Effect of 24-hour whole-blood storage on plasma clotting factors

Stability of Hemostasis Parameters in Whole Blood, Plasma, and Frozen Plasma: Literature Review and Recommendations of the SFTH (French Society of Thrombosis and Haemostasis)

Preanalytical sample management is critical for a proper assessment of hemostasis parameters, and may differ depending on prescribed tests or additional tests considered to be necessary after initial results. Although there is quite vast literature on this issue, the Working Group of the French Society of Thrombosis and Haemostasis (SFTH) deemed it necessary to make an in-depth literature review and propose recommendations for the proper handling of samples prior to hemostasis assays. This extensive assessment is accessible on-line in French at the SFTH website. Here, a more synthetic view of these recommendations is proposed, supported by easy-to-use tables. The latter respectively deal with the stability of whole blood or fresh plasma, frozen samples, and proper handling of samples forwarded on dry ice. Procedures are classified as recommended, acceptable, not conformed and lacking data. This work involved the retrieval of 125 references, first screened by a working group of 6 experts, then reviewed by 20 other experts in the field. The highly detailed conditions summarized in these tables will hopefully help hemostasis laboratories to secure the conditions recommended for sample collection and transportation. Moreover, as some conditions clearly lacked recommendations, this review can open new fields of investigation for hemostasis preanalytics.

Evaluation of bacterial growth, effects on albumin, and coagulation factors in canine fresh frozen plasma administered as continuous rate infusion exposed to room temperature for 12 hours

OBJECTIVES

To determine the risk of bacterial growth and to analyze the stability of albumin and coagulation factors in canine fresh frozen plasma (FFP) units exposed to room temperature (24°C) administered as a continuous rate infusion (CRI) for 12 hours.

DESIGN

Ex vivo study.

SETTING

University teaching hospital and pet blood bank.

ANIMALS

None.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

An FFP CRI was simulated to replicate the standard routine procedure used in dogs. Plasma samples were collected before starting the CRI (H0), after 4 hours (H4), and after 12 hours (H12). Bacterial culture of FFP was performed and albumin concentration and specific activity levels for factors V, VII, VIII, and IX were measured and compared. All plasma culture results were negative. There were no statistically significant differences at any time point in the factor VIII activity (median 105.5% [range, 75.6%-142.0%] at H0; median 107.8% [range, 75.0%-172.7%] at H4; and median 112.1% [range, 81.7%-171.0%] at H12); factor IX activity (median 119.3% [range, 89.1%-175.9%] at H0; median 123.1% [range, 72.5%-172.7%] at H4; and median 118.3% [range, 86.6%-177.5%] at H12); or albumin concentration (median 21.0 g/L [range, 17.0-23.0 g/L] at H0 and median 20.0 g/L [range, 17.0-24.0 g/L] at H12). A slight but significant increase in factor V activity was observed when comparing H0 (median 107.0% [range, 71.0%-159.0%]) to H4 (median 117.7% [range, 71.0%-176.7%]) (P = 0.002) or H12 (median 116.2% [range, 71.0%-191.6%]) (P = 0.001). A slight but significant increase in factor VII activity was observed when comparing H0 (median 115.4% [range, 70.6%-183.7%]) to H4 (median 118.2% [range, 82.7%-194.6%]) (P = 0.005); H0 to H12 (median 128.7% [range, 86.4%-200.0%]) (P < 0.001); and H4 to H12 (P = 0.002).

CONCLUSIONS

FFP CRI at room temperature for 12 hours could be considered safe with regard to risk for bacterial growth and also effective by providing albumin and clotting factors.

International Council for Standardization in Haematology recommendations for laboratory measurement of factor VIII and FIX type I inhibitors

This guidance document has been prepared on behalf of the International Council for Standardisation in Hematology. The aim of the document is to provide guidance and recommendations on the measurement of factor VIII (FVIII) and factor IX (FIX) inhibitors. After an introduction on the clinical background and relevance of factor VIII and factor IX inhibitor testing, the following aspects of laboratory testing are included: screening for inhibitors, assay principle, sample requirements, testing requirements and interpretation, quality assurance, interferences and recent developments. This guidance document focusses on recommendations for a standardised procedure for the laboratory measurement of FVIII and FIX type I inhibitors. The recommendations are based on published data in peer-reviewed literature and expert opinion.

Effects of room temperature and cold storage on the metabolic and haemostatic properties of whole blood for acute normovolaemic haemodilution

Background

Acute normovolaemic haemodilution (ANH), as a blood-conservation technique, avoids the need for allogeneic blood transfusions. The historic practice of cold-storing type-O whole blood (WB) in military fields popularised the transfusion of refrigerated WB to treat acute bleeding. In this study, we compared the effects of room temperature (RT) and refrigeration up to 24 hours on the coagulation properties of WB for ANH.

Materials and methods

Each WB sample, collected from 12 male volunteers, was divided into two parts, one stored at RT and the other refrigerated for 24 hours. Complete blood counts (CBC), blood gas levels, and coagulation profiles were measured, and rotational thromboelastometry (ROTEM) measurements were performed at the initial collection time point (baseline) and at 6, 12, and 24 hours after initial collection.

