Programmed Intermittent Epidural Bolus Versus Continuous Infusion in Labour Analgesia

This study aims to establish if programmed intermittent epidural bolus combined to patient controlled analgesia in labour analgesia will lower the hourly bupivacaine consumption when compared to continuous infusion combined with patient controlled analgesia. The investigators' hypothesis is that the use of programmed intermittent epidural bolus will lower the hourly bupivacaine consumption.

Patients are randomised to receive either a programmed bolus of 6ml each 45 minutes or a continuous infusion of 8ml/h. In each group, they have the possibility to add a PCEA bolus of 6ml every 20min as needed.