Higher intraoperative plasma transfusion volumes are associated with inferior perioperative outcomes

Intraoperative plasma transfusion is common, yet little is known regarding its effects on perioperative coagulation tests or clinical outcomes.

This is a retrospective cohort study of adults receiving intraoperative plasma transfusion at a single center from 2011 to 2015. Relationships between plasma transfusion volume, changes in coagulation test values, and clinical outcomes, including a primary outcome of early postoperative red blood cell (RBC) transfusion, were assessed with multivariable regression analyses. Secondary outcomes included hospital mortality, intensive care unit (ICU)- and hospital-free days, intraoperative RBC transfusions, and estimated blood loss.

A total of 3393 unique patients were included, with median (IQR) transfusion of 2 (2-4) units. In multivariable analyses, higher plasma volumes were associated with worse outcomes, with each 1 mL/kg increase associated with increased odds for postoperative (1.02 [1.01-1.03], p < 0.001) and intraoperative RBCs (1.17 [1.16-1.19], p < 0.001) and fewer ICU- and hospital-free days (mean difference [95% CI], -0.08 [-0.12 to -0.05], p < 0.001; and -0.09 [-0.13 to -0.06], p < 0.001, respectively). Greater decreases in international normalized ratio (INR) following plasma transfusion were associated with decreased odds of postoperative RBCs (0.35 [0.25-0.47], p < 0.001), decreased mortality (0.50 [0.31-0.83], p = 0.007), and increased mean ICU- (1.31 [0.41-2.21], p = 0.004) and hospital-free days (1.15 [0.19-2.10], p = 0.018).

In patients receiving intraoperative plasma transfusion, higher transfusion volumes were associated with inferior clinical outcomes; however, greater improvements in INR were associated with improved outcomes. Future prospective studies are necessary to better define these relationships and to explore plasma transfusion triggers beyond the limitations of INR.