Dewan KC, et al. - In this US nationwide cohort study of 5,718,552 cardiac surgery patients, researchers described the national population of cardiac surgery patients with opioid use disorder (OUD) and compared results with the cardiac surgery population without OUD. A significantly longer length of stay and cost significantly more per patient were evident for patients with OUD. Over the past decade, the population of patients undergoing cardiac surgery with persistent opioid use or opioid dependence has increased. Cardiac surgery is safe but associated with higher complications (the risks of blood transfusion, pulmonary embolism, mechanical ventilation, and prolonged postoperative pain) and costs in patients with OUD. Investigators recommended that patients should not be denied surgery due to OUD status, but complications should be monitored carefully after surgery.