Evaluation of the overnight hold of whole blood at room temperature, before component processing: platelets (PLTs) from PLT-rich plasma

Buffy coat platelets coming to America: Are we ready?

BACKGROUND

Buffy coat (BC) platelets (PLTs) have been used globally for many years. In 2004 Canadian Blood Services (CBS) made the decision to transition from PLT-rich plasma (PRP) to BC PLTs. We reviewed the benefits and manufacture process of BC and the implementation challenges involved.

STUDY DESIGN AND METHODS

A literature review was performed in the following areas: BC efficacy, donor population shifts, production and good stewardship of PLTs, logistic considerations with overnight holds, advantages of the overnight hold, the CBS experience, licensure and standards, and changes needed to produce BC PLTs in the United States. The aim was to analyze current practice and identify possible actions for blood centers and hospitals.

RESULTS

Implementation of BC would offer an additional source of PLTs to address the growing elderly population and the declining apheresis donor base. Substantial logistic, operational, and financial benefits were seen when CBS transitioned to BC with overnight hold.

CONCLUSIONS

Buffy coat blood products are widely used throughout the world. Recent conversion from PRP to BC by CBS showed that conversion can be accomplished with planning, communication, and partnership from all stakeholders. In conclusion, BC PLTs are worth serious consideration in the United States, but regulatory barriers in the United States will need to be addressed.

Clotting functional stability of withdrawing blood in storage for acute normovolemic hemodilution: a pilot study

Purpose

This study was conducted to time-course changes of clotting function of withdrawing blood for acute normovolemic hemodilution (ANH).

Methods

Twelve enrolled patients who underwent ANH from August, 2018 to January, 2019. Blood was withdrawn into blood collection pack and shaken at 60–80 rpm for 24 h in room temperature. Clot formation was evaluated using rotational thromboelastometry (ROTEM™) just after blood withdrawal (control) and 4, 8, 12 and 24 h after blood withdrawal. We compared with the control value and each value of extrinsically-activated test with tissue factor (EXTEM), intrinsically-activated test using ellagic acid (INTEM) and fibrin-based extrinsically activated test with tissue factor (FIBTEM).

Results

Maximum clot firmness (MCF) of FIBTEM did not change significantly. MCF of EXTEM was significantly decreased time-dependent manner but all MCF of EXTEM were within a normal range. Maximum percent change in MCF of EXTEM was 12.4% [95% confidence interval (CI): 9.0–15.8%]. The difference in the maximum clot elasticity (MCE) between EXTEM and FIBTEM (MCE_EXTEM−MCE_FIBTEM) was significantly decrease from 8 h after blood withdrawal. Maximum percent change in MCE_EXTEM−MCE_FIBTEM was 30.2% (95% CI:17.6–42.9%) at 24 h after blood withdrawal.

Conclusion

Even though the MCE significantly decreased in a time-dependent manner, MCF of FIBTEM and EXTEM was normal up to 24 h storage. The blood of ANH can use for the purpose of hemostasis at least 8 h stored at room temperature after blood withdrawal. Future studies are needed to elucidate the clinical impact on the patient after delayed transfusion of ANH blood with regard to patient’s hemostasis.

Electronic supplementary material

The online version of this article (10.1007/s00540-020-02856-x) contains supplementary material, which is available to authorized users.

The purified vepoloxamer prevents haemolysis in 42-day stored, DEHP/PVC-free red blood cell units

BACKGROUND

Use of the plasticiser di(2-ethylhexyl) phthalate (DEHP) in polyvinyl chloride (PVC) blood bags poses a potential dilemma. The presence of DEHP in blood bags has been shown to be beneficial to red blood cells during storage by diminishing haemolysis. However, DEHP use in PVC may be carcinogenic or estrogenising. Vepoloxamer is a poloxamer with rheological and cytoprotective rheological properties and a favourable toxicity profile in clinical trials. We hypothesised that vepoloxamer may be sufficient to replace the plasticiser DEHP to prevent elevated haemolysis while conserving the biochemical and redox potential++ in RBCs stored for up to 42 days.

