Transfusion and Pulmonary Morbidity After Cardiac Surgery

Background. True lung injury is among the leading causes of transfusion-related mortality. Pulmonary morbidity after cardiac surgery has been related to damaging effects of cardiopulmonary bypass and transfusion, but is confounded by cardiac-related events that may not reflect true lung injury. Thus, cardiac surgery poses unique challenges to criteria-specific diagnosis of transfusion-related acute lung injury (TRALI). Our objective was to determine the prevalence of pulmonary morbidity related to transfusion and whether TRALI consensus-criteria are applicable to cardiac surgery. Methods. A total of 16,847 patients underwent on-pump, coronary artery bypass grafting (CABG), valve, or CABG-valve surgery from September 1998 to February 1, 2006. We performed four propensity-score-matching analyses with logistic regression on probability of receiving a transfusion: total hospital red blood cell (RBC) and fresh frozen plasma (FFP) transfusion and intraoperative RBC and FFP transfusion. Outcomes included traditional cardiac-surgery-defined pulmonary morbidity and ratio of arterial partial pressure of oxygen to fractional inspired oxygen concentration (PaO2/FiO(2)), a criterion for TRALI. Results. Patients receiving RBC transfusion had more risk-adjusted pulmonary complications: respiratory distress 4.8% vs 1.5%, p < 0.001; respiratory failure 2.2% vs 0.39%, p < 0.0001; longer intubation times, 9.9 hours vs 7.5 hours, p < 0.0001; acute respiratory distress syndrome, 0.64% vs 0.21%, p = 0.015; and reintubation, 5.6% vs 1.3%, p < 0.0001. The FFP was similarly related to more pulmonary complications after surgery. By TRALI criteria, the majority manifested "lung injury" (PaO2/FiO(2) ratio < 300) but unrelated to transfusion (65% vs 64%). Conclusions. Transfusion is associated with many measures of postoperative pulmonary morbidity. Yet the PaO2/FiO(2) ratio as important criterion of TRALI is unrelated to transfusion. Thus, due to the nature of cardiac surgery, application of consensus guided diagnosis of TRALI is problematic. (Ann Thorac Surg 2009;88:1410-8) (C) 2009 by The Society of Thoracic Surgeons