Incidence and assessment of delirium following open cardiac surgery; A systematic review and meta-analysis.

Abstract

This systematic review and meta-analysis sought i) to provide an overview of the incidence of delirium following open cardiac surgery and ii) to investigate how incidences of delirium are associated with different assessment tools. A systematic search of studies investigating delirium following open cardiac surgery were conducted in Medline (Ovid), EMBASE, PsycINFO, CiNAHL and the Cochrane Database. Only studies with patients diagnosed or screened with a validated tool were included. Studies published from 2005 to 2021 were included in the meta-analysis.Of 7,126 individual studies retrieved, 106 met the inclusion criteria for the meta-analysis, hereof 31% of high quality. The weighted pooled incidence of delirium following open cardiac surgery across all studies was 23% (95% CI 20-26%), however we found a considerable heterogeneity (I2 = 99%), which could not be explained by subgroups or further sensitivity analyses. The most commonly applied screening tool for delirium is CAM/CAM-ICU. The lowest estimates of delirium were found by applying the Delirium Observation Scale (incidence 14%, 95% CI 8-20%), and the highest estimates in studies using "other" screening tools (Organic Brain Symptom Scale, Delirium Symptom Interview) pooled incidence of 43%, (95% CI 19 - 66%), however, only two studies applied these. Delirium following open cardiac surgery remains a complication with a high incidence of overall 23%, when applying a validated tool for screening or diagnosis. Nevertheless, this systematic review and meta-analyses highlight the significant inconsistency in current evidence regarding assessment tools and regimens. Prospero CRD42020215519.