A comparative study between intrathecal fentanyl and intrathecal buprenorphine as adjuvants to 0.5% hyperbaric bupivacaine in females undergoing lower segment caesarean section under spinal anesthesia: a randomized and double blinded study

Background: Double blinded study involving intrathecal hyperbaric bupivacaine (1.5 ml) with adjuvants as Fentanyl and Buprenorphine Methods: Sixty-six females posted for lower segment caesarean section under spinal anesthesia were randomized into two groups-A and B. Group A received 1.5 ml of hyperbaric Bupivacaine and 0.5 ml (75 µg) of Buprenorphine. Group B received 1.5 ml of hyperbaric Bupivacaine and 0.5 ml (25µg) of Fentanyl. Sensory blockade, motor blockade and duration of analgesia were evaluated. Randomization was done using randomization.com program with GraphPad Quick Cals. Statistical analysis was performed with Statistical Package for the Social Sciences (SPSS) statistics version 28 software. Results: There is no statistical difference in the demographic profiles of both groups. Duration of analgesia(minutes) in group A=255.37±34.63 and in group B=175.43±23.58 with p<0.001. Conclusions: A significant drop in mean arterial pressure in both groups from preoperative values throughout surgery, (p<0.05) with the exception of MAP at 50 minutes in B (p=0.139). A significant increase in heart rate at 2 and 4 minutes in group A when compared with baseline HR (p<0.05). In group B, a significant increase only at 2 minutes post spinal anesthesia, p=0.002. Forty-three patients had hypotension (28 vs. 15), p=0.008. Nausea is higher in Group A than B (26 vs. 4). The difference in sensory level of blockade is statistically insignificant, p=0.62. The difference in time of onset of motor blockade of Bromage score 1 was statistically insignificant, p=0.093. Duration of analgesia (minutes) in group A=255.37±34.63 and in group B=175.43±23.58 with p<0.001.