Results

The preservation of platelet aggregation response induced by arachidonic acid and adenosine diphosphate was better in cold-stored WB compared to that in RT-stored WB. The platelet aggregation response induced by thrombin receptor-activating peptide 6 was significantly decreased in all samples after 24 hours of storage when compared with that at baseline. The lactate levels in WB stored at RT increased significantly after 6 hours of storage compared to that of cold-stored samples. There were no significant differences in CBC, coagulation parameters, and ROTEM variables between the cold-stored and RT-stored WB samples.

Conclusion

WB for ANH stored in the refrigerator showed better metabolic characteristics after 6 hours of storage and better aggregation response after 12 hours of storage than WB stored at RT.

Stability of coagulation parameters in plasma samples at room temperature after one freeze/thaw cycle

INTRODUCTION

Sample freezing is a part of routine laboratory tasks because some coagulation parameters are analysed in batches to optimize reagent consumption. The coagulation parameter stability in fresh and frozen samples has been described, but data are scarcer after thawing. This study objective was to determine the stability of the main coagulation parameters (from blood withdrawn on siliconized CTAD tubes and double-centrifuged) after one freeze/thaw cycle to generate procedures for appropriate handling, storage and testing.

METHODS

Prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen, D-dimers, clotting factors (F), protein C, protein S, antithrombin, lupus anticoagulant (LA)-sensitive aPTT and diluted-Russel's viper venom time (dRVVT) were assessed in 60 plasma samples (n=30, normal range and n=30, outside the normal range). Thirty samples from anticoagulated patients [unfractionated heparin (UFH), low-molecular weight heparin (LMWH), apixaban or rivaroxaban] were assessed using specific anticoagulant assays. Frozen samples were thawed, and assays were performed at 15 min, 2, 4 and 6 h after thawing. The coagulation parameter stability was assessed with the method of rejection limit.

RESULTS

After thawing, aPTT, PT, fibrinogen, D-dimers, FII, FV, FX, FIX, FXI, FXII, PC and UFH anti-Xa activity remained stable for at least 6 h, FVII for 5 h, PS, AT, dRVVT screen assay and LMWH anti-Xa activity for 4 h, and LA-sensitive aPTT and apixaban-specific anti-Xa activity for 3 h. FVIII, dRVVT confirm assay and rivaroxaban specific anti-Xa activity were stable for 2 h.

CONCLUSION

These results suggest that sample stability for some haemostasis assays is limited after thawing.

International Council for Standardization in Haematology (ICSH) recommendations for processing of blood samples for coagulation testing

This guidance document has been prepared on behalf of the International Council for Standardization in Haematology (ICSH). The aim of the document is to provide guidance and recommendations for the processing of citrated blood samples for coagulation tests in clinical laboratories in all regions of the world. The following areas are included in this document: Sample transport including use of pneumatic tubes systems; clots in citrated samples; centrifugation; primary tube storage and stability; interfering substances including haemolysis, icterus and lipaemia; secondary aliquots-transport, storage and processing; preanalytical variables for platelet function testing. The following areas are excluded from this document, but are included in an associated ICSH document addressing collection of samples for coagulation tests in clinical laboratories; ordering tests; sample collection tube and anticoagulant; preparation of the patient; sample collection device; venous stasis before sample collection; order of draw when different sample types are collected; sample labelling; blood-to-anticoagulant ratio (tube filling); influence of haematocrit. The recommendations are based on published data in peer-reviewed literature and expert opinion.

An overview on the investigation of nanomaterials' effect on plasma components: immunoglobulins and coagulation factor VIII, 2010-2020 review

FVIII and immunoglobulins (Igs) are the most prominent plasma proteins, which play a vital role in plasma hemostasis. These proteins have been implemented frequently in protein therapy. Therefore, their maintenance, durability, and stability are highly essential. Herein, various approaches to improve protein functions have been investigated, such as using recombinant protein replacement. In comparison, advances in nanotechnology have provided adequate context to boost biomaterial utilization. In this regard, the applications of various nanoparticles such as polymeric nanomaterials (PEG and PLGA), metal nanoparticles, dendrimers, and lipid based nanomaterials (liposomes and lipid nanoparticles) in stability and the functional improvement of antibodies and coagulation factor VIII (FVIII) have been reviewed from 2010 to 2020. Reviewing related articles has shown that not only can nanomaterials adequately protect the structure of proteins, but have also improved proteins' functions in some cases. For example, the high rate of FVIII instability has been successfully enhanced by bio-PEGylation. Also, utilizing PEGylated liposomes, using the PEG-lip technique for coating nanostructures, leads to FIIIV half-life prolongation. Hence, PEGylation had most impact on the stability of FVIII. Likewise, PEG-coated liposome nano-carriers also presented such a good effect on stability improvements for FVIII due to their ability to tune the immune system by reducing FVIII immunogenicity. Similarly, Ig PEGylation and conjugation to magnetic nanoparticles resulted in increased half-life and better purification of Igs, respectively, without any loss in structural or functional features. Consequently, metal-organic frameworks and recent hybrid systems have been introduced as promising nanomaterials in biomedical applications. As far as we know, this is the first study in this field, which considers the applications of nanoparticles for improving the storage and stability of antibodies and coagulation FVIII.

