Perfusion techniques involve the process of delivering oxygenated blood to tissues and organs, often used in medical settings like surgeries or organ transplants. These techniques ensure that vital organs receive adequate blood flow, which is crucial for their function and survival. There are various methods of perfusion, including cardiopulmonary bypass, where a machine takes over the heart's pumping function, and extracorporeal membrane oxygenation (ECMO), which provides prolonged support for patients with severe respiratory or cardiac issues. These techniques are essential in critical care and surgical procedures to maintain tissue viability.