MATERIALS AND METHODS

Paired analyses of aliquots from pooled RBC suspensions of ABO identical donors were aseptically split into test storage containers (DEHP/PVC or DEHP-free/ethylene vinyl acetate [EVA]) supplemented with or without vepoloxamer (at concentrations of 0.1, 1, 5 or 7.89 mg/mL) and cold stored for up to 42 days.

RESULTS

Vepoloxamer significantly prevented the increased haemolysis induced by the absence of DEHP in EVA bags in a dose-dependent manner by days 28 and 42 of storage (approx. 50% reduction of the maximum concentration of vepoloxamer; p<0.001). There was an inverse correlation between the concentration of vepoloxamer used and the haemolysis rate (r2=0.27, p<0.001) and a direct correlation between haemolysis and phosphatidylserine (PS) exposure (r2=0.42; p<0.01). Increased osmotic fragility and shear induced deformability of 42-day stored RBC in EVA bags was significantly corrected by the addition of vepoloxamer.

DISCUSSION

Vepoloxamer, in a concentration-dependent fashion, is able to partly rescue the increased haemolysis and PS exposure induced by the absence of the commonly used plasticiser DEHP. These results provide initial but strong evidence to support vepoloxamer use to replace DEHP in long-term storage of RBC.

Platelet Immobilization on Supported Phospholipid Bilayers for Single Platelet Studies

The worldwide cardiovascular disease (CVD) epidemic is of grave concern. A major role in the etiology of CVDs is played by the platelets (thrombocytes). Platelets are anuclear cell fragments circulating in the blood. Their primary function is to catalyze clot formation, limiting traumatic blood loss in the case of injury. The same process leads to thrombosis in the case of CVDs, which are commonly managed with antiplatelet therapy. Platelets also have other, nonhemostatic functions in wound healing, inflammation, and tissue regeneration. They play a role in the early stages of atherosclerosis and the spread of cancer through metastases. Much remains to be learned about the regulation of these diverse platelet functions under physiological and pathological conditions. Breakthroughs in this regard are expected to come from single platelet studies and systems approaches. The immobilization of platelets at surfaces is advantageous for developing such approaches, but platelets are activated when they come in contact with foreign surfaces. In this work, we develop and validate a protocol for immobilizing platelets on supported lipid bilayers without activation due to immobilization. Our protocol can therefore be used for studying platelets with a wide variety of surface-sensitive techniques.

Whole blood: the future of traumatic hemorrhagic shock resuscitation

Toward the end of World War I and during World War II, whole-blood transfusions were the primary agent in the treatment of military traumatic hemorrhage. However, after World War II, the fractionation of whole blood into its components became widely accepted and replaced whole-blood transfusion to better accommodate specific blood deficiencies, logistics, and financial reasons. This transition occurred with very few clinical trials to determine which patient populations or scenarios would or would not benefit from the change. A smaller population of patients with trauma hemorrhage will require massive transfusion (>10 U packed red blood cells in 24 h) occurring in 3% to 5% of civilian and 10% of military traumas. Advocates for hemostatic resuscitation have turned toward a ratio-balanced component therapy using packed red blood cells-fresh frozen plasma-platelet concentration in a 1:1:1 ratio due to whole-blood limited availability. However, this "reconstituted" whole blood is associated with a significantly anemic, thrombocytopenic, and coagulopathic product compared with whole blood. In addition, several recent military studies suggest a survival advantage of early use of whole blood, but the safety concerns have limited is widespread civilian use. Based on extensive military experience as well as recent published literature, low-titer leukocyte reduced cold-store type O whole blood carries low adverse risks and maintains its hemostatic properties for up to 21 days. A prospective randomized trial comparing whole blood versus ratio balanced component therapy is proposed with rationale provided.