Impact of specific preclinical variables on coagulation biomarkers in cancer-associated thrombosis

Coagulation biomarkers are being actively studied for their diagnostic and prognostic value in patients with venous thromboembolism and cancer, as well as in the study of pathogenic mechanisms between cancer and thrombosis. For the results of such studies to be accurate and reproducible, attention must be paid to minimize sources of error in all phases of testing. The pre-analytical phase of laboratory testing is known to be fraught with the majority of errors. Coagulation testing is particularly susceptible to conditions during collection, processing, transport and storage of specimens which can lead to clinically significant errors in results. In addition, changes in pre-analytical conditions can impact different biomarkers differently. Therefore, research studies investigating coagulation biomarkers must carefully standardize not just the analytical phase, but also the pre-analytical phase of testing to ensure accuracy and reliability. We briefly review the impact of pre-analytical conditions on coagulation testing in general, and on specific biomarkers in cancer and thrombosis. In addition, we provide recommendations to reduce pre-analytical errors by developing and sharing standard operating procedures that specifically target standardization of methodologies for collecting specimens and measuring current and emerging coagulation biomarkers in cancer studies.

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.

A Preliminary Study on Coagulation Parameters and Sterility of Thawed Refrozen Fresh Frozen Plasma

Thawed fresh frozen plasma (FFP) if not used within 6 h, may have to be discarded due to the risk of contamination and uncertainty about its quality. The main objective of this study was to evaluate the levels of coagulation Factor II (FII), Factor VIII (FVIII), fibrinogen and bacterial growth in thawed refrozen FFP. Thirty FFP samples were collected from healthy donors. FFP were thawed in water bath at 37 °C for 20-25 min. Approximately 10 mL of plasma from each FFP unit was tested for FII, FVIII, fibrinogen and sterility. The thawed FFP units were then kept at 4 °C for 6 h before being refrozen and stored at - 20 °C. Two weeks later, the refrozen FFP were thawed again and representative samples were analysed as before. There was a significant decline in the mean FVIII level, from 155.77% to 85.6% at second thaw. The mean FII level increased significantly from 74.9% to 82%, whereas the mean fibrinogen level fell from 3.34g/L to 3.28 g/L, but the decline was not statistically significant. There was no bacterial contamination in all samples at both time points. Refrozen plasma may be considered as an alternative to the storage of thawed unused FFP provided they are kept in a controlled environment to reduce wastage. These thawed refrozen FFP can be used later in bleeding cases like other FFP as the levels of FVIII are still within the standard haematology range (0.5-2 IU/mL) and above the minimal level of 30% coagulation factors required for adequate haemostasis.

Evaluation of Coagulation Factors Activity in Different Types of Plasma Preparations

Fresh frozen plasma (FFP) is a crucial substitute therapy in management of bleeding; producing plasma from whole blood stored within 24 h offers operational flexibility and leukocyte filtration significantly reduce transfusion reactions, it is necessary to consider the impact of these plasma preparations on clotting factors activity. Total of 75 plasma samples collected from 25 blood donors distributed as 3 groups; FFP (Group A), leukocyte filtrated FFP (Group B) and plasma frozen within 24 h i.e. PF24 (Group C), for all samples prothrombin time (PT), INR, (APTT), Factors V, VII, VIII, IX levels and Fibrinogen were done, also comparing coagulation factors levels in FFP in different blood groups. There were significant difference between three groups in (PT), INR and (APTT): (P = 0.00). Concerning Factor VII: significant difference (P = 0.03) between the three groups, FFP had a significantly higher level of FVII compared to filtrated FFP (98.92 vs. 82.52%; P = 0.02), while no significant difference between FFP and PF24 was detected (P = 0.76). Factor VIII: had significant difference (P = 0.00) between the three groups, FFP and Filtrated FFP had no significant difference regarding level of FVIII (P = 0.72), but FFP had significantly higher level of FVIII compared to PF24 (P < 0.05). Concerning Fibrinogen level: no significant difference between FFP and filtrated FFP (P = 0.99), while FFP had a higher level versus PF24 (P < 0.05). On the Contrary, no significant difference between three groups in Factor V: (P = 0.22) and Factor IX: (P = 0.12). ABO blood group effect on studied parameters in FFP: FVIII was statistically higher in Non-O blood group (P = 0.03), other factors had no statistical differences (P > 0.05). The leukocyte filtration of FFP did not affect the majority of coagulation factors activities, although FVII level was reduced, it stills enough for surgical hemostasis. The PF24 resulted in reduced FVIII and fibrinogen levels but no significant changes in FV, FVII or FIX, thus, can be used for FFP indications except that specifically requiring replacement of FVIII and/or fibrinogen as Hemophilia or DIC. No significant difference in coagulation factors of FFP between O and non-O blood groups except FVIII that was reduced in O blood group.

