Generalisability of randomised trials of the programmed intermittent epidural bolus technique for maintenance of labour analgesia: a prospective single centre cohort study

L Gabriel; J Young; I Hoesli; T Girard; S Dell-Kuster

doi:10.1016/j.bja.2019.02.016

Generalisability of randomised trials of the programmed intermittent epidural bolus technique for maintenance of labour analgesia: a prospective single centre cohort study

Br J Anaesth. 2019 Aug;123(2):e434-e441. doi: 10.1016/j.bja.2019.02.016. Epub 2019 Mar 28.

Authors

L Gabriel¹, J Young², I Hoesli³, T Girard⁴, S Dell-Kuster⁵

Affiliations

¹ University of Basel, Basel, Switzerland.
² Basel Institute for Clinical Epidemiology and Biostatistics, University Hospital Basel, Basel, Switzerland.
³ University of Basel, Basel, Switzerland; Department of Obstetrics and Antenatal Care, University Hospital Basel, Basel, Switzerland.
⁴ University of Basel, Basel, Switzerland; Department of Anaesthesia, Surgical Intensive Care, Prehospital Emergency Medicine and Pain Therapy, University Hospital Basel, Basel, Switzerland.
⁵ University of Basel, Basel, Switzerland; Basel Institute for Clinical Epidemiology and Biostatistics, University Hospital Basel, Basel, Switzerland; Department of Anaesthesia, Surgical Intensive Care, Prehospital Emergency Medicine and Pain Therapy, University Hospital Basel, Basel, Switzerland. Electronic address: salome.dell-kuster@usb.ch.

Abstract

Background: Several randomised controlled trials show that maintenance of labour epidural analgesia with programmed intermittent epidural bolus reduces the maternal motor block compared with maintenance with a continuous infusion. However, these trials were usually restricted to healthy nulliparous parturients. To assess the generalisability of these randomised controlled trials to 'real-world' conditions, we compared maternal motor function (modified Bromage score) over time between healthy nulliparous and parous women using routinely collected quality-control data.

Methods: After ethical approval, all parturients receiving programmed intermittent epidural bolus labour analgesia between June 2013 and October 2014 were included in this prospective cohort study. Bupivacaine 0.1% with fentanyl 2 μg ml^-1 was used allowing for patient-controlled bolus every 20 min. The maternal motor function (primary outcome) was regularly assessed from insertion of the epidural catheter until delivery.

Results: Of the 839 parturients included, 553 (66%) were nulliparous and 286 (34%) were parous. The parous women had a shorter median duration of epidural analgesia (3 h 59 min vs 5 h 45 min) and a higher incidence of spontaneous delivery (66% vs 37%). The probability of being in a certain Bromage category at birth was similar in nulliparous and parous women in a general additive model adjusting for duration of epidural analgesia, number of rescue top-ups, and number of catheter manipulations (cumulative odds ratio: 1.18; 95% confidence interval: 0.98-1.41). Parous women required a higher time-weighted number and volume of rescue top-ups.

Conclusions: The results of the randomised controlled trials on a reduced motor block with programmed intermittent epidural bolus seem generalisable to parturients typically not included in these trials.

Keywords: analgesia; epidural; labour; obstetrics; patient controlled analgesia; randomised controlled trial.

Publication types

Observational Study

MeSH terms

Adolescent
Adult
Analgesia, Epidural / methods*
Analgesia, Obstetrical / methods*
Analgesia, Patient-Controlled / methods*
Anesthetics, Local / administration & dosage
Bupivacaine / administration & dosage
Cohort Studies
Female
Fentanyl / administration & dosage
Humans
Labor, Obstetric*
Middle Aged
Pregnancy
Prospective Studies
Randomized Controlled Trials as Topic / statistics & numerical data*
Young Adult

Substances

Anesthetics, Local
Fentanyl
Bupivacaine