The safety of cell saver washing all shed mediastinal blood before re-transfusing it to the patient

IntroductionCardiotomy suction blood is used in cardiopulmonary bypass (CPB) surgery to maintain blood volume in the CPB system, although it is known to contain micro emboli, cytokines and free plasma hemoglobin. Our aim was to investigate whether cell saver washing the cardiotomy suction blood before re-transfusing it is safe.MethodsThis is a retrospective study of 1671 elective coronary artery bypass patients, 209 of whom had their pericardial blood processed in a cell saver (Ce-S group). PS matching was performed with patients who had their pericardial blood returned back to the CPB-system by the cardiotomy suction (Ca-S group). Perioperative transfusion requirements, surgical outcome, postoperative lab data and mortality were then compared.ResultsThere were no differences in baseline characteristics or EuroSCORE between the groups. The number of patients requiring transfusions did not differ, but the patients in the Ca-S group received more platelets (0.34 ± 1.0 vs 0.16 ± 0.7 units, <i>p</i> = .03) than in the Ce-S group. CRP (c-reactive protein) levels at day 2 and 4 were higher in the Ca-S group (174.8 ± 67.2 and 148.9 ± 74.3 mg/L vs 160.1 ± 64.6 and 125.9 ± 67.2 mg/L, <i>p</i> = .03, <i>p</i> = .002) and so were ASAT (aspartate aminotransferase) levels (0.97 ± 0.8 vs 0.81 ± 0.6 μkat/L, <i>p</i> = .03). Mortality, postoperative ventilation time, stroke, mediastinal infections and length of stay in the ICU were the same in both groups.ConclusionsIn this retrospective study of patients undergoing elective CABG surgery, washing the cardiotomy suction blood before re-transfusion was not associated with higher risk of allogenic blood transfusion, postoperative stroke, mediastinal infections, or 30- and 365-days mortality.Clinical registration numberLU EPN 2016/4.