Effect of Green Light Exposure at Different Times on the Pain of Subjects

Résumé succinct

This study investigated the effects of green-light exposure on pain sensitivity in healthy volunteers and on perioperative pain in surgical patients. Healthy volunteers underwent 30-min green-light exposure at three different times of day (08:00-09:00, 12:00-13:00, and 16:00-17:00) on separate days using a within-subject design, with a washout period of at least 2 days between sessions. Surgical patients undergoing elective surgery under general anesthesia with preoperative arterial puncture were randomly assigned in a 1:1 ratio to either a green-light intervention group or a sham-device control group. The assigned intervention was initiated before arterial puncture and continued throughout surgery. The effects of green-light exposure on pain sensitivity, procedural pain, and perioperative pain were evaluated.