Background: Using Blood Wisely is a national Choosing Wisely Canada (CWC) initiative that challenges hospitals to benchmark themselves on evidence-informed restrictive transfusion strategies, with the aim to decrease inappropriate red blood cell (RBC) transfusions in Canada. We previously assessed transfusion practices among oncology patients at BC Cancer Vancouver during a 12-month period. Here we present the results of a second audit, after implementation of quality improvement (QI) interventions. Methods: BC Cancer Vancouver RBC transfusion records were obtained for the periods of October 2019-September 2020 and April 2021-March 2022. The percentage of transfusions that were single-unit or for hemoglobin (Hg) ≤80 g/L were measured to assess adherence to CWC targets of ≥65% and ≥80%, respectively, for these metrics. QI interventions were implemented after the first audit, including staff education (grand rounds presentation, sitewide email bulletin) and direct engagement of ordering physicians by nursing staff. Uni- and multivariate analyses were used to test associations between patient characteristics and transfusion outcomes. Results: Single-unit transfusions increased from 41% in inpatients (49/120) and 12% in outpatients (69/586) in the first audit, to 86% (126/146) in inpatients (P<0.001)and 34% (170/495) in outpatients (P<0.001) in the second audit. Transfusions for Hg ≤80 g/L increased from 79% (95/120) in inpatients and 66% (384/586) in outpatients, to 93% (136/146) in inpatients (P=0.001) and 78% (384/495) in outpatients (P<0.001). Patient factors associated with restrictive transfusion practices included inpatient status and having a hematological malignancy. Conclusions: In the face of fluctuating RBC shortages, interventions aimed at high-use populations like oncology patients are crucial to reducing transfusion overuse. Through education and prescriber engagement, we successfully reduced the rate of inappropriate RBC transfusions at our institution and achieved the status of a designated Using Blood Wisely Hospital.

*Received any systemic or radiation treatment within 3 months of transfusion.