Plasma Transfusion: History, Current Realities, and Novel Improvements

Traumatic hemorrhage is the leading cause of preventable death after trauma. Early transfusion of plasma and balanced transfusion have been shown to optimize survival, mitigate the acute coagulopathy of trauma, and restore the endothelial glycocalyx. There are a myriad of plasma formulations available worldwide, including fresh frozen plasma, thawed plasma, liquid plasma, plasma frozen within 24 h, and lyophilized plasma (LP). Significant equipoise exists in the literature regarding the optimal plasma formulation. LP is a freeze-dried formulation that was originally developed in the 1930s and used by the American and British military in World War II. It was subsequently discontinued due to risk of disease transmission from pooled donors. Recently, there has been a significant amount of research focusing on optimizing reconstitution of LP. Findings show that sterile water buffered with ascorbic acid results in decreased blood loss with suppression of systemic inflammation. We are now beginning to realize the creation of a plasma-derived formulation that rapidly produces the associated benefits without logistical or safety constraints. This review will highlight the history of plasma, detail the various types of plasma formulations currently available, their pathophysiological effects, impacts of storage on coagulation factors in vitro and in vivo, novel concepts, and future directions.

Quality Assessment of Established and Emerging Blood Components for Transfusion

Blood is donated either as whole blood, with subsequent component processing, or through the use of apheresis devices that extract one or more components and return the rest of the donation to the donor. Blood component therapy supplanted whole blood transfusion in industrialized countries in the middle of the twentieth century and remains the standard of care for the majority of patients receiving a transfusion. Traditionally, blood has been processed into three main blood products: red blood cell concentrates; platelet concentrates; and transfusable plasma. Ensuring that these products are of high quality and that they deliver their intended benefits to patients throughout their shelf-life is a complex task. Further complexity has been added with the development of products stored under nonstandard conditions or subjected to additional manufacturing steps (e.g., cryopreserved platelets, irradiated red cells, and lyophilized plasma). Here we review established and emerging methodologies for assessing blood product quality and address controversies and uncertainties in this thriving and active field of investigation.

The effect of centrifugation at various g force levels on rheological properties of rat, dog, pig and human red blood cells

Laboratory investigations often require centrifugation of blood samples for various erythrocyte tests. Although there is a lack of data about the effect of centrifugation at various g force levels on erythrocyte rheological properties. We aimed to investigate the effect of a 10-minute centrifugation at 500, 1000 or 1500 g at 15°C of rat, dog, pig and human venous (K3-EDTA, 1.5 mg/ml) blood samples. Hematological parameters, erythrocyte deformability, cell membrane stability, osmotic gradient ektacytometry (osmoscan) and erythrocyte aggregation were determined. Hematological and erythrocyte deformability parameters showed interspecies differences, centrifugation caused no significant alterations. Cell membrane stability for human erythrocytes centrifuged at higher g level showed less decrease in deformability. Osmoscan O min parameter showed slight elevation in dog centrifuged aliquots. Erythrocyte aggregation parameters changed unexpectedly. Rat and dog erythrocyte aggregation indices significantly dropped in centrifuged aliquots. Pig erythrocyte aggregation indices increased significantly after centrifugation. Human erythrocyte aggregation was the most stable one among the investigated species. The used centrifugation protocols caused the largest alterations in erythrocyte aggregation in a controversial way among the investigated species. On the other hand, erythrocyte deformability parameters were stable, cell membrane stability and osmoscan data show minor shifts.

Determining the effect of storage conditions on prothrombin time, activated partial thromboplastin time and fibrinogen concentration in rat plasma samples

Coagulation parameters are usually included in clinical and preclinical safety studies to evaluate the effect of xenobiotics on the extrinsic or intrinsic pathways of coagulation. The analysis is generally performed at the time of terminal sacrifice where many activities are scheduled. Chances of delay in analysis are likely particularly when blood is collected for coagulation via the abdominal vena cava. This experiment was planned to assess the variations in coagulation parameters caused by delay in analysis as well as by storage conditions. Blood was collected from the posterior vena cava under isoflurane anesthesia, and the plasma was separated immediately. Coagulation parameters were evaluated at 0, 6, 24 and 48 h from the plasma stored at room temperature, as well as plasma stored under refrigerated and freezing conditions. Stability of the analytes in blood was also evaluated under refrigerated conditions for 6 h. All parameters were analyzed using a semi-automated coagulometer. Prothrombin time (PT) was stable under all three storage conditions for up to 6 h. Although statistically significant differences were observed for activated partial thromboplastin time (APTT) at room and refrigeration temperatures for up to 6 h, the difference was clinically non-relevant. Fibrinogen was found to be the most stable parameter that showed consistency in results even up to 48 h under all three storage conditions. Plasma for PT can be stored and analyzed without any significant changes for up to 6 h from the actual blood collection, while fibrinogen level testing can be extended for up to 48 h after collection under any storage condition. For reliable APTT results, plasma samples should be run immediately after collection.

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.

