///2019 Abstract Details
2019 Abstract Details2019-07-13T07:45:15-05:00

Comparison of Continuous Epidural Infusion vs. Programmed Intermittent Epidural Bolus Labor Analgesia on the Incidence of Instrumented Vaginal Delivery: A Before-After Study

Abstract Number: T210-509
Abstract Type: Original Research

Daniele Parise M.D. 1 ; Elizabeth Devlin M.D.2; Stacey Burns M.D. 3; Kara Fields B.S.4; Brian T Bateman M.D., MSc5; Michaela K Farber M.D. 6

Background: Programmed intermittent epidural bolus (PIEB) is a relatively recent technique for labor analgesia that evolved from continuous epidural infusion(CEI). Compared to CEI, PIEB provides superior analgesia due to reduced hourly local anesthetic consumption, less physician intervention, and improved maternal pain and satisfaction scores (1,2). The reduced local anesthetic with PIEB may lower the incidence of motor block and need for instrumental vaginal delivery (IVD) but existing data do not consistently show this. Our institution transitioned from CEI with PCEA to PIEB with PCEA for labor analgesia on May 21, 2018 (along with a reduction in the concentration of the local anesthetic). Here we report the comparative frequency of IVD in a before-after study, along with a range of secondary outcomes that may be attributable to the approach to epidural management. We hypothesize that the PIEB group will have a lower rate of IVD.

Methods: Women who had epidural analgesia for singleton vaginal delivery at a tertiary center from March 31-May 20, 2018 (CEI group) and from May 22-July 26, 2018 (PIEB group) were evaluated. The CEI group received bupivacaine 0.125% + fentanyl 2mcg/ml; 6ml/hr infusion, PCEA bolus of 6ml every 15 minutes. The PIEB group received bupivacaine 0.0625 + fentanyl 2mcg/ml; 9 mL PIEB every 45 minutes, PCEA bolus of 10 ml every 15 minutes. Patients requiring catheter replacement, epidural bolus within 60 minutes of placement, spinal catheter and/or inadvertent dural puncture, or with a deviation in epidural dosing were excluded. The primary outcome was incidence of IVD. Secondary outcomes included the presence of motor block (defined as Modified Bromage Scale score 1-3: moderate/severe block), duration of the 2nd stage of labor, and frequency of cesarean delivery. Binary outcomes were compared between groups using multivariable logistic regression and continuous outcomes were compared between groups using multivariable linear regression.

Result: A total of 1,276 women were identified and 1,239 analyzed: 544 CEI patients (10 of 554 excluded) and 695 PIEB patients (27 of 722 excluded). Demographic and other measured characteristics were similar between groups. The rate of IVD was 43/544 (7.9%) vs. 46/695 (6.6%; adjusted OR 0.76, 95% CI 0.48-1.18, P=0.221) for CEI vs. PIEB groups, respectively. Motor block was greater in the CEI vs. PIEB group (17.1 vs 3.0%; adjusted OR 0.14, 95% CI 0.09-0.23, P<0.001). There was no difference in duration of 2nd stage of labor or rate of cesarean delivery.

Conclusions: Our unit’s transition from CEI to PIEB (along with a reduction in the concentration of the epidural mix) for labor analgesia was accompanied by a reduction in the frequency of IVD that did not reach statistical significance. There was no effect on rate of cesarean delivery in labor. We observed a markedly lower frequency of documented motor block.


1. Anesth Analg 2011:113(4); 826–31.

2. IJOA 2016:26; 32-8

SOAP 2019