Postoperative cognitive dysfunction and dementia: what we need to know and do

Abstract

Approximately 12% of apparently previously cognitively well patients undergoing anaesthesia and noncardiac surgery will develop symptoms of cognitive dysfunction after their procedure. Recent articles in this Journal have highlighted the difficulties of confirming any clear links between anaesthesia and cognitive dysfunction, in part because of the lack of consistency regarding definition and diagnosis. Postoperative cognitive dysfunction (POCD) is usually self-limiting and rarely persists in the longer term, although plausible biological mechanisms for an impact on brain protein deposition do exist. Clinical research studies are frequently confounded by a lack of agreed definitions and consistency of testing. Preoperative assessment of neurocognitive function and risk factor identification is imperative in order to ascertain the true extent of POCD and any causative link to anaesthesia and surgery. At present a multidisciplinary care bundle approach to risk factor stratification and reduction is the most attractive management plan based on evidence of slight benefit from individual interventions. As yet no individual anaesthetic technique, drug or mode of monitoring has been proved to reduce the incidence of POCD. Providing patients with appropriate and accurate information can be difficult because of conflicting evidence. The Royal College of Anaesthetists' patient liaison group has produced a useful patient information leaflet that is designed to provide guidance in discussions of individual risks whilst considerable uncertainties remain.

Validation of the cognitive recovery assessments with the Postoperative Quality of Recovery Scale in patients with low‐baseline cognition

“…Recovery improved over time in both normal and low‐baseline groups in a manner that is consistent with previous data , indicating that the new scoring system produces similar results in low‐baseline participants to the normal baseline participants. This similarity of cognitive recovery between groups that have normal vs. low‐baseline cognition has potentially important clinical implications given the current debate regarding the relationship between pre‐existing cognitive impairment and poor postoperative cognitive function , and emphasises the need to validate a scoring system with which to measure cognitive recovery in those patients with a low pre‐operative baseline.…”

Peri‐operative optimisation of elderly and frail patients: a narrative review

“…Pre‐operatively, any pre‐existing cognitive impairment or dementia should be documented. For high‐risk cases, thorough discussion with, and counselling of, patients and families of the possibilities of cognitive change is highly recommended . Benzodiazepines must be avoided if possible.…”

Guidelines for the peri‐operative care of people with dementia

“…Proactive multicomponent interventions (such as Hospital Elder Life Program (HELP http://www.hospitalelderlifeprogram.org) are currently the most effective form of managing POD , reducing its incidence, duration and severity in various surgical populations . Such interventions involve standardised pathways for diagnosing and monitoring factors known to impair cognition after surgery and anaesthesia and treating these using both non‐pharmacological and pharmacological methods.…”