Influence of Storage Time and Temperature on International Normalized Ratio (INR) Levels and Plasma Activities of Vitamin K Dependent Clotting Factors

We designed this study to assess the effect of storage time and temperature on the international normalized ratio (INR) levels and plasma activities of vitamin K-dependent, clotting factors. A total of 100 subjects, comprising 34 healthy controls, 33 patients with liver cirrhosis and 33 patients on long-term coumarin therapy were enrolled. After centrifugation of collected specimens, aliquots of plasma were stored at room temperature (20 -22 degrees C), refrigerated at 2-6 degrees C and frozen at -40 degrees C. Determinations of INR and plasma activities of clotting factors II, VII, IX and X were performed immediately after sampling (0 time) and after 6, 12 and 24 h. We found no significant change of either INR levels or plasma activity of any of the studied clotting factors up-to 24 h at different studied temperatures (p >0.05). Our data demonstrates that clinical specimens for determination of INR levels and plasma activities of factors II, VII, IX and X are acceptable for testing for up-to 24 h whatever may be the temperature of storage.

An emergency department thawed plasma protocol for severely injured patients

IMPORTANCE

In an effort to expedite delivery of plasma for patients requiring massive transfusions, US medical centers began keeping thawed plasma (TP) in their blood banks (BBs), markedly reducing time to release of plasma; however, the time to transfusion was still excessively long.

OBJECTIVE

To expedite delivery and transfusion of TP through implementation of an emergency department (ED) protocol.

DESIGN AND SETTING

Retrospective cohort study in an American College of Surgeons-verified level I trauma center.

PARTICIPANTS

Using the Trauma Registry of the American College of Surgeons database, we evaluated all adult trauma patients admitted from June 1, 2009, through August 31, 2010, who arrived directly from the scene, were the institution's highest level trauma activation, and received at least 1 U of red blood cells and 1 U of plasma in the first 6 hours after admission. The protocol was initiated in February 2010 by giving 4 U of AB plasma to patients in the ED. Patients were then divided into 2 groups: those admitted 8 months before (TP-BB) and 8 months after implementing TP location change (TP-ED).

MAIN OUTCOME MEASURES

Primary outcome was time to first unit of plasma. Secondary outcomes included 24-hour blood use and 24-hour and 30-day mortality.

RESULTS

A total of 294 patients met the study criteria (130 in the TP-BB group and 164 in the TP-ED). Although the patient demographics were similar, TP-ED patients had greater anatomical injury (median Injury Severity Score, 18 vs 25; P = .02) and more physiologic disturbances (median weighted Revised Trauma Score, 6.81 vs 3.83; P = .008). The TP-ED patients had a shorter time to first plasma transfusion (89 vs 43 minutes, P < .001). The TP-ED protocol was associated with a reduction in 24-hour transfusion of RBCs (P = .04), plasma (P = .04), and platelets (P < .001). Logistic regression identified TP-ED as an independent predictor of decreased 30-day mortality (odds ratio, 0.43; 95% CI, 0.194-0.956; P = .04).

CONCLUSIONS

We demonstrated that implementation of an ED-TP protocol expedites transfusion of plasma to severely injured patients. This approach is associated with a reduction in overall blood product use and a 60% decreased odds in 30-day mortality.

The effect of repeated freezing and thawing on levels of vitamin K-dependent coagulation factors and fibrinogen in fresh frozen plasma

Background:

Fresh frozen plasma (FFP) is considered adequate for transfusion immediately after thawing or for up to 24 hours if kept at 1–6°C, and is currently used very often to replace deficient clotting factors. If factor levels in refrozen FFP are within normal limits, then this component can possibly be transfused, thus avoiding wastage of FFP.

Aim:

To study the fate of vitamin K-dependent coagulation factors (F II, F VII, F IX, F X) and fibrinogen activity levels in repeatedly (twice) frozen and thawed FFP.

Materials and Methods:

Two hundred FFP units comprising 50 units of each major blood group (A, B, AB, and O) were thawed at 37°C and 10–20 mL of FFP transferred to transfer bags with the help of a sterile connecting device (SCD). The FFP samples were taken into tubes (first sampling), and then the transfer bags were kept for 24 hours at 4°C. After 24 hours, repeat samples were taken in tubes from the transfer bag (second sampling), and then the bags were re-stored at < -18°C. One week later, the above procedure was repeated. Activity of coagulation factors and fibrinogen levels were measured by the automated coagulation analyzer.

Results:

The levels of F II, F VII, F IX, F X, and fibrinogen of all the 200 FFP units, at all four time points, were above the lower normal value, but well within the normal range.

Conclusion:

The levels of F II, F VII, F IX, F X, and fibrinogen remain stable and adequate for transfusion in twice-thawed-and-refrozen FFP. This component can be safely used for transfusion as a source of vitamin K-dependent clotting factors and fibrinogen.

Protein C activity in dogs: adaptation of a commercial human colorimetric assay and evaluation of effects of storage time and temperature

Objectives of this study were to adapt a commercial human protein C (PC) colorimetric assay for use in dogs and to investigate effects of various storage conditions. The human assay was modified by using pooled canine plasma for calibration and by increasing the activation time. PC activity was measured in fresh canine plasma and in plasma stored under various conditions. PC activity of some stored samples was significantly different from that of fresh plasma; however, differences were small. No difference was detected in samples stored under similar conditions but analyzed in different laboratories using similar methodology. Results of this study indicate that the human colorimetric assay is suitable for canine samples if pooled canine plasma is used for calibration, that Clinical and Laboratory Standards Institute sample storage guidelines developed for testing in humans are appropriate for dogs, and that comparisons of results from laboratories using similar methodology are legitimate.

