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.

Low-dose epidural top up for emergency caesarean delivery: a randomised comparison of levobupivacaine versus lidocaine/epinephrine/fentanyl

“…15 Unlike the current study, the authors found no difference between the rate of onset or supplementation between LEF and levobupivacaine. 15 However, there are major differences between their methodology and that of the current investigation, which make comparison invalid.…”

“…15 Unlike the current study, the authors found no difference between the rate of onset or supplementation between LEF and levobupivacaine. 15 However, there are major differences between their methodology and that of the current investigation, which make comparison invalid. The patients in the earlier study had continuous infusion epidural analgesia at 10 mL/h, which delivers significantly more local anaesthetic and results in a greater degree of motor and sensory block than when midwife top ups are used.…”

“…16 The LEF top-up mixture contained only 75 lg of fentanyl. The top-up protocol used for the caesarean section gave additional local anaesthetic at 10 min if the desired block level had not been attained, 15 so the full effect of the initial top up would not be observed. The onset time was defined as block to cold at T4.…”

“…The onset time was defined as block to cold at T4. 15 A block to cold at T4 comes on faster than the block to touch and tells us nothing about the quality of the block for surgery. 11 We are given no information on the time that may have elapsed between when the T4 block was obtained and when surgery began.…”

Anaesthesia for urgent (grade 1) caesarean section

“…Extending low-dose epidural analgesia for emergency caesarean section using 0.75% ropivacaine resulted in less need for analgesic supplementation compared with 0.5% bupivacaine with similar time to reach satisfactory level of anaesthesia [12]. A comparison between 2% lignocaine with fentanyl, 0.5% levobupivacaine and 0.75% ropivacaine showed no significant difference in time to surgical readiness, defined as loss of sensation to cold at T4 between the three, but not surprisingly a longer duration of sensory block with levobupivacaine and ropivacaine [13 ]. Malhotra and Yentis [14] have examined the addition of 75 mg fentanyl to 0.5% levobupivacaine (20 ml) and did not find any benefits compared with parturients getting only 0.5% levobupivacaine.…”