Clinical and Cognitive Characteristics Associated with the Onset of Delirium in Postoperative Cardiovascular Surgery Patients Admitted to the ICU.

Objectives: Occupational therapy (OT) studies of delirium have attempted to test the effectiveness of interventions to reduce the incidence and duration of delirium. Although some cognitive stimulation appears to be important, appropriate approaches to delirium characterized by cognitive dysfunction remain unclear. This study aimed to determine the incidence and duration of delirium in postoperative cardiovascular surgery patients at the initial time of OT to identify characteristics of patient demographics and cognitive function according to the presence or absence of delirium. Methods: This retrospective study included patients judged to have delirium by the Confusion Assessment Method at the first postoperative OT session (after extubation) in the intensive care unit (ICU). Patient data included age, sex, days until extubation, type of hospitalization, outcome at discharge, Sequential Organ Failure Assessment score and Glasgow Coma Scale (GCS) score at the first OT session, presence or absence of delirium, duration of delirium, and Mini-Mental State Examination-Japanese (MMSE-J) score. The Mann-Whitney U test was used to test differences between the delirium and the non-delirium groups, and a binomial generalized linear model (logistic regression model) with Bayesian estimation was adopted to investigate factors characterizing delirium. Results: A Bayesian logistic regression model with delirium as the dependent variable and "days until extubation" and "spatial orientation" as adjustment variables suggested that "spatial orientation" was a significant factor in delirium. Conclusions: For ICU patients with delirium, the provision of information tailored toward spatial orientation during the first day of OT may improve delirium.