Abstract

Background and Aim: Epidural analgesia with local anesthetics and adjuvants, though proved to be a versatile technique in providing labor analgesia, it is associated with delayed onset of analgesia when administered in advanced stages of labor.Combined spinal-epidural analgesia (CSEA) is gaining popularity as a better neuraxiallabor analgesic technique compared to sole epidural analgesia in multiparous women as the second stage of labor rapidly progresses in this population demanding rapid analgesic onset. This combined method with low dose local anesthetic supplemented with adjuvants increases the duration of sensory blockade, augments maternal satisfaction, and minimizes side effects of local anesthetics. Although bupivacaine has been extensively used for labor analgesia, the newer enantiomer local anesthetics like levobupivacaine have become popular for intrathecallabor analgesia owing to its less cardiovascular and neurological side effects and less propensity for a motor blockade.

Therefore this study was aimed at comparing the efficacy and fetomaternal outcome profiles between bupivacaine with fentanyl and levobupivacaine with fentanyl in multiparous women.

Material and Methods: Sixty multiparous parturients in active labor, were randomly allocated into two equal groups. Group B:Received Intrathecal 1.25 mg of 0.5% Hyperbaric Bupivacaine + 25mcg Fentanyl followed by  epidural top-ups on demand using 10mlsolution containing 0.125% Bupivacaine + 2 ug/ml of Fentanyl. Group LB:receivedintrathecal 2.5mg (1ml of 0.25% isobaric levobupivacaine + 25mg fentanyl  followed by  epidural top-ups on demand using 10mlsolution containing 0.125% levobupivacaine + 2mg/ml fentanyl. Onset, duration of spinal analgesia, Mode of delivery, fetomaternal outcomes, and maternal satisfaction were assessed.

Results: Demographic and baseline variables were comparable in both the groups.Both groups had a rapid analgesic onset. Onsetin group B (n=30) was 2.96 mins(S.D=0.47) and that group LB (n=30) was 3.01 mins(S.D=0.40). This difference is not statistically significant.The mean duration of spinal analgesia in the levobupivacaine group (80.16+10.54) minutes when compared to that in the bupivacaine group (77+8.05) minutes. This difference is not statistically significant.Twenty-eightparturients in the bupivacaine group and 27 parturients in the levobupivacaine group delivered vaginally. All the neonates in both the groups had an APGAR > 7 at the end of the 5^th minute of delivery.

Two parturients in the bupivacaine group have experienced a mild motor blockade of Bromage 4, while none of the women in the levobupivacaine group had a motor block. Maternal satisfaction was excellent in both groups. Four out of thirty parturients in the bupivacaine group had transient hypotension.Two parturients in the bupivacaine group and one of the parturients in the levobupivacaine group had episodes of vomitings. Fifteenparturients in the bupivacaine group and 12 parturients in the levobupivacaine group have complained of self-limiting pruritis.

Conclusion: The newer S- enantiomer of bupivacaine is levobupivacaine which, when administered intrathecally, exhibited similar analgesic properties compared to bupivacaine with no adverse fetomaternal outcomes. Owing to its less cardiovascular and neurological side effects and better sensory block propensity at low concentrations, it can be a safe alternative to bupivacaine in the CSE technique of labor analgesia.