Acute lung injury complicating blood transfusion in post-partum hemorrhage: incidence and risk factors

BACKGROUND: We retrospectively investigated the incidence and risk factors for\r\ntransfusion-related acute lung injury (TRALI) among patients transfused for\r\npost-partum hemorrhage (PPH).\r\nMETHODS: We identified a series of 71 consecutive patients with PPH requiring the\r\nurgent transfusion of three or more red blood cell (RBC) units, with or without\r\ntransfusion of fresh frozen plasma (FFP) and/or platelets (PLT). Clinical records\r\nwere then retrieved and examined for respiratory distress events. According to\r\nthe 2004 consensus definition, cases of new-onset hypoxemia, within 6 hours after\r\ntransfusion, with bilateral pulmonary changes, in the absence of cardiogenic\r\npulmonary edema were identified as TRALI. If an alternative risk factor for acute\r\nlung injury was present, possible TRALI was diagnosed.\r\nRESULTS: Thirteen cases of TRALI and 1 case of possible TRALI were identified\r\n(overall incidence 19.7%). At univariate analysis, patients with TRALI received\r\nhigher number of RBC, PLT and FFP units and had a longer postpartum\r\nhospitalization. Among the diseases occurring in pregnancy- and various\r\npre-existing comorbidities, only gestational hypertension and pre-eclampsia,\r\nsignificantly increased the risk to develop TRALI (p = 0.006). At multivariate\r\nanalysis including both transfusion- and patient-related risk factors,\r\npregnancy-related, hypertensive disorders were confirmed to be the only\r\npredictors for TRALI, with an odds ratio of 27.7 ( 95% CI 1.27-604.3, p=0.034).\r\nCONCLUSIONS: Patients suffering from PPH represent a high-risk population for\r\nTRALI. The patients with gestational hypertension and pre-eclampsia, not\r\nreceiving anti-hypertensive therapy, have the highest risk. Therefore, a careful \r\nmonitoring of these patients after transfusions is recommended