Hemostatic characteristics of thawed, pooled cryoprecipitate stored for 35 days at refrigerated and room temperatures

Potential for prolongation of fibrinogen concentrates post-reconstitution

BACKGROUND AND OBJECTIVES

Reconstituted fibrinogen concentrate is considered stable for 8-24 h based on product monographs. Given the long half-life of fibrinogen in vivo (3-4 days), we hypothesized that reconstituted sterile fibrinogen protein would remain stable longer than 8-24 h. Extending the expiry date for reconstituted fibrinogen concentrate could decrease wastage and facilitate reconstitution in advance to minimize turnaround times. We performed a pilot study to define the stability of reconstituted fibrinogen concentrates over time.

MATERIALS AND METHODS

Reconstituted Fibryga® (Octapharma AG) from 64 vials was stored in the temperature-controlled refrigerator (4 °C) for up to 7 days with functional fibrinogen concentration measured serially using the automated Clauss method. The samples were frozen, then thawed and diluted with pooled normal plasma in order for them to be batch tested.

RESULTS

Reconstituted fibrinogen samples stored in the refrigerator showed no significant reduction in functional fibrinogen concentration for the entire 7-day study period (p = 0.63). Duration of initial freezing had no detrimental effect on functional fibrinogen levels (p = 0.23).

CONCLUSION

Fibryga® can be stored at 2-8 °C post-reconstitution for up to one week with no loss in functional fibrinogen activity based on Clauss fibrinogen assay. Further studies with other fibrinogen concentrate formulations and clinical in vivo studies may be warranted.

Determining transfusion use in major burn patients: A retrospective review and analysis from 2009 to 2019

Blood transfusion is an important treatment for patients with major burns. Understanding the predictive factors of blood product usage in major burns can improve effective transfusion therapy. We retrospectively reviewed the medical records of the Burn Center, First Affiliated Hospital of the Chinese Naval Military Medical University, from August 2009 to July 2019 and enrolled all patients with major burns treated in that decade. Basic information, condition, and blood-transfusion details of the patients were analyzed to identify predictive factors for blood use and prognosis. Despite a yearly decreasing trend, the frequency of use of blood-product usage in major burns was high at 57.72%, with 5.39 times and 28.76 units of blood usage per person. Burn area was the most important predictive factor for blood transfusion at different stages. Burn depth, combined with injury, age, and other factors, affected blood use. Blood use or volume correlated with prognosis; especially, platelet and cryoprecipitate use was significantly associated with increased mortality. Blood product usage in major burns patients is related not only to the clinical condition, but also to doctors' experience, which can predict prognosis. Blood use is associated with increased mortality, although we found no evidence of a causal association.

Early cryoprecipitate transfusion versus standard care in severe postpartum haemorrhage: a pilot cluster-randomised trial

There is a lack of evidence evaluating cryoprecipitate transfusion in severe postpartum haemorrhage. We performed a pilot cluster‐randomised controlled trial to evaluate the feasibility of a trial on early cryoprecipitate delivery in severe postpartum haemorrhage. Pregnant women (>24 weeks gestation), actively bleeding within 24 h of delivery and who required at least one unit of red blood cells were eligible. Women declining transfusion in advance or with inherited clotting deficiencies were not eligible. Four UK hospitals were randomly allocated to deliver either the intervention (administration of two pools of cryoprecipitate within 90 min of first red blood cell unit requested plus standard care), or the control group treatment (standard care, where cryoprecipitate is administered later or not at all). The primary outcome was the proportion of women who received early cryoprecipitate (intervention) vs. standard care (control). Secondary outcomes included consent rates, acceptability of the intervention, safety outcomes and preliminary clinical outcome data to inform a definitive trial. Between March 2019 and January 2020, 199 participants were recruited; 19 refused consent, leaving 180 for analysis (110 in the intervention and 70 in the control group). Adherence to assigned treatment was 32% (95%CI 23–41%) in the intervention group vs. 81% (95%CI 70–90%) in the control group. The proportion of women receiving cryoprecipitate at any time‐point was higher in the intervention (60%) vs. control (31%) groups; the former had fewer red blood cell transfusions at 24 h (mean difference −0.6 units, 95%CI −1.2 to 0); overall surgical procedures (odds ratio 0.6, 95%CI 0.3–1.1); and intensive care admissions (odds ratio 0.4, 95%CI 0.1–1.1). There was no increase in serious adverse or thrombotic events in the intervention group. Staff interviews showed that lack of awareness and uncertainty about study responsibilities contributed to lower adherence in the intervention group. We conclude that a full‐scale trial may be feasible, provided that protocol revisions are put in place to establish clear lines of communication for ordering early cryoprecipitate in order to improve adherence. Preliminary clinical outcomes associated with cryoprecipitate administration are encouraging and merit further investigation.

