There Will Be Blood: A 5-Year Review of Transfusions Associated With CABGs and Single Valve Repairs at a Tertiary Cardiac Centre, and Their Impact on Patient Hospital Length of Stay

Abstract

Purpose: Cardiac surgery as a discipline carries some of the highest use of blood products. While appropriate use of these can be vital to the care of patients, it is not without considerable risk, including an increased length of stay (LoS). We sought to examine the impact red blood cell (RBC) transfusion had on this variable at our institution, and whether it was modified by their type of surgery, and if this magnitude correlated with the volume of units used. Methodology: We conducted a retrospective observational study at a single tertiary cardiac unit, reviewing all patients between January 2011 to December 2015 who had an on-pump CABGs or single valve repair/replacement. In addition to the number of units administered, additional variables were collected to allow for risk stratification. The primary outcome measurement was LoS. Results: Of the 795 identified, 332 (41.8%) received a RBC transfusion, with a total of 1035 units transfused. Univariate analysis yielded a 44% longer LoS (IRR: 1.44; 95% CI 1.35-1.55; p < 0.0001) in individuals who received a transfusion. This remained significant on multivariate analysis (IRR: 1.40; 95% CI 1.25-1.51; p < 0.0001). For patients who received a RBC transfusion, on multivariate analysis every additional RBC unit given was associated with a 10% longer LoS (IRR: 1.10; 95% CI 1.07-1.13; p < 0.0001). Conclusion: Patients who received a RBC transfusion at our institution had a 40% longer LoS, with a 10% increase for every unit transfused. While patients who receive a transfusion may represent a more unwell population, correcting for this within our population suggests that there is a direct impact of RBC transfusion on patient outcomes.