Daytime Bright Light, Circadian Abnormalities, and Delirium in Medical ICU Patients

Daytime Bright Light (DBL) will be delivered by a free-standing apparatus set to deliver 10,000 lux. The device will be placed at the bedside within 36 inches of the patient's head and is expected to provide at least 1,250 lux at the angle of gaze. To remain in the study, the patient must be in the Intensive Care Unit (ICU) through 13:00 on day 2 (e.g., the first day of potential intervention). After day 2, DBL and other study activities will continue if the patient is transferred out of the ICU to the general medical floor.

"Usual care lighting in ICU.~To remain in the study usual care patients must also remain in the MICU through 13:00 on day 2."