Sarns heart-lung machines, also known as cardiopulmonary bypass (CPB) machines or extracorporeal circulation machines, are essential devices used in cardiac surgery to temporarily take over the functions of the heart and lungs during open-heart procedures. These machines facilitate the circulation of oxygenated blood throughout the body while allowing the heart to be stopped for surgical interventions, such as coronary artery bypass grafting (CABG), valve replacement, or cardiac defect repair.