Identification of individuals at risk for postoperative cognitive dysfunction (POCD)

Abstract

Postoperative cognitive dysfunction (POCD) is common, occurring in around 10-54% of individuals within first few weeks after surgery. Although the majority of POCD is less commonly persistent later than 3 months following surgery, the condition increases length of stay (LOS), mortality and long-term cognitive decline, raising the need for a broad screening to identify individuals at risk for POCD during the perioperative period. In this narrative review, we summarize preoperative, intraoperative and postoperative risk factors for POCD reported in last 5 years and discuss neuropsychological tools and potential biomarkers and time points for assessment that might be suitable for clinical use. We aim to provide crucial information for developing a strategy of routine screening for POCD, which may assist with better identification of at-risk individuals for early interventions. Very importantly, the utilization of a standardized strategy may also allow higher consistency and comparability across different studies.

Keywords: assessment; postoperative cognitive dysfunction; risk factor; screening; tool.

Figure 1.

Flow chart of perioperative assessment for the risk of POCD and the time points for neuropsychological tests. A proposed strategy for identifying risk factors of POCD is presented in the flow chart. The risk factors could be categorized as preoperative, intraoperative and postoperative risk factors and assessed accordingly. Neuropsychological tests should be carried out at admission or 1 day before surgery, 1, 3, 5 and 7 days after surgery or at discharge. When POCD is present at time points after surgery, additional neuropsychological tests will be carried out at follow-up at 1 and 3 months, and may be carried out again during longitudinal follow-up.