Evaluation of the properties of components prepared and stored after holding of whole blood units for 8 and 24 hours at ambient temperature

BACKGROUND

The capability of holding whole blood (WB) units at ambient temperature, overnight, should help in platelet (PLT) concentrate preparation logistics. We summarize the results of a study conducted in the early 1990s that compared, in particular, PLT and red blood cell (RBC) in vivo viability properties following storage after preparation after 8- and 24-hour WB hold periods.

STUDY DESIGN AND METHODS

Individuals donated units of WB on two occasions. Centrifugation at 20 to 24°C to separate PLTs and additive system RBC placement at 1 to 6°C was completed 8 hours after phlebotomy or after 24 hours in randomized order. Components were not leukoreduced. Studies including in vitro biochemical and hematologic analyses and autologous in vivo RBC and PLT evaluations were conducted at two sites.

RESULTS

RBC 24-hour in vivo (mean ± SD) recoveries (single-label approach), after 35 days of storage, were 79.2 ± 4.3 and 79.4 ± 3.9% (n = 9; p > 0.05), with WB holding periods of 8 and 24 hours, respectively. With 42 days of storage, recovery after a 24-hour hold was slightly less than with an 8-hour hold (72.9 ± 6.5% vs. 76.0 ± 5.4%; n = 17; p < 0.05). RBC 2,3-diphosphoglycerate acid levels were substantially less after the 24-hour hold compared to after the 8-hour hold (n = 18; p < 0.05). PLT recovery after 5 days of storage with 8- and 24-hour hold periods were similar, 51.1 ± 14.9 and 50.6 ± 17.7%, respectively (n = 18; p > 0.05). The PLT survival variable and in vitro properties reflecting storage quality also showed no significant difference.

CONCLUSION

RBC and PLT in vivo variables, and most in vitro variables, were not significantly different after storage with WB holding times of 8 and 24 hours except for a slight diminution of RBC recovery with the 24-hour hold after 42 days of storage.

Damage Control Resuscitation: From Emergency Department to the Operating Room

Damage control surgery emphasizes limited operations with control of bleeding and contamination. Traditional management centered upon correction of acidosis and hypotension with crystalloids. Damage control resuscitation (DCR) is permissive hypotension and early hemostatic resuscitation combined identified and corrects coagulopathy with fresh-frozen plasma (FFP), restricting use of crystalloids. We hypothesize a survival advantage in patients managed with DCR when compared with a historical cohort of patients. During the 2-year retrospective review, a 1-year period after institution of DCR was compared with a historical control. Resuscitation strategies were analyzed and stratified into emergency department (ED) resuscitation and intraoperative resuscitation. Univariate analysis of continuous data was done with Student's t test followed by multiple logistic regression. Fifty-seven and 61 patients were managed during the Non DCR and DCR periods respectively. Baseline demographic patient characteristics and physiologic variables were similar between groups. ED DCR patients received less crystalloids: 1.1 versus 4.7 liters ( P = 0.0001), more FFP: 1.8 versus 0.5 ( P = 0.001). NonDCR had a lower initial systolic pressure in the operating room when compared with DCR: 81 mm Hg versus 95 mm Hg ( P = 0.03). DCR patients received less intraoperative crystalloids: 5.7 versus 15.8 liters ( P = 0.0001) and more FFP: 15.1 versus 6.2 ( P = 0.0001). DCR conveyed a survival benefit (Odds Ratio; 95% confidence interval: 0.40 (0.18-0.90), P = 0.024). NonDCR group had 13.2 days longer hospital length of stay. Damage control resuscitation, beginning in the ED, used more packed red blood cells and FFP minimizing crystalloids. DCR was associated with a survival advantage and shorter length of stay in patients with severe hemorrhage.

Effect of storage conditions on prothrombin time, activated partial thromboplastin time and fibrinogen concentration on canine plasma samples

The present study was to assess the effect of storage conditions on prothrombin time (PT), activated partial thromboplastin time (aPTT) and fibrinogen concentration in blood samples of healthy dogs. Thirty-five dogs of various breeds were included in the study. Citrated blood samples were obtained and plasma was divided into four aliquots to assess selected clotting parameters by means of a coagulometer. The first aliquot was analysed within 1 h after collection, while the remaining 3 were stored at 8℃ for 4, 8 and 24 h, respectively. One-way repeated measures analysis of variance documented a significant decreasing effect on PT at 24 h compared to 8 h and on fibrinogen concentration after 8 and 24 h compared to sampling time and at 4 and 24 h compared to 8 h post sampling. In conclusion, the results of this study indicate that only fibrinogen appears prone to significant decrease. In fact, aPTT is not substantially affected by refrigeration for at least 24 h post sampling and PT showed a statistical difference that does not necessary indicate biological significance as the results obtained were within reference intervals for the dog.

