The perfusionist works in close relation with the anesthesiologist and the surgeon. Employment as a trainee perfusionist is also required. ECMO management is commonly performed by a registered nurse, respiratory therapist, or a perfusionist. The CPB is operated by the perfusionist. Respiratory Therapists are able to fulfill the role of Perfusionist with appropriate training. The final examination for a clinical perfusionist is administered by the ANZCP over two days. During the heart operation, the perfusionist takes over the heart function. Perfusionist certifications are maintained and awarded by The American Board of Cardiovascular Perfusion.