Comparison of sedative effi cacy of epidural bupivacaine 0.5% with lignocaine 2% plus adrenaline by measuring BIS guided propofol requirement in gynaecological surgery

Abstract

Objectives: This study was conducted to compare the sedative ef! cacy of bupivacaine 0.5% with lignocaine 2% plus adrenaline in epidural anaesthesia by using BIS monitor. Study design: A randomized, double blind study. Methodology: Sixty patients, ASA physical status I or II, of age group 20-65 yrs, undergoing elective gynaecological surgery under epidural anaesthesia, were randomly but equally placed into two groups (group-B and group-L).
Patients received (2ml/segment) bupivacaine 0.5% or lignocaine 2% with adrenaline in group-B and group-L respectively, to achieve a sensory block up to T8 level. After con! rmation of sensory blockade, propofol infusion was started at a rate of 100 μg/kg/min to get a BIS value of " 80 and the time was measured (onset time). Surgery was allowed to start immediately after the onset time. Propofol infusion was titrated to maintain the BIS value at 60-80.Infusion  was stopped at the end of surgery. The time taken to reach the BIS of#90 was recorded as ‘recovery time’. The amount of propofol consumed for onset of sedation and total amount consumed during the surgery were noted and compared.Results: There was no signi! cant difference regarding demographic data and onset time in both groups (P>0.05).Recovery time was signi! cantly prolonged in group-B than group-L 5.57+1.25 min and 4.38+0.94 min respectively (P<0.05). Dose of propofol consumed for onset of sedation was signi! cantly low in group-B than group-L, 17.13+4.22 mg vs. 27.77+8.39 mg respectively (P<0.05). Total amount of propofol consumed was also signi! cantly low in group-B than group-L, 140.33+34.59 vs. 184.80+38.21 respectively (P<0.05). Conclusion: We conclude that epidural block with 0.5% bupivacaine is associated with less propofol consumption
as compared with 2% lignocaine with adrenaline to maintain BIS 60-80 and hence is more effective.