Bright Light Exposure in Patients Undergoing Non-cardiac Elective Surgery

What this Trial Is About

Researchers are evaluating the effects of intense light therapy on patients undergoing cardiac surgery and those critically ill in intensive care units. The study explores how bright light exposure may stabilize the Per2 protein in blood and tissue samples, potentially reducing heart muscle damage after surgery. It also investigates how light therapy might improve circadian rhythms and blood vessel function in critically ill patients to prevent complications like strokes and organ damage. Participants scheduled for primary sternotomy cardiac surgery will be randomly assigned to receive either bright light therapy or a dim placebo light for up to 10 days before surgery. The therapy involves using a bright light box for 30 minutes each morning between 8:30 and 9:00 AM. For ICU patients after trauma or elective surgery, intense light therapy or placebo light will be applied for 30 minutes each morning for 5 to 10 days. During the study, blood and buccal swabs will be collected, and a small piece of heart tissue will be taken during surgery for analysis. Noninvasive devices will monitor blood vessel function and circadian activity. Throughout participation, patients will undergo blood draws before and after light therapy, including measurements of Per2 levels, Troponin I, melatonin, triglycerides, and ANGPTL4. Endothelial function will be assessed using the Endo-PAT device, and circadian patterns will be tracked with an Actiwatch worn on the wrist. Light therapy will be supervised to ensure proper use. The study aims to understand whether light exposure can reduce heart injury during surgery and improve blood vessel function in critically ill patients, with monitoring continuing up to 10 days and beyond.

Bright Light Exposure in Surgical Patients