Reconstituted Whole Blood Research Articles

In vitro Analysis of the Hemostatic Properties of Whole Blood Products Prepared with a Platelet-Sparing Leukoreduction Filter

Warm fresh whole blood (WFWB) is an ideal resuscitation fluid for exsanguinating patients but there are myriad logistic and infectious issues associated with its use. Cold whole blood (CWB) may be an acceptable alternative to the reconstituted whole blood (RWB), the current standard of care. A leukoreduction filter has been developed which maintains platelet count while eliminating white blood cells but its effect on platelet function is unknown. We hypothesize that CWB will retain an acceptable functional coagulation profile after filtration and over time. WFWB and CWB samples were obtained from eight donors and four units of RWB were created. The quantitative and qualitative in vitro coagulation profiles of WFWB, RWB, and CWB over time were compared. Filtration was successful at removing white blood cells (5.5 ± 1.2 vs. 0.3 ± 0.3 × 106/L) while retaining an adequate platelet count (172.0 ± 47.0 to 166.0 ± 42.3 × 109/L) and hemoglobin concentration (13.7 ± 0.5 vs. 13.0 ± 0.7 g/dL). Rotational Thromboelastography (ROTEM) results revealed a similar clotting time (CT) before and after filtration (64.9 ± 5.1 vs. 64.1 ± 6.8 s) but a decreased maximum clot firmness (MCF) (58.6 ± 4.2 vs. 54.9 ± 4.6 mm). Platelet aggregation decreased substantially (28.8 ± 6.7 vs. 9.3 ± 2.1 ohm) immediately after filtration. CWB function continued to diminish over time. CWB holds great promise as a surrogate for WFWB, but use of a platelet-sparing LR filter diminishes platelet function almost immediately after filtration.

The whole is greater than the sum of its parts: hemostatic profiles of whole blood variants.

Mounting evidence highlighting the benefits of hemostatic resuscitation has led to a renewed interest in whole blood (WB) and reconstituted WB (RWB). However, few data exist to characterize the clotting profiles of these variants. This study characterizes banked WB variants and RWB in standard 1:1:1 and 2:1:1 transfusion ratios of packed red blood cells, fresh frozen plasma, and platelets (PLTs). We hypothesized that the global hemostatic profile of 1:1:1 RWB is superior to 2:1:1 RWB and that PLT-modified WB (MWB) is superior to 1:1:1 RWB. Twenty-three units of packed red blood cells, fresh frozen plasma, and PLTs were obtained from the regional blood collection center and mixed to create 23 1:1:1 and 23 2:1:1 RWB units. Freshly donated WB units were obtained and used to create 11 of each nonmodified WB (NMWB) (room temperature and cooled) and MWB (room temperature and cooled) variants. International normalized ratio (INR)/partial thromboplastin time (PTT), complete blood cell count, functional studies, and an extensive panel of procoagulant and anticoagulant factor assays were performed on all products. The 1:1:1 RWB had significantly lower INR and PTT (1.31 vs. 1.55, p = 0.0029; 42 seconds vs. 50 seconds, p = 0.0008) and higher activity of factors II, V, VII, VIII, IX, and X; antithrombin III, as well as protein C and higher fibrinogen levels than did 2:1:1 RWB (factor IX, 86% vs. 70%, p = 0.0313; fibrinogen, 242 mg/dL vs. 202 mg/dL, p = 0.0385). There were no differences in INR/PTT or factor activity between MWB and NMWB. However, MWB had greater maximum clot firmness (MCF) by rotational thromboelastometry tissue factor-activated extrinsic clotting cascade measures than did NMWB (MCF, 61 mm vs. 50 mm, p = 0.0031). MWB also had greater MCF by rotational thromboelastometry tissue factor-activated extrinsic clotting cascade measures than did 1:1:1 RWB (MCF, 61 mm vs. 45 mm, p = 0.0005). Although 1:1:1 RWB had a superior clotting profile relative to 2:1:1 RWB, MWB exhibited even better global hemostasis than did 1:1:1 RWB. Characterization of factor-level and functional clotting differences between WB variants is imperative for understanding the clinical benefits of hemostatic resuscitation.