Incidence and Predictors of Post-cardiotomy Delirium

Objective: To determine the incidence and predictors of delirium after cardiac surgery.

Method: A prospective, observational study of postcardiotomy surgical patients was conducted during a 5 month period at the Minneapolis, MN, VAMC.

Results: Of the 53 patients who completed the study, 12 patients (23%) met criteria for postoperative delirium and 18 patients (34%) met criteria for postoperative subsyndromal delirium. Significant predictors of postoperative delirium included a history of cerebrovascular disease (Charlson Index item, VA CICSP), high medical comorbidity (VA morbidity risk score, Charlson Index), increased preoperative creatinine level, and an increased preoperative pain rating. When delirium and subsyndromal delirium patients were combined, a history of cerebrovascular disease, left ventricular dysfunction, or diabetes predicted the development of delirious symptoms.

Conclusions: Incident delirium occurred in 23% of patients after cardiac surgery and incident delirium symptoms, in 57%. The strongest predictor of both incident delirium and delirium symptoms was a history of cerebrovascular disease.