Risk Factors and Outcome of Transfusion-related Acute Lung Injury in the Critically Ill: a Nested Case-control Study

Objectives: To determine the incidence, risk factors, and outcome of transfusion-related acute lung injury in a cohort of critically ill patients.

Design: In a retrospective cohort study, patients with transfusion-related acute lung injury were identified using the consensus criteria of acute lung injury within 6 hrs after transfusion. Inclusion criterion was a length of intensive care unit admission >48 hrs. Patients developing transfusion-related acute lung injury were matched (on age, sex, and admission diagnosis) to transfused control subjects and patients developing acute lung injury from another origin.

Setting: Tertiary referral hospital.

Patients: All first-admitted patients from November 1, 2004, until October 1, 2007, to the intensive care unit.

Interventions: None.

Measurements And Main Results: Of 5208 admitted patients, 2024 patients had a length of stay >48 hrs, of whom 109 were suspected transfusion-related acute lung injury cases. Compared with transfused control subjects, risk factors for transfusion-related acute lung injury were emergency cardiac surgery (odds ratio, 17.6 [1.8-168.5]), hematologic malignancy (odds ratio, 13.1 [2.7-63.8]), massive transfusion (odds ratio, 4.5 [2.1-9.8]), sepsis (odds ratio, 2.5 [1.2-5.2]), mechanical ventilation (odds ratio, 3.0 [1.3-7.1], and high Acute Physiology and Chronic Health Evaluation II score (odds ratio, 1.1 [1.0-1.1]; p < .03 for all). The volume of platelets and plasma transfused was associated with transfusion-related acute lung injury in the univariate analysis. However, this association disappeared in the multivariate analysis. Compared with acute lung injury control subjects, risk factors for transfusion-related acute lung injury were sepsis (odds ratio, 2.4 [1.1-5.3]) and high Acute Physiology and Chronic Health Evaluation II score (odds ratio, 1.1 [1.0-1.1]), whereas pneumonia (odds ratio, 0.4 [0.2-0.7]) was a negative predictive factor. Patients with transfusion-related acute lung injury had a longer duration of mechanical ventilation compared with transfused control subjects and acute lung injury control subjects (231 [138-472] vs. 71 [46-163] and 70 [42-121] hrs, p < .001). Also, 90-day survival of patients with transfusion-related acute lung injury was lower compared with transfused control subjects and acute lung injury control subjects (53% vs. 75% and 83%, p < .02).

Conclusions: Transfusion-related acute lung injury is common in critically ill patients. Transfusion-related acute lung injury may contribute to an adverse outcome associated with transfusion. This study identifies transfusion-related acute lung injury risk factors, which may aid in assessing the risks and benefits of transfusion in critically ill patients.