Transfusion not superior to no transfusion at an Hbg of 7.0 g/dL in critically ill patients: Study

In critically ill patients, a haemoglobin transfusion threshold of <7.0 G/dl compared to <10.0 G/dl improves organ dysfunction. However, it is unclear if transfusion at a haemoglobin of <7.0 g/dL is superior to no transfusion.

A group of researchers conducted a study to compare levels of organ dysfunction between transfusion and no transfusion at a haemoglobin threshold of <7.0 G/dl among critically ill patients using quasi-experimental regression discontinuity methods.

Researchers performed regression discontinuity analysis using haemoglobin measurements from patients admitted to ICUs in three cohorts (MIMIC-IV, eICU, and Premier Inc.), estimating the change in organ dysfunction (modified sequential organ failure assessment score) in the 24–72-hour window following each haemoglobin measurement.

They compared haemoglobin levels just above and below 7.0 g/dL using a 'fuzzy' discontinuity approach, based on the concept that measurement noise pseudorandomizes similar haemoglobin levels on either side of the transfusion threshold. Results: A total of 11,181, 13,664, and 167,142 patients were included in the MIMIC-IV, eICU, and Premier cohorts, respectively. Patient characteristics below the threshold did not differ from those above the threshold, except that crossing below the threshold resulted in a >20% absolute increase in transfusion rates in all three cohorts. Transfusion was associated with increases in hemoglobin level in the subsequent 24-72 hours (MIMIC-IV 2.4 [95% CI 1.1, 3.6] g/dL; eICU 0.7 [95% CI 0.3, 1.2] g/dL; Premier 1.9 [95% CI 1.5, 2.2] g/dL), but not with improvement in organ dysfunction (MIMIC-IV 4.6 [95% CI -1.2, 10] points; eICU 4.4 [95% CI 0.9, 7.8] points; Premier 1.1 [95% CI -0.2, 2.3] points), compared to no transfusion.

Thus, the researchers concluded that transfusion was not associated with improved organ dysfunction compared to no transfusion at a haemoglobin threshold of 7.0 g/dL, suggesting that evaluation of transfusion targets other than a haemoglobin threshold of 7.0 G/dl may be warranted.

Reference:

Red Blood Cell Transfusion at a Hemoglobin Threshold of Seven g/dL in Critically Ill Patients: A Regression Discontinuity Study by Nicholas A Bosch, et al. published in the Annals of the American Thoracic Society.

https://www.atsjournals.org/doi/abs/10.1513/AnnalsATS.202109-1078OC