Background: This randomized study was conducted to compare the synergistic effect of intrathecally administered fentanyl and hyperbaric bupivacaine on hemodynamic, sensory and motor block characteristics alongwith their side effects.

Context: This randomized study was done on pregnant women undergoing caesarean section under spinal anaesthesia.

Aims: To compare and determine the efficacy of spinal anaesthesia with bupivacaine alone and in combination of different low doses of bupivacaine with additive fentanyl.

Settings and Design: This study included 75 pregnant women scheduled for caesarean section who were then randomized into three groups of twenty five each. Group 1 (B group) received 12.5 mg (2.5 ml) of 0.5% of hyperbaric bupivacaine intrathecally, Group 2 (BF1 group) received 10 mg (2 ml) of 0.5% of hyperbaric bupivacaine + 12.5µg (0.5ml) fentanyl intrathecally, Group 3 (BF2group) received 8 mg (1.6ml of 0.5%) of hyperbaric bupivacaine + 12.5µg (0.5ml) fentanyl + 0.4 ml normal saline intrathecally.

Statistical analysis used: The data of the study were recorded in the record chart and results were evaluated using statistical tests (ANOVA, student t-test, chi-square test and post hoc test, F-test whichever was applicable. 

Results: Onset of sensory block to T10 dermatome occurred faster with increasing bupivacaine doses. Onset of motor block and duration of motor block was also longer in group B as compared to BF1 and BF2. The addition of Fentanyl to Bupivacaine significantly delayed the postoperative pain and sensory recovery.

Conclusions: Spinal anaesthesia for cesarean delivery using low dose hyperbaric bupivacaine in combination with fentanyl is associated with significantly less hypotension, vasopressor requirement and nausea.