Comparison of Different Doses of Intrathecal Hyperbaric Bupivacaine in Combined Spinal Epidural Technique for Elective Caesarean Section.

SUMMARY: This double blinded prospective randomized controlled study was designed to evaluate the optimum dose of hyperbaric bupivacaine with epidural lignocaine necessary to produce adequate anaesthesia without hemodynamic instability in combined spinal epidural technique for caesarean section. Four different doses of intrathecal hyperbaric 0.5% bupivacaine (2.5mg, 5mg, 7.5mg & 10mg) were compared. The following observations were made: • Both 7.5mg and 10mg of 0.5% bupivacaine intrathecally produced adequate level of anaesthesia (T4) in most of the cases. But the occurrence of hypotension and vomiting were very high in these groups. • 2.5mg of 0.5% bupivacaine intrathecally produced a median sensory block level of T12, which required high doses of epidural supplementation of 2% lignocaine. This resulted in high occurrence of hypotension and shivering. • 5mg of 0.5% bupivacaine intrathecally produced adequate level of anaesthesia with minimal supplementation of epidural topup with 2% lignocaine. The occurrence of hypotension, vomiting and shivering were very less compared to other groups. • There was no significant difference among the groups in terms of heart rate changes, quality of surgical anaesthesia and neonatal apgar. CONCLUSION: We conclude that 5mg of 0.5% bupivacaine intrathecally with minimal epidural lignocaine can produce adequate and rapid anaesthesia for caesarean section with minimal adverse effects