Consequences of delirium after cardiac operations

Background: Delirium is a transient mental syndrome characterized by disturbances in consciousness, cognition, and perception. The risk that delirium will develop is increased in patients who undergo cardiac operations, especially the elderly. Generally, delirium during hospital admission is independently associated with many negative consequences, such as higher mortality, increased length of hospital stay, nursing home placement after admission, and cognitive and functional decline.

Methods: This prospective follow-up study used the Short Form 36-Item questionnaire, the Cognitive Failure Questionnaire, and a purpose-designed questionnaire to assess 300 patients who underwent elective cardiac operations at 6 months after the procedure. Postoperative delirium developed in 52 patients (17%). Mortality and readmission were also assessed.

Results: Delirium after cardiac procedures is associated with increased mortality (13.5% vs 2.0% in patients without), more hospital readmissions (45.7% vs 26.5%), and reduced quality of life. It is also associated with reduced cognitive functioning, including failures in attention, memory, perception, and motor function, and with functional dysfunction such as independency in activities of daily living and mobility.

Conclusions: Postoperative delirium after cardiac operations is associated with many important consequences. These findings provide justification for intervention studies to evaluate whether delirium prevention, early recognition, or treatment strategies might improve postoperative functional and cognitive function.