Institutional Variability in Red Blood Cell Transfusion With Coronary Bypass in a Statewide Database

Background: The decision to perform transfusion is common but varies among centers and surgeons. This study looked at variables associated with red blood cell (RBC) transfusion in a statewide database. The study aimed to understand discrepancies in transfusion rates among hospitals and to establish whether the hospital itself was a significant variable in transfusion, independent of variables known to affect transfusion in patients undergoing cardiac surgical procedures. Methods: The Maryland Cardiac Surgery Quality Initiative is a consortium of centers in the state. Patients undergoing isolated coronary artery bypass grafting from January 2018 to June 2020 from 10 centers in Maryland were included. Multivariable logistic regression was used to determine probability of RBC transfusion with covariates, including age, preoperative hemoglobin value, The Society of Thoracic Surgeons predicted risk of mortality, emergency status, preoperative adenosine diphosphate receptor blocker use, sex, body mass index, and off-pump status. Results: A total of 5343 patients were included and had an overall RBC transfusion rate of 30.3% (range, 11.3%-55.8%). There was significant variability in the incidence of RBC transfusion among hospitals (χ² = 604.7; P < .001). After covariate adjustment, a significant effect of hospital on transfusion remained (Wald = 547.3; P < .001). Hospital variation in RBC transfusion was not correlated with hospital variation in median age (P = .467), hemoglobin (P 0 855), The Society of Thoracic Surgeons predicted risk of mortality (P = .855), or sex (P = .726). Conclusions: In a statewide analysis, wide variability in transfusion rates was observed, with hospital-specific management strongly associated with RBC transfusion. This study suggests that RBC transfusion may be affected by the culture and practices of an institution independent of clinical and demographic variables.