A comparison study of the blood component quality of whole blood held overnight at 4°c or room temperature

Background. The use of plasma frozen within 24 hrs is likely to increase. Whole blood (WB) and buffy coats (BCs) can be held for a few hrs or overnight before processing. Methods. Twenty-four bags of WB for plasma and 12 bags for platelet (PLT) concentrates were collected. The fresh frozen plasma (FFP) was prepared within 6 hrs. I-FP24 and II-FP24 samples were prepared either from leukodepleted WB that was held overnight or from WB that was held overnight before leukodepletion. The PLT concentrates (PCs) were prepared from BCs within 6 hrs (PC1) and within 18 to 24 hrs (PC2). The typical coagulation factors and some biochemical parameters were determined. Results. Compared to the FFP samples, the levels of FVII and FVIII in the I-FP24 and II-FP24 samples decreased significantly. The pH, Na⁺, LDH, and FHb levels differed significantly between II-FP24 and FFP. Compared to PC1, PC2 exhibited lower pH, pO₂, and Na⁺ levels, a higher PLT count, and increased pCO₂, K⁺, Lac, and CD62P expression levels. Conclusion. FP24 is best prepared from WB that was stored overnight at 4°C and then leukodepleted and separated within 24 hrs. PCs are best produced from BCs derived from WB that was held overnight at room temperature.

Standardization of CD62P measurement: results of an international comparative study

BACKGROUND AND OBJECTIVES

Despite long being a mainstay in describing platelet activation via degranulation, interlaboratory variation remains an issue in measurement of membrane CD62P by flow cytometry. Our objective was to identify actions that may minimize this variation.

MATERIALS AND METHODS

Sixteen laboratories participated in an international comparative study. Two sets of platelet samples were prepared in one laboratory. Set 1 was stained and fixed; set 2 was fixed and required staining at participating laboratories. A single-staining method was used, and platelet populations were selected based on forward scatter/side scatter characteristics. Calibration beads were used to standardize measurement across different instruments.

RESULTS

There was a large discrepancy in reported CD62P values among study sites [interlaboratory coefficient of variance (CV): 36-78%]. When electronic data were re-analysed by a single analyst using a consistent gating strategy and a stable reference point, variation decreased markedly (CV < 12%), indicating a problem with isotype control samples, possibly related to sample fixation or shipment.

CONCLUSION

Consensus regarding gating strategies and use of a reliable reference point would greatly improve agreement in interlaboratory CD62P measurement.

Evaluation of overnight hold of whole blood at room temperature before component processing: effect of red blood cell (RBC) additive solutions on in vitro RBC measures

BACKGROUND

Whole blood (WB) can be held at room temperature (18-25°C) up to 8 hours after collection; thereafter the unit must be refrigerated, rendering it unsuitable for platelet (PLT) production. Overnight hold at room temperature before processing has logistic advantages, and we evaluated this process in an international multicenter study for both buffy coat (BC)- and PLT-rich plasma (PRP)-based blood components and compared three red blood cell (RBC) additive solutions (ASs) for their ability to offset effects of overnight hold.

STUDY DESIGN AND METHODS

Nine centers participated; seven used the BC method, and two used the PRP method. Four WB units were pooled and split; 1 unit was processed less than 8 hours from collection (Group A), and the other three (Groups B, C, and D) were held at room temperature and processed after 24 to 26 hours. RBCs in Groups A and B were resuspended in saline-adenine-glucose-mannitol, Group C in phosphate-adenine-guanosine-glucose-saline-mannitol, and Group D in ErythroSol-4 RBCs were stored at 2 to 6°C for 49 days.

RESULTS

RBCs from overnight-held WB had lower 2,3-diphosphoglycerate (2,3-DPG) and higher adenosine triphosphate (ATP). At the end of storage there were no differences between groups, apart from a slightly higher hemolysis in Group B. ErythroSol-4 showed a slightly higher initial ATP and 2,3-DPG content, but at the end of storage no differences were found.

CONCLUSION

Overnight hold of WB before processing has no lasting deleterious effects on in vitro quality of subsequently prepared components. The use of different RBC ASs did not appear to offer significant advantages in terms of RBC quality at the end, regardless of the processing method.