Predicting organ functioning with and without blood transfusion in critically ill patients with anemia

Background To develop a model for the prediction of the (most likely) effect of red blood cell (RBC) transfusion on subsequent organ functioning in nonbleeding critically ill patients with hemoglobin concentrations between 6 and 9 g/dL. Study Design and Methods We conducted a retrospective cohort study using electronic health care data of nonbleeding patients admitted between November 2004 and May 2016 at the intensive care unit (ICU) of the Leiden University Medical Center, The Netherlands. We analyzed the associations between transfusion (yes/no) and next‐day SOFA scores (Sequential Organ Failure Assessment—as a measure for organ functioning) for all observed combinations of hemoglobin values (between 6 and 9 g/dL) and concurrent clinical variables. Results Data of 6425 ICU admission of 5756 critically ill patients with 28,702 hemoglobin values between 6 and 9 g/dL (transfusion decision moments) of which 22.1% were followed by a transfusion were analyzed. The adjusted average difference between the next‐day SOFA score of transfused versus not‐transfused patients was 0.08 (95% confidence interval [CI] −0.03 to 0.18). At singular transfusion decision moments, the score predicted a beneficial effect of transfusion on next‐day SOFA score for some subgroups and medical conditions and a harmful effect in other occasions. Conclusions Among these critically ill patients with hemoglobin concentrations between 6 and 9 g/dL the population average effect of transfusion on the next SOFA score was negligible. Further, our results support caution in clinical decision‐making regarding transfusion of critical ill, nonbleeding ICU patients.