Abstract 171: Impact of Institutional Culture on Rates of Transfusions During Cardiovascular Procedures: The Michigan Experience

Abstract

Objectives: Red blood cell (RBC) transfusions have been associated with morbidity and mortality in both coronary artery bypass grafting (CABG) and percutaneous coronary interventions (PCI). As a mechanism for identifying determinants of RBC practice, we quantified the relationship between a center’s PCI and CABG transfusion rate. Methods: We identified all patients undergoing CABG (n= 16568) or PCI (n=94634) at each of 33 centers from 2010 through 2012 in the state of Michigan and compared perioperative RBC transfusion rates for CABG and PCI at each center. Crude and adjusted transfusion rates were modeled separately. We adjusted for common pre-procedural risk factors (12 for CABG, and 23 for PCI) and report Pearson correlation coefficients based on the crude and risk-adjusted rates. Results: RBC transfusion was more common after CABG (mean 46.5%) than PCI (mean 3.3%), with wide variation across centers for both (CABG min:max, 26.5:71.3; PCI min:max, 1.6:6.0). RBC rates were significantly correlated between CABG and PCI in both crude (r=0.47, p=0.005) and adjusted (r=0.53, p=0.002) analyses, Figure. These findings were consistent when restricting to non-emergent cases (r adj =0.44, p=0.001). Conclusions: RBC transfusion rates were significantly correlated between the CABG and PCI at individual hospitals in Michigan, independent of patient case mix. Future work should explore institutional determinants of RBC transfusions.