A COMPARATIVE STUDY OF INTRATHECAL HYPERBARIC BUPIVACAINE 0.5% WITH FENTANYL VERSUS HYPERBARIC BUPIVACAINE 0.5% WITH NALBUPHINE AS ADJUVANTS IN PARTURIENTS UNDERGOING ELECTIVE LSCS - A RANDOMIZED DOUBLE-BLINDED STUDY

Abstract

BACKGROUND AND AIM: Bupivacaine is the most common among the local anesthetic drugs used for spinal anaesthesia. Fentanyl is a lipophilic opioid, with a rapid onset, improving the density of subarachnoid block without producing significant side effects and improves postoperative analgesia. Nalbuphine, a mixed agonist‐antagonist opioid, has the potential to attenuate μ‐opioid effects and to enhance the kappa‐opioid effects. It produces analgesia without the undesirable side effects of a μ agonist. The aim of this study was to compare the intraoperative and postoperative analgesic effect of intrathecal fentanyl versus intrathecal nalbuphine as an adjuvant to bupivacaine during elective lower segment caesarean section (LSCS).

MATERIAL AND METHODS: Sixty parturients of American Society of Anesthesiologists (ASA) physical status I and II, aged between 20 to 35 years, scheduled for elective LSCS, were randomly allocated into two groups of 30 each. The study medication (2.5 ml of the drug solution) was prepared by the anesthesiologist who did not take part in the study. Group BF (n=30) parturient received 2.25 ml of 0.5% hyperbaric bupivacaine plus 0.25 ml fentanyl (12.5 mcg), Group BN (n=30) parturient received 2.25 ml of 0.5% hyperbaric bupivacaine with 0.25 ml nalbuphine (250 mcg). Onset time of sensory and motor block, Visual Analogue Scale (VAS) score, duration of analgesia, hemodynamic changes, and adverse effects were documented. Systolic Blood Pressure (SBP), Diastolic Blood Pressure (DBP), Mean arterial pressure (MAP) and Heart rate (HR) were recorded at varied intervals during intraoperative and postoperative period.

RESULTS: There was no pain in both groups at 1st and 2nd hours. At 5th hours after surgery VAS score were significant as p‐ value <0.05 but at 12 hours and 24 hours, it was statistically non‐significant as p‐ value > 0.05. The time to first analgesic requirement was significantly prolonged in Group BN as compared to Group BF (p < 0.001). No difference in sensory onset and motor blockage in both groups. The time to attain peak sensory level were comparable in both groups. Rescue analgesia requirement was more in group BF compared to group BN in first 24 hours. No significant changes in hemodynamics were observed.

CONCLUSION: When comparing between the two given opioids, addition of nalbuphine 250mcg to hyperbaric bupivacaine 0.5%(10mg) provide efficient and prolonged postoperative analgesia with minimum or no side effects (Pruritus, nausea, respiratory depression) than addition of fentanyl 12.5mcg to same baricity and dose of bupivacaine.