Wireless wearable devices (WWD) have been shown to be an effective means to measure patient activity and sleep-wake cycles in the ICU. However, no current studies involving WWD have demonstrated the ability of these devices to measure adverse outcomes, including delirium in critically ill patients. This study is unique because the investigators will implement monitoring with the WWD prior to extubation in the ICU to correctly measure first mobilization, as well as capture quality of sleep and episodes of delirium for the first five postoperative days.

In this single-center non-randomized prospective cohort study, cardiac surgical patients undergoing cardiac surgery with cardiopulmonary bypass will be enrolled consecutively with written informed consent from the time this protocol is approved by the IRB until 100 subjects are enrolled (expected duration of subject enrollment is 12 months). Upon arrival into the ICU, cardiac surgery subjects will have a Fitbit Charge 2 device placed on their wrist and will wear the device until the fifth post-operative day. This device will wirelessly transmit data regarding activity and sleep quality to a smartphone application for the duration of wear. No identifiable patient information will be entered into the smartphone application or transmitted to any external entity.

Inclusion Criteria:

• Inclusion Criteria: Adult (Age > 18) patients undergoing scheduled, elective cardiac surgery with cardiopulmonary bypass

Exclusion Criteria:

• Those who do not meet the inclusion criteria, pregnant women, prisoners, those with skin or systemic infections, those who are paraplegic or quadriplegic and those with allergies to the polyurethane material comprising the FitBit strap.

Patients aged 18 years or older who are scheduled to undergo elective cardiac surgery at UT Southwestern Medical Center.