Delirium screening tools in the post-anaesthetic care unit: a systematic review and meta-analysis.

Background: Delirium is a serious neurocognitive disorder among surgical patients in the post-anaesthetic care unit (PACU). Despite the development of screening tools to identify delirium, it is not clear which tool is the most accurate and reliable in assessing delirium in the PACU.

Aim: To examine the diagnostic accuracy of delirium screening tools used in the PACU.

Methods: A systematic literature search of CINAHL, MEDLINE, Embase, PsycINFO and Scopus was conducted, using MeSH terms and relevant keywords, from databases establishment to 23 April 2021. Studies were assessed for methodological quality using the Standards for Reporting of Diagnostic Accuracy Studies (STARD) tool.

Results: A total of 1503 studies were screened from the database search, four studies met the inclusion criteria for this review. Six delirium screening tools used in the PACU were identified in the selected studies. Three studies evaluated screening tools in adult surgical patients without cognitive impairment and dementia. Two studies evaluated screening tools among patients who were scheduled for elective surgery. Review results indicated that two tools, the 4A's test (4AT; sensitivity 96%; specificity 99%) and the 3 min diagnostic interview for the Confusion Assessment Method (3D-CAM; sensitivity 100%; specificity 88%), had greatest validity and reliability as a screening tool for detecting delirium in the PACU.

Conclusion: Results indicate the 4AT and the 3D-CAM are most accurate screening tools to detect delirium in the PACU. Further research is required to validate those tools among a broader surgical population, including patients with cognitive impairment, dementia and those undergoing emergency surgical procedures.