Saskatoon Urban Hospital Frozen Plasma Utilization and Appropriateness Audit

Plasma is a blood component frequently used in inappropriate clinical contexts. A 2013 frozen plasma utilization audit in Ontario found that 52% of orders for plasma were inappropriate, while plasma requested for appropriate indications was frequently under-dosed (less than 10 mL/kg administered). Local trends of plasma utilization have not previously been audited. We hypothesized that hospital sites within the former Saskatoon Health Region would have similar rates of inappropriate plasma transfusion and under-dosing as reported by other recent Canadian audits.

This retrospective, quality improvement audit was completed evaluating transfused units of fresh frozen plasma and frozen plasma (collectively known as plasma), given between January and September 2017 at the two largest tertiary care hospitals in Saskatoon, Saskatchewan - Royal University Hospital (RUH) and St. Paul's Hospital (SPH). Data collected included: patient demographics, indication for plasma transfusion, plasma dose, coagulation parameters pre- and post-transfusion, specialty of ordering physician, location of transfusion, and concurrent vitamin K use.

Appropriateness of plasma utilization was judged according to the Ontario Clinical Practice Recommendations for the Use of Frozen Plasma. Appropriate indications for plasma transfusion included: massive hemorrhage, intraoperative coagulopathy during cardiac surgery, and patients with active bleeding or need for invasive procedures with laboratory evidence of coagulopathy (INR [International Normalized Ratio] ≥ 1.5). Inappropriate indications for plasma transfusion included: correction of laboratory evidence of coagulopathy in the absence of bleeding or need for invasive procedures, reversal of warfarin when Prothrombin Complex Concentrate (PCC) was available, reversal of other anticoagulants, and an INR of 1.5 or less or for whom the INR was unknown. Plasma transfusion to patients with INR of 1.5 or less or with an unknown INR was not considered inappropriate in cases of massive hemorrhage. According to the predefined criteria, each plasma transfusion during our study period was individually reviewed and classified as appropriate or inappropriate.

A total of 270 adult and pediatric patients received plasma transfusion during our study period. Patients receiving plasma for therapeutic plasma exchange were excluded. Final analysis included 244 patients, representing 392 transfusion events and 891 units of plasma. Among adult patients at RUH and SPH, 50.5% of plasma transfusions were judged to be inappropriate. The most common inappropriate indication in adult patients (26.5%) was plasma transfusion to patients with an INR of 1.5 or less, or for whom INR was not measured (6.3%). Despite availability of PCC, 5% of plasma orders for adults were for the reversal of warfarin. The average plasma dose ordered for adults was 2 units per transfusion event, which is unlikely to be an appropriate dose for an average sized adult. In adult patients, transfusion of plasma was requested primarily by: critical care physicians (28.6%), cardiac surgeons (16.0%), and general internists (15.3%). Among pediatric patients at RUH, 79.8% of plasma transfusions were judged to be inappropriate, with the most common inappropriate request in pediatric patients (38.5%) cited as hemodynamic support without coagulopathy or massive hemorrhage.

Our study demonstrated that the rate of inappropriate plasma transfusion at two major Saskatoon urban hospital sites was similar to that recently published in Ontario. It is reassuring that plasma transfusion for warfarin reversal was found to be only 5%, suggesting broad awareness of PCC availability. Plasma transfused to adults was found to frequently be under-dosed, suggesting patients are being exposed to the potential risks of plasma transfusion with limited clinical benefit. These results highlight plasma transfusion utilization and appropriateness as an area of educational need among both adult and pediatric clinicians. Implementation of strategies including local clinical practice guidelines for plasma transfusion, plasma order screening by the transfusion medicine laboratory, or a plasma transfusion order set may optimize plasma utilization and enhance patient safety by reducing unnecessary patient exposure to plasma transfusion.