BIS Targeted Propofol Sparing Effects of Dexmedetomidine Versus Ketamine in Outpatient ERCP: A Prospective Randomised Controlled Trial

Background: Endoscopic Retrograde Cholangio Pancreatography (ERCP) is routinely performed under propofol sedation. Adjuvant drugs have improved the quality of propofol sedation while minimizing complications. The aim of the study was to compare the propofol consumption, recovery and hemodynamic profiles of dexmedetomidine versus ketamine against a placebo control with BIS targeted in the sedative range for outpatient ERCP procedures.

Materials And Methods: The study comprised of 72 patients undergoing ERCP, who were randomly allocated into one of the 3 groups: Group Dexmedetomidine (n =24) receiving a bolus and infusion of dexmedetomidine (1μg/kg and 0.5μg/kg/hr); Group Ketamine (n = 24) receiving a bolus and infusion of ketamine (0.25mg/kg and 5μg/kg/min) and Group Control (n =24) receiving saline placebo as a bolus and infusion with variable propofol boluses administered in all groups targeting BiSpectral Index between 60-70.

Results: The total propofol consumption was significantly lower in both Dexmedetomidine (162.5 ± 71.7 mg ) and Ketamine groups (158.3 ± 66.89 mg) when compared with Control group (255.83 ± 114.12 mg)(p=0.001) .Time taken (minutes) to achieve Modified Aldrette Score (MAS) >9 and Observer Assessment of Alertness and Sedation (OAAS) score >4 was significantly prolonged in Dexmedetomidine group (MAS 16.6 ± 3.18 and OAAS 16.67 ± 2.82) compared to Ketamine (MAS 10 ± 4.17 and OAAS 8.75 ± 3.68) and Control (MAS 7.5 ± 3.29 and OAAS 6.88 ± 2.47) (p<0.001). Hemodynamic profiles were comparable although patients in dexmedetomidine had a statistically significant lower heart rate (p<0.001) although without clinical significance.

Conclusion: Low dose ketamine with background propofol boluses resulted in lesser propofol consumption, with earlier recovery and favourable hemodynamics when compared with Dexmedetomidine and control group in outpatient ERCP.