A prospective non-inferiority trial of pathogen reduced platelets compared to non-pathogen reduced platelets for correction of viscoelastic platelet function testing in cardiac surgery.

Abstract

Background: Cardiac surgery on cardiopulmonary bypass (CPB) may alter platelet (PLT) function causing bleeding. The goal of this study is to evaluate the hemostatic effect of PRT-PLTs compared to untreated PLTs stored in platelet additive solution (PAS) following transfusion in bleeding patients undergoing cardiac surgery on CPB.

Methods: In this single-center, prospective single-blinded two-arm noninferiority trial, patients being weaned off CPB were allocated to either a PRT-PLT or a standard PAS-PLT. The primary outcome was the change in maximum amplitude (ΔMA) on thromboelastographic testing (TEG) from pre- to post-transfusion. The non-inferiority margin was chosen as 50% of the ΔMA observed with PAS-PLT using a 1-sided 95% confidence interval. The secondary outcomes included the volume of chest tube drainage (CTD) and the number of blood products transfused during the first 24 h post-surgery.

Results: A modified intention-to-treat analysis included 90 patients (48 PRT-PLTs; 42 PAS-PLTs). The ΔMA for PRT-PLT was 2.93 mm (95% CI 1.52-4.34) and was lower than that achieved with PAS-PLT at 5.68 mm (95% CI 3.26-8.09) (2-tailed p = .052). The ratio of ΔMA for PRT-PLT relative to PAS-PLT was estimated at .52 with a 90% confidence interval (.29, .89) and did not meet the non-inferiority criterion (>.5). The CTD and the number of blood products transfused during the first 24 h post-surgery were similar in both arms.

Conclusion: PRT-PLT transfusion results in lower responses in viscoelastic testing compared to PAS-PLT, although clinical outcomes with respect to blood component utilization and chest tube drainage were similar.