Oxygenator Type and Blood Cell Trauma in Cardiac Surgery

Arnrich B, Albert AA, Walter JA, Schön F, Rothe M, Ennker J. Oxygenator Type and Blood Cell Trauma in Cardiac Surgery. In: Proceedings of the 33. International Meeting of the German Society for Cardiovascular Engineering. Celle; 2004.Objective: Blood cell trauma in cardiac surgery is mainly attributed to the use of the heart lung machine and the oxygenator. The optimization of oxygenator design and membrane technology (e.g., chemical properties of surface mate rial), aiming at reducing the blood cell alterations, is an objective of current developments. Clinical evaluation of different oxygenators concerning alterations of blood cells and markers of organ function provide an appropriate level of complexity becau se various patient characteristics and operative data are involved. Our clinical research database enables us to study the impact of different oxygenator types on blood cells and markers of organ function in the homogenous group of elective coronary artery bypass grafting (CABG) patients. Materials and Methods: Prospective data from 4847 patients who underwent isolated CABG were collected, of which 282 had off - pump coronary artery bypass grafting (OPCAB). The blood cell parameters white blood cell (WBC) cou nts, platelet (PLT) counts, and red blood cell counts and the marker of organ function lactate dehydrogenase (LDH) and creatinine clearance (CC) were determined pre - and postoperatively. The changes of these parameters were analyzed among the 13 - oxygenator type groups and compared with the OPCAB group. To account for individual differences in blood volume, flow rate, and bypass time, we introduced a formula to normalize blood alterations per transfer cycle across the oxygenator. Results: We could observe si gnificant different blood cell alterations between the various oxygenator groups. The increase of WBC was positive correlated with LDH and negative with CC. The oxygenators with the least decrease in PLT had the highest WBC increase. Two manufacturer’s mod ifications in oxygenator surface material ar e observed to result in a trade - off between induced WBC and PLT blood alterations. Conclusion: Cardiotomy suction blood separation had a clear effect on blood activation parameters. The cardiotomy suction blood s eparation enabled us to separate a main part of blood activation and prevent its negative effects. Further studies should prove whether retransfusion of cardiotomy suction blood without cell saver is indicated at all in routine CABG