Background and Objectives: Intrathecal opioids potentiate the analgesic property of local anesthetics. Among an alpha2 adrenergic agonist, Clonidine potentiates the effect of local anesthetics and allows decrease in required doses. Hence, this study was conducted to evaluate effectiveness of intrathecal bupivacaine with adjuvant fentanyl and clonidine in patient undergoing lower segment caesarean section.
Material and Method: 100 participants, aged 18 to 35 years, of ASA Physical status I and II, scheduled for lower segment caesarean section under subarachnoid block, were randomly divided into two groups (n=50
each); Group C (n=50) was given intrathecal inj. Bupivacaine 0.5% heavy 1.7 ml (8.5 mg)+ inj. Clonidine 0.2 ml (30 mcg)+inj. Normal saline 0.3 ml Total volume 2.2 ml and Group F (n=50) was given intrathecal inj.
Bupivacaine 0.5% heavy 1.7 ml (8.5 mg) + inj. Fentanyl 0.5 ml (25 mcg) Total volume 2.2 ml. Degree of sensory and motor block, quality of intraoperative anesthesia, postoperative analgesia (VAS score), time of 1st rescue analgesia effective analgesia, hemodynamic variables and side effects were evaluated and compared. At VAS ≥4, rescue analgesic Inj. Diclofenac Sodium I.V. was given. Results: The result of the present study shows that in group F there was significant reduction in the time
for onset (1.20+0.36 min), peak of sensory blockade (1.99±0.59 min) and significant prolongation in the total duration of sensory blockade (240.40±53.45 min) extending into the postoperative period as compared to group C (2.02±0.45, 2.79±0.45 and 163±22.79 min respectively with p <0.0001, hence provided effective postoperative analgesia up to 12 hours. Complete analgesia lasted longer in group F for 11.46±1.9 hrs compared with group C for 10.96±1.9 min (p 0.19). The duration of effective analgesia was significantly prolonged in
group F (14.78±2.03 min) as compared with group C (13.17±1.31 min), (p<0.0001) Conclusion: In conclusion, addition of 25 μg Fentanyl as an adjuvant with 0.5% hyperbaric Bupivacaine, in subarachnoid block for lower segment caesarean section, has faster onset and prolongs sensory block and motor blockade; also improves postoperative analgesia with minimal side effects as compared to 30 μg clonidine.