Comparison of 2% lignocaine with adrenaline and fentanyl, 0.75% ropivacaine and 0.5% levobupivacaine for extension of epidural analgesia for urgent caesarean section after low dose epidural infusion during labour

Abstract

Low dose local anaesthetic and fentanyl epidural solutions are commonly 'topped-up' for urgent caesarean section. However, the block characteristics associated with newer local anaesthetics such as ropivacaine 0.75% and levobupivacaine 0.5% have not been fully determined. In a randomised double-blinded controlled clinical trial, we compared 2% lignocaine with adrenaline and fentanyl (LAF), 0.75% ropivacaine and 0.5% levobupivacaine for extension of low dose epidural analgesia for urgent caesarean section in 90 Asian parturients. There was no significant difference in the median, interquartile range, time to T4 loss of sensation to cold between LAF (9.5, 7.0 to 13.3 minutes), 0.75% ropivacaine (10.0, 7.0 to 15.0 minutes) and 0.5% levobupivacaine (10.0, 7.0 to 15.0 minutes). No woman required conversion to general anaesthesia. The supplementation rate did not differ between groups. Levobupivacaine provided a longer duration of sensory block compared to LAF but a similar duration to 0.75% ropivacaine. Under the conditions of this study there was no significant difference in time to surgical readiness (defined as loss of sensation to cold to T4) between LAF, 0.75% ropivacaine and 0.5% levobupivacaine groups. Ropivacaine and levobupivacaine are suitable alternatives for extending epidural analgesia for urgent caesarean section.