The association between intraoperative cell salvage and red blood cell transfusion in cardiac surgery – an observational study in a patient blood management centre

BACKGROUND: Cell salvage (CS) is an integral part of patient blood management (PBM) and aims to reduce allogeneic red blood cell (RBC) transfusion. METHODS: This observational study analysed patients scheduled for elective cardiac surgery requiring cardiopulmonary bypass (CPB) between November 2015 and October 2018. Patients were divided into a CS group (patients receiving CS) and a control group (no CS). Primary endpoints were the number of patients exposed to allogeneic RBC transfusions and the number of RBC units transfused per patient. RESULTS: A total of 704 patients undergoing cardiac surgery were analysed, of whom 338 underwent surgery with CS (CS group) and 366 were without CS (control group). Intraoperatively, 152 patients (45%) were exposed to allogeneic RBC transfusions in the CS group and 93 patients (25%) in the control group (P < 0.001). Considering the amount of intraoperative blood loss, regression analysis revealed a significant association between blood loss and increased use of RBC units in patients of the control compared to the CS group (1000 mL: 1.0 vs. 0.6 RBC units; 2000 mL: 2.2 vs. 1.1 RBC units; 3000 mL: 3.4 vs. 1.6 RBC units). Thus, CS was significantly associated with a reduced number of allogeneic RBCs by 40% for 1000 mL, 49% for 2000 mL, and 52% for 3000 mL of blood loss compared to patients without CS. CONCLUSIONS: Cell salvage was significantly associated with a reduced number of allogeneic RBC transfusions. It supports the beneficial effect of CS in cardiac surgical patients as an individual measure in a comprehensive PBM program. CLINICAL TRIAL NUMBER: ClinicalTrials.gov, NCT02147795 (URL: https://clinicaltrials.gov/ct2/show/NCT02147795)