Determination of acute lung injury after repeated platelet transfusions

Acute lung injury (ALI) during hematopoietic stem cell transplant (HSCT) is associated with substantial morbidity; however, the frequency of ALI in HSCT patients is poorly characterized. Platelets are postulated to play a critical role in the pathogenesis of ALI. Using a transfusion trial of pathogen inactivated platelet components (PC-Test) compared with conventional PC (Reference) populated with HSCT patients, data were reviewed by an adjudication panel to determine the frequency of ALI overall, by treatment groups, and key outcomes: PC exposure, ventilator-free days, and mortality. The diagnosis of ALI was based on American European Consensus Criteria. Of 645 patients who received PC over 28 days, 100 (15.5%) had clinically serious pulmonary adverse events, and 35 (5.4%) met criteria for ALI. Days of platelet support and number of platelet transfusions for patients with ALI were not significantly different from patients without ALI (P > .05). Mortality was greater for patients with ALI (57%) than those without (17%, P < .001) but not significantly different between treatment groups. For patients with ALI, the distributions of time to onset of mechanical ventilation were significantly different (P = .04). Patients supported with Reference PC were more likely to be ventilated sooner than patients receiving Test PC.