The how's and why's of evidence based plasma therapy

Although traditionally fresh frozen plasma (FFP) has been the product of choice for reversing a significant coagulopathy, the modern blood bank will have several different plasma preparations which should all be equally efficacious in reversing a significant coagulopathy or arresting coagulopathic bleeding. Emerging evidence suggests that for a stable patient, transfusing plasma for an INR≤1.5 does not confer a hemostatic benefit while unnecessarily exposing the patient to the risks associated with plasma transfusion. This review will discuss the various plasma products that are available and present some of the current literature on the clinical uses of plasma.

Perioperative coagulation management--fresh frozen plasma

Clinical studies support the use of perioperative fresh frozen plasma (FFP) in patients who are actively bleeding with multiple coagulation factor deficiencies and for the prevention of dilutional coagulopathy in patients with major trauma and/or massive haemorrhage. In these settings, current FFP dosing recommendations may be inadequate. However, a substantial proportion of FFP is transfused in non-bleeding patients with mild elevations in coagulation screening tests. This practice is not supported by the literature, is unlikely to be of benefit and unnecessarily exposes patients to the risks of FFP. The role of FFP in reversing the effects of warfarin anticoagulation is dependent on the clinical context and availability of alternative agents. Although FFP is commonly transfused in patients with liver disease, this practice needs broad reconsideration. Adverse effects of FFP include febrile and allergic reactions, transfusion-associated circulatory overload and transfusion-related acute lung injury. The latter is the most serious complication, being less common with the preferential use of non-alloimmunised, male-donor predominant plasma. FP24 and thawed plasma are alternatives to FFP with similar indications for administration. Both provide an opportunity for increasing the safe plasma donor pool. Although prothrombin complex concentrates and factor VIIa may be used as alternatives to FFP in a variety of specific clinical contexts, additional study is needed.

Clinical review: Fresh frozen plasma in massive bleedings - more questions than answers

Fresh frozen plasma (FFP) is indicated for the management of massive bleedings. Recent audits suggest physician knowledge of FFP is inadequate and half of the FFP transfused in critical care is inappropriate. Trauma is among the largest consumers of FFP. Current trauma resuscitation guidelines recommend FFP to correct coagulopathy only after diagnosed by laboratory tests, often when overt dilutional coagulopathy already exists. The evidence supporting these guidelines is limited and bleeding remains a major cause of trauma-related death. Recent studies demonstrated that coagulopathy occurs early in trauma. A novel early formula-driven haemostatic resuscitation proposes addressing coagulopathy early in massive bleedings with FFP at a near 1:1 ratio with red blood cells. Recent retrospective reports suggest such strategy significantly reduces mortality, and its use is gradually expanding to nontraumatic bleedings in critical care. The supporting studies, however, have bias limiting the interpretation of the results. Furthermore, logistical considerations including need for immediately available universal donor AB plasma, short life after thawing, potential waste and transfusion-associated complications have challenged its implementation. The present review focuses on FFP transfusion in massive bleeding and critically appraises the evidence on formula-driven resuscitation, providing resources to allow clinicians to develop informed opinion, given the current deficient and conflicting evidence.

Gewinnung, Herstellung und Lagerung von Blut und Blutkomponenten

Blutspender leisten einen wertvollen Dienst für die Gemeinschaft: Die ständige Verfügbarkeit von Blutkomponenten ist zur unverzichtbaren Voraussetzung für viele Bereiche der Medizin geworden. Nicht nur die Gewinnung und Aufarbeitung von Blut und Blutbestandteilen zur Sicherstellung einer qualitativ wie quantitativ guten Versorgung, sondern auch die kompetente Betreuung der Spender ist eine der großen Aufgaben der Transfusionsmedizin.

Instituting a thawed plasma procedure: it just makes sense and saves cents

BACKGROUND

The objectives of this time-series study were to elucidate the impact of a thawed plasma standard operating procedure (TP SOP) on plasma wastage and on cost savings.

STUDY DESIGN AND METHODS

This study compared plasma wastage for 1 year before versus 1 year after implementation of a TP SOP.

RESULTS

The plasma wastage and discard declined 79.7 and 64.9%, respectively, with a cost savings of $15,654.79 during the 1 year after implementation of the TP SOP. The risk that a unit of plasma would be wasted decreased 86.2% from Year 1 to Year 2 and the risk that a unit of plasma would be discarded decreased 76.3% from Year 1 to Year 2.

CONCLUSION

Our study showed the positive, sustained, impact of implementing a TP SOP. Twelve months after introducing the SOP our Blood Bank and Transfusion Medicine Services' plasma wastage and discard were dramatically reduced, saving thousands of dollars. Initiating a TP SOP just makes sense; it is easy to implement, conserves plasma, and saves cents.

Scientific aspects of supplying blood to distant military theaters

PURPOSE OF REVIEW

Reduction in combat zone morbidity and mortality requires rapid delivery of safe blood products as an integral element of advanced trauma surgical care. This review of the current literature presents scientific aspects of supplying blood for rapid delivery to enhance survival and patient outcome in the combat zone.

RECENT FINDINGS

Most deaths due to hemorrhage can be averted by transfusion during the first hour from injury; therefore, maintaining a dependable inventory of blood products in combat support hospitals is essential. Current casualty care in distant geographic locations involves rapid air evacuation to combat support hospitals or fleet hospitals, where massive transfusions may be required. Resuscitation by forward surgical teams utilizing red blood cells before air evacuation or in-flight has also been reported. To improve survival, these massive transfusions should be composed of not only red blood cells but also other blood components and plasma factors.

