Hemostatic In Vitro Properties of Novel Plasma Supernatants Produced from Late-storage Low-titer Type O Whole Blood

High-dimensional analysis of injured patients reveals distinct circulating proteomic profiles in plasma vs. whole blood resuscitation

Early blood product resuscitation is often essential for optimal trauma care. However, the effects of different products on the underlying trauma-induced coagulopathy and immune dysfunction are not well described. Here, we use high-dimensional analysis and causal modeling in a longitudinal study to explore the circulating proteomic response to plasma as a distinct component versus low-titer O whole blood (LTOWB), which contains plasma. We highlight the differential impacts of plasma and LTOWB on immune mediator levels and the distinct capacity of plasma to modulate coagulation by elevating fibrinogen and factor XIII and reducing platelet factor 4. A higher proportion of plasma in prehospital resuscitation is associated with improved admission time coagulation parameters in patients with severe shock and elevated brain injury markers and reduced post-admission transfusion volumes in those suffering from traumatic brain injury (TBI) and blunt injury. While LTOWB offers broad hemostatic benefits, our findings demonstrate specific advantages of plasma and support individualized transfusion strategies.

Extracellular vesicles in ageing cold-stored whole blood may not compensate for the decreasing haemostatic function in vitro

BACKGROUND

Extracellular vesicles (EVs) have procoagulative properties. As EVs are known to accumulate in stored blood products, we compared the EV content and coagulation capacity of leukoreduced cold-stored whole blood (CSWB) with current prehospital and in-hospital component therapies to understand the role of EVs in the haemostatic capacity of ageing CSWB.

MATERIALS AND METHODS

Blood was obtained from 12 O RhD-positive male donors. CSWB was compared with in-hospital component therapy of red blood cells (RBCs), OctaplasLG and buffy-coat platelets and prehospital component therapy of RBC and lyophilized plasma. Samples were drawn on Days 1 and 14 of CSWB and RBC cold storage. Blood count, haemolysis markers, rotational thromboelastometry, sonorheometry and thrombin generation were analysed. EVs were analysed using nanoparticle tracking analysis and cellular origin was determined using imaging flow cytometry.

RESULTS

There was a trend towards increased production of both platelet and RBC-derived EVs during CSWB storage. Particle count increased during storage, whereas thrombin generation slowed down and in viscoelastic assays, clotting times prolonged, clot formation became impaired, and stiffness of the resulting clot decreased.

CONCLUSION

Both platelet and RBC-derived EVs increased in number in CSWB during storage. This did not appear to compensate for the in vitro decreasing haemostatic capacity of ageing CSWB, suggesting EVs produced during storage may not have active procoagulative effects, but rather reflect the ageing of blood cells.

A Perioperative Blood Management Algorithm Aimed at Conservation of Platelets in Clinical Practice: The Role of the Anesthesiologist in Decision-Making

Platelet dysfunction and thrombocytopenia are associated with postoperative morbidity not only from modifiable preoperative factors but also from a lack of local patient blood management algorithms. In this regard, platelet transfusions have risen after the COVID-19 pandemic. Simultaneously, there has been a shortage of donors. It is logical, therefore, that each hospital should develop a triage tool, posting their algorithm on walls. Anesthesiologists should assist in planning a strategy to minimize blood transfusions while improving tissue oxygenation. A flowchart posted in each operating theatre may be customized per patient and hospital. Clinicians need reminders to draw a prothrombin time, fibrinogen, complete blood count every hour, and the appropriate threshold to transfuse. In summary, anesthesiologists are often unable to have a discussion with a patient until the preoperative day; thus, the onus falls on our surgical colleagues to reduce risk factors for coagulopathy or to delay surgery until after proper consultants have optimized a patient. The most important problems that an individual patient has ideally should be listed in a column where an anesthesiologist can write a timeline of key steps across a row, corresponding to each problem. If a handoff in the middle of the case is required, this handoff tool is superior to simply checking a box on an electronic medical record. In summary, in the operating suite, an anesthesiologist should emphasize the importance of a multidisciplinary approach. Continuing education, regular stakeholder meetings, and posters can assist in reinforcing algorithms in clinical practice.