Lower Mortality with Cryoprecipitate During Massive Transfusion in Penetrating but Not Blunt Trauma

BACKGROUND

Balanced blood product transfusion improves the outcomes of trauma patients with exsanguinating hemorrhage, but it remains unclear whether administering cryoprecipitate improves mortality. We aimed to examine the impact of early cryoprecipitate transfusion on the outcomes of the trauma patients needing massive transfusion (MT).

METHODS

All MT patients 18 years or older in the 2017 Trauma Quality Improvement Program (TQIP) were retrospectively reviewed. MT was defined as the transfusion of ≥10 units of blood within 24 hours. Propensity score analysis (PSA) was used to 1:1 match then compare patients who received and those who did not receive cryoprecipitate in the first 4 hours after injury. Outcomes included in-hospital mortality, 1-day mortality, in-hospital complications and transfusion needs at 24 hours.

RESULTS

Of 1,004,440 trauma patients, 1,454 MT patients received cryoprecipitate and 2,920 did not. After PSA, 877 patients receiving cryoprecipitate were matched to 877 patients who did not. In-hospital mortality was lower among patients who received cryoprecipitate (49.4% v. 54.9%, P = 0.022), as was 1-day mortality. Sub-analyses showed that mortality was lower with cryoprecipitate in patients with penetrating (37.5% versus. 48%, adjusted P = 0.008), but not blunt trauma (58.5% versus. 59.8%, adjusted P = 1.000). In penetrating trauma, the cryoprecipitate group also had lower 1-day mortality (21.8% versus. 38.6%, P <0.001) and a higher rate of hemorrhage control surgeries performed within 24 hours (71.4% versus. 63.3%, P = 0.018).

CONCLUSIONS

Cryoprecipitate in MT is associated with improved survival in penetrating, but not blunt, trauma. Randomized trials are needed to better define the role of cryoprecipitate in MT.

Pro-Con Debate: Fibrinogen Concentrate or Cryoprecipitate for Treatment of Acquired Hypofibrinogenemia in Cardiac Surgical Patients

Cryoprecipitate has been the gold standard for treating acquired hypofibrinogenemia in cardiac surgery for nearly 50 years. More recently, fibrinogen concentrate has been used off-label in the United States and is the standard in European countries and Canada to treat the acquired hypofibrinogenemia during cardiac surgery. Fibrinogen concentrate has multiple potential advantages including rapid reconstitution, greater dose predictability, viral inactivation during processing, and reduced transfusion-related adverse events. However, because fibrinogen concentrate lacks the other components contained in the cryoprecipitate, it may not be the "ideal" product for replacing fibrinogen in all cardiac surgical patients, particularly those with longer cardiopulmonary bypass duration. In this Pro-Con commentary article, we discuss the advantages and disadvantages of using fibrinogen concentrate and cryoprecipitate to treat acquired hypofibrinogenemia in cardiac surgical patients.

Stability of Reconstituted Fibrinogen Concentrate in Hemostatic Function and Concentration

INTRODUCTION

Canadian Armed Forces adopted fibrinogen concentrate (RiaSTAP) for hemostatic resuscitation in the far-forward combat setting, given its potential benefits of reducing blood loss, blood transfusion and mortality, and its long storage stability and high portability. The current guidance recommends that RiaSTAP should be administered within 8 hours after reconstitution when stored at room temperature. However, little information about its stability is available. There is also a need to investigate the stability and efficacy of RiaSTAP after reconstitution and exposure to extreme temperatures in which our forces may operate.

MATERIALS AND METHODS

RiaSTAP was reconstituted as per manufacturer's instruction and stored at specific temperatures (-20°C, 4°C, 22°C, 35°C, 42°C, or 50°C) for up to 6 months. Reconstituted RiaSTAP was also oscillated on a rocker at 18 rpm under 22°C and 50°C. Its hemostatic function was measured using rotational thromboelastometry performed with RiaSTAP-spiked whole blood. Fibrinogen concentrations were measured by a commercial enzyme-linked immunosorbent assay (ELISA) kit. Gel electrophoresis was also conducted for initial and stored samples.

