A switch comprises a rotating switch member which provides fluid communication in three modes； infusion, recirculation and priming The switch is located between the oxygenator and drug bag and the cardioplegia pump raceway. The switch has three channels molded into the rotating manifold which either direct blood and cardioplegia into the coronary arteries of the patient or into a recirculation line. When the switch is rotated into the recirculation line, a hose is in fluid connection through the switch and connects the recirculation line with the pump blood and drug inlet lines thereby allowing cooling of the cardioplegic mixture during the time between infusions.
