patients experience opioid-induced side-effects. Clonidine has not been studied as an adjuvant with local anesthetic for epidural top-up to treat breakthrough labor pain. We aimed to compare analgesia and side-effects of epidural clonidine vs. fentanyl, added to bupivacaine, for breakthrough labor pain, hypothesizing equal effect.


Women with PCEA for labor (bupivacaine 0.0625% & fentanyl 2mcg/ml, infusion 12ml/hour, bolus dose 5ml, lockout 6min), requesting a top-up for breakthrough pain (VAS ≥ 5/10; 0=no pain, 10= worst pain) were randomized to Group C (n=50): 10ml bupivacaine 0.125% & clonidine 100mcg vs. Group F (n=51) 10ml bupivacaine 0.125% & fentanyl 100mcg. Pain VAS was evaluated every 5min for 15min. ‘Success’ was defined at 15min as at least a 4-point reduction in VAS. With failure of the study drug to provide adequate pain relief, the alternate study drug was given, again with 10mL 0.125% bupivacaine. With further failure at 15min, epidural lidocaine 2% 5ml was given to exclude epidural catheter failure. Maternal blood pressure (BP), heart rate (HR), degree of sedation, and FHR were recorded for 15min after each intervention; BP, HR and FHR were recorded for 2hrs after the last intervention.


Success rate was similar in both groups (Group F 38/51 vs. Group C 31/47; p = 0.38). No difference in BP (Figure) or sedation was observed; 2/51 in Group F and 1/47 in Group C received phenylephrine IV for BP sys<90 mmHg. Mild sedation occurred in 2/51 Group F vs. 7/47 Group C, and severe sedation in 1 Group F case (p=0.32) at 15 mins.


When administered with 0.125% bupivacaine 10ml, clonidine 100mcg is as effective as fentanyl 100mcg for treatment of breakthrough pain in labor. Epidural clonidine was not associated with greater hypotension, sedation or FHR abnormalities.


1 Anaesthesia 2011; 66: 769-779.

2 Anesth Analg 2002;95:728-734.

SOAP 2017