RESULTS

We found no change to the hemostatic function of reconstituted RiaSTAP after storage at -20°C for 6 months. At 4°C, no obvious changes to the hemostatic effect of reconstituted RiaSTAP relative to 0 hours were seen until 1,680 hours. At 22°C, a remarkable decrease began after storage for 168 hours. Storage at 35°C significantly decreased the hemostatic effect after 144 hours, while the storage at 42°C resulted in decreased hemostatic function after 72 hours. Finally, storage at 50°C for 8 hours resulted in complete loss of hemostatic function. Compared to the hemostatic activity, the fibrinogen concentration for reconstituted RiaSTAP showed less change over time. No apparent decline in fibrinogen concentration was seen after storage at -20°C for 6 months and at 4°C for 1,680 hours. At 22°C, there were no clear alterations until 792 hours. There was a decline in fibrinogen concentration at 35°C and 42°C after 672 and 600 hours of storage, respectively. At 50°C, little amount of fibrinogen was detected by ELISA at 8 hours. Similar changes in the hemostatic effect and fibrinogen concentration over time were observed under the rocking condition in comparison with the static condition at the same temperature. The gel electrophoresis confirmed fibrinogen degradation which increased with storage temperature and time.

CONCLUSIONS

The stability of reconstituted RiaSTAP decreases with increasing storage temperature. The hemostatic function deteriorated before fibrinogen concentration and integrity were significantly altered at all temperatures for the study period except at 50°C where there was a rapid decline in both hemostatic function and fibrinogen concentration. Sample oscillation did not significantly affect its stability. The shelf life of reconstituted RiaSTAP may, therefore, be recommended accordingly when stored at different temperatures and extended to 6 days at room temperature provided that sterility is maintained.

Extending the post-thaw viability of cryoprecipitate

BACKGROUND

Cryoprecipitate has a short post-thaw expiry time of 6 h. The aim of this study was to assess the stability and function of cryoprecipitate components (FVIII, fibrinogen, vWF, and FXIII) and cryoprecipitate sterility up to 120 h post-thawing when stored at two temperatures (2-6°C and room temperature [20-24°C]).

METHODS AND MATERIALS

Twenty batches (110 individual units) of time-expired, thawed cryoprecipitate were collected. Units were sampled at the 6-h expiration mark and then stored at 2-6°C or room temperature (RT). They were resampled every 24 h for 120 h. One unit from each batch was sent for sterility testing at 120 h. Samples had FVIII (one stage and chromogenic), fibrinogen, FXIII, vWFag, and vWF:RCo assays performed in batches. Rotational thromboelastometry (ROTEM) was also performed.

RESULTS

FVIII levels declined significantly at 120 h post-thawing at both RT and 2-6°C, but still met international standards for FVIII content. Fibrinogen, vWF antigen, and FXIII levels reduced minimally over 120 h and always met international standard requirements when stored at either temperature. ROTEM analysis demonstrated that fibrinogen function was not compromised at 120 h post-thawing under both storage conditions. vWF:RCo levels declined significantly over 120 h at both storage temperatures. No bacterial contamination was detected in 20 units of cryoprecipitate following storage for 120 h post-thawing.

CONCLUSION

These results demonstrate that extension of the storage time of thawed cryoprecipitate to 120 h, stored at either 2-6°C or RT, is feasible while still maintaining required FVIII, fibrinogen, and vWFag levels. Storage at 2-6°C has the advantage of reduced risk of potential bacterial contamination.

Which is the preferred blood product for fibrinogen replacement in the bleeding patient with acquired hypofibrinogenemia-cryoprecipitate or fibrinogen concentrate?

The importance of the targeted treatment of acquired hypofibrinogenemia during hemorrhage with a concentrated fibrinogen product (either cryoprecipitate or fibrinogen concentrate) cannot be underestimated. Fibrinogen concentrate is a pathogen inactivated, pooled product that offers a highly purified single factor concentrate. Cryoprecipitate is a pooled product that comes with a spectrum of other coagulation factors which may further enhance (additional procoagulant effect) or even disturb (prothrombotic risk) hemostasis. The pros and cons of each product are discussed.

Recent advances in use of fresh frozen