Substitution of propofol for dexmedetomidine in the anaesthetic regimen does not ameliorate the post-operative cognitive decline in elderly patients

Abstract

Background and Aims: Post-operative cognitive dysfunction (POCD) is a poorly understood complication particularly observed in elderly patients, with long-term poor outcome. The randomised study was to compare the incidence of POCD in elderly with bispectral index (BIS)-guided intra-operative use of either dexmedetomidine or propofol with sevoflurane. Methods: Eighty-seven patients, planned for non-cardiac surgery under general anaesthesia, were included between June 2017 and March 2018. After exclusion of 7 patients, remaining 80 patients were randomised into dexmedetomidine group and propofol group with 40 patients each. In both the groups, BIS-guided anaesthesia was provided. Cognitive function was assessed by an anaesthesiologist using a battery of neuropsychological tests at baseline pre-operatively, third and seventh day after surgery. The data were entered into a Microsoft Excel spreadsheet and analysis was performed using Statistical Package for Social Sciences (SPSS) version 21. Results: Propofol group had a non-significant lower incidence of POCD on third day and dexmedetomidine group showed decreased incidence of POCD on seventh day, accompanied by lower anaesthetic requirement (inhalational as well as intravenous) concomitant with delayed emergence with an acceptable BIS value. Conclusion: Dexmedetomidine appeared to be anaesthetic sparing as compared to propofol. BIS monitoring for titrating depth of anaesthesia and hence the anaesthetic exposure is an invaluable tool as compared to routine care anaesthesia for reducing POCD. The patients in both groups did not develop significant POCD until the seventh post-operative day.

Keywords

• bispectral index
• dexmedetomidine
• elderly
• neuropsychological tests
• post-operative cognitive dysfunction
• propofol