Cell Savers and Blood Quality

Cell savers are routinely used in our hospital during off-pump coronary artery bypass grafting to retrieve and wash blood that is lost during the operation. This washed blood is retransfused to the patient in order to prevent allogeneic blood transfusion. However, little is known about the rheologic properties and oxygen transport capacity of the washed red blood cells and the effects of retransfusion of this blood on microcirculatory blood flow and organ damage in the patient. For cell savers 3 different operating principles exist. The most common one uses discontinuous blood washing with a spinning bowl that is intermittently filled with blood, processed and emptied. A second one uses a continuous blood washing principle with a rotational disk. A third one is intermediate using features of both the discontinuous bowl technology and the continuous rotational disc technology. The investigator hypothesize that the operating principle has effects on the rheologic properties and oxygen transport capacity of the washed blood. Previous research suggested that in particular the deformability and oxygen carrier properties of the red blood cells are affected. As a consequence, red blood cells may block small blood vessels, which affects microcirculatory blood flow and tissue oxygenation. This may lead to organ damage.