Role of Levobupivacaine and Fentanyl in Second Stage of Labour: An Observational Study

Abstract

Background: To achieve adequate analgesia with a possible non-significant motor block, the American Society of Anaesthesiologists (ASA) recommended using a minimal concentration of local anaesthetics for labour epidurals. However, the concentration of local anaesthetics needs to increase to achieve effective analgesia in the second stage, as more recruitment of A-δ fibre occurs. This study compared the effects of the epidural bolus of Levobupivacaine-Fentanyl and Bupivacaine- Fentanyl in the second stage of labour.
Methods: This study was carried out from April 2023 to March 2024 at the labour suit of the Department of Obstetrics and Gynaecology of Bangladesh Medical University (BMU) and Mohammadpur Fertility Services and Training Centre (MFSTC), Dhaka, under the supervision of the Department of Anaesthesia, Analgesia, and Intensive Care Medicine, BMU. Parturient requesting
labour analgesia, satisfying the inclusion criteria were randomly divided equally into Groups LF (Levobupivacaine and Fentanyl) and BF (Bupivacaine and Fentanyl). Epidural was performed at the first stage of labour (cervical dilatation ≥4 cm) and an epidural dose of 6 ml of 0.1% levobupivacaine with fentanyl 2μg/ml through the epidural catheter was administered. Degree of analgesia by VAS, motor block by Bromage scale, foetal heart rate, and blood pressure were assessed at 5, 15, and 30 minutes after epidural dosage and then hourly till delivery. At the late second stage of labour, an epidural bolus dose of 12 ml of 0.1% Bupivacaine-Fentanyl solution in group BF and 12 ml of 0.1% Levobupivacaine-Fentanyl solution in group LF was administered. After bolus, the duration of the second stage of labour, mode of delivery, and maternal satisfaction by Likert scale were measured.
Results: The study involved 44 participants who were statistically matched for age, BMI and gestational age. Pain intensity was measured by the Visual Analogue Scale (VAS), the baseline VAS scores before the bolus had a slightly lower score in the BF group (P = 0.426) and after the bolus administration, the LF group showed a significantly lower VAS score than the BF group (P = 0.001). The LF group had a notably shorter second stage (22.75±9.97) compared to the BF group (52.67±17.19) (p<0.05). Maternal satisfaction favoured LF and superior analgesic effectiveness (p<0.005).
Conclusion: The study demonstrates that epidural administration of levobupivacaine-fentanyl in the second stage achieved better analgesia, significantly shorter duration, and remarkable maternal satisfaction in comparison to bupivacaine-fentanyl.