SUMMARY

Rapid on-site combat casualty transfusion support requires specialized blood transport containers and transfusion practices not observed in noncombat settings, such as the mobile walking blood bank and a frozen blood program. Additionally, technology for improved transport containers, cell-free hemoglobin-based oxygen carriers, freeze-dried blood, and recombinant activated coagulation factor has attracted focused interest.

Nonsurgical bleeding diathesis in anemic thrombocytopenic patients: role of temperature, red blood cells, platelets, and plasma-clotting proteins

Research at the Naval Blood Research Laboratory (Boston, MA) for the past four decades has focused on the preservation of red blood cells (RBCs), platelets (PLTs), and plasma-clotting proteins to treat wounded servicemen suffering blood loss. We have studied the survival and function of fresh and preserved RBCs and PLTs and the function of fresh and frozen plasma-clotting proteins. This report summarizes our peer-reviewed publications on the effects of temperature, RBCs, PLTs, and plasma-clotting proteins on the bleeding time (BT) and nonsurgical blood loss. The term nonsurgical blood loss refers to generalized, systemic bleeding that is not corrected by surgical interventions. We observed that the BT correlated with the volume of shed blood collected at the BT site and to the nonsurgical blood loss in anemic thrombocytopenic patients after cardiopulmonary bypass surgery. Many factors influence the BT, including temperature; hematocrit (Hct); PLT count; PLT size; PLT function; and the plasma-clotting proteins factor (F)VIII, von Willebrand factor, and fibrinogen level. Our laboratory has studied temperature, Hct, PLT count, PLT size, and PLT function in studies performed in non-aspirin-treated and aspirin-treated volunteers, in aspirin-treated baboons, and in anemic thrombocytopenic patients. This monograph discusses the role of RBCs and PLTs in the restoration of hemostasis, in the hope that a better understanding of the hemostatic mechanism might improve the treatment of anemic thrombocytopenic patients. Data from our studies have demonstrated that it is important to transfuse anemic thrombocytopenic patients with RBCs that have satisfactory viability and function to achieve a Hct level of 35 vol percent before transfusing viable and functional PLTs. The Biomedical Excellence for Safer Transfusion (BEST) Collaborative recommends that preserved PLTs have an in vivo recovery of 66 percent of that of fresh PLTs and a life span that is at least 50 percent that of fresh PLTs. Their recommendation does not include any indication that preserved PLTs must be able to function to reduce the BT and reduce or prevent nonsurgical blood loss. One of the hemostatic effects of RBC is to scavenge endothelial cell nitric oxide, a vasodilating agent that inhibits PLT function. In addition, endothelin may be released from endothelial cells, a potent vasoconstrictor substance,to reduce blood flow at the BT site. RBCs, like PLTs at the BT site, may provide arachidonic acid and adenosine diphosphate to stimulate the PLTs to make thromboxane, another potent vasoconstrictor substance and a PLT-aggregating substance. At the BT site, the PLTs and RBCs are activated and phosphatidyl serine is exposed on both the PLTs and the RBCs. FVa and FXa, which generate prothrombinase activity to produce thrombin, accumulate on the PLTs and RBCs. A Hct level of 35 vol percent at the BT site minimizes shear stress and reduces nitric oxide produced by endothelial cells. The transfusion trigger for prophylactic PLT transfusion should consider both the Hct and the PLT count. The transfusion of RBCs that are both viable and functional to anemic thrombocytopenic patients may reduce the need for prophylactic leukoreduced PLTs, the alloimmunization of the patients, and the associated adverse events related to transfusion-related acute lung injury. The cost for RBC transfusions will be significantly less than the cost for the prophylactic PLT transfusions.

Stability of activated partial thromboplastin time (APTT) test under different storage conditions

We designed this study to assess the effect of storage time and temperature on the activated partial thromboplastin time (APTT) test and plasma activity of factor VIII (FVIII). A total of 71 subjects, comprising 34 healthy controls and 37 patients receiving unfractionated heparin were enrolled. After centrifugation of collected specimens aliquots of plasma were stored at room temperature (20-22 degrees C), refrigerated at 2-6 degrees C and frozen at - 40 degrees C. Determination of APTT and plasma activity of FVIII were performed immediately after sampling (zero time) and after 6, 12 and 24 h. We found no significant difference in APTT after 6 h at room temperature and 4 degrees C compared to zero time values (P>0.05) in control group, while APTT was significantly changed at other storage conditions. With regard APTT test in patients on heparin therapy and samples for FVIII activity in healthy subjects; there was a statistically significant change in their results after 6, 12 and 24 h at room temperature, 4 and - 40 degrees C compared to zero time value(P < 0.05). Our data demonstrate that the APTT test can be done within 6 h when stored at room temperature and 4 degrees C without change in the result in healthy subjects. APTT test in patients on heparin therapy and samples for FVIII test in healthy subjects must be done immediately and without delay to avoid reduction in their activities.