Red blood cell transfusion practices in acute lung injury: what do patient factors contribute?
OBJECTIVE
To describe red blood cell (RBC) transfusion practices and evaluate the association between patient-related factors and pretransfusion hemoglobin concentration in acute lung injury (ALI).


METHODS
Secondary analysis of prospectively collected data.


METHODS
Nine intensive care units (ICUs) in three teaching hospitals in Baltimore, MD.


METHODS
Two hundred forty-nine consecutive patients with ALI requiring mechanical ventilation.


METHODS
None.


RESULTS
Simple and multiple linear regression analyses were used to evaluate the association between the nadir hemoglobin concentration on the day of initial RBC transfusion and 20 patient-level demographic, clinical and ICU treatment factors as well as ICU type. Of 249 patients with ALI, 47% received an RBC transfusion in the ICU without evidence of active hemorrhage or acute cardiac ischemia. The mean (sd) nadir hemoglobin on the day of first transfusion was 7.7 (1.1) g/dL with 67%, 36%, 15%, and 5% of patients transfused at >7, >8, >9, and >10 g/dL, respectively. Transfused patients received a mean (sd) of 5 (6) RBC units from ALI diagnosis to ICU discharge. Prehospital use of iron or erythropoietin and platelet transfusion in the ICU were independently associated with lower pretransfusion hemoglobin concentrations. No patient factors were associated with higher hemoglobin concentrations. Admission to a surgical (vs. medical) ICU was independently associated with a 0.6 g/dL (95% confidence interval 0.1-1.1 g/dL) higher pretransfusion hemoglobin.


CONCLUSIONS
Patients with ALI commonly receive RBC transfusions in the ICU. The pretransfusion hemoglobin observed in our study was lower than earlier studies, but a restrictive strategy was not universally adopted. Patient factors do not explain the gap between clinical trial evidence and routine transfusion practices. Future studies should further explore ICU- and physician-related factors as a source of variability in transfusion practice.
Murphy
David J
DJ
Division of Pulmonary/Critical Care Medicine, Johns Hopkins University, Baltimore, MD, USA.
Howard
David
D
Muriithi
Angela
A
Mendez-Tellez
Pedro
P
Sevransky
Jonathan
J
Shanholtz
Carl
C
Netzer
Giora
G
Pronovost
Peter J
PJ
Needham
Dale M
DM
D055371:Acute Lung Injury / Q000097:blood / Q000628:therapy*; D017707:Erythrocyte Transfusion / Q000706:statistics & numerical data*; D005260:Female; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D008297:Male; D008875:Middle Aged
D006454:Hemoglobins