In most cardiac surgical procedures temporary interruption of the contractile activity of the heart is required in order to enable the surgeon the performance of the desired repair of the existing damage.

In such situations, blood must be stored in an external machine that practically mimics the heart and lung action.

Such machines include a pump and an oxygenation system. Blood is sent to the machine by tubing inserted to the veins draining oxygen-depleted blood into the right heart. After oxygenation, blood is returned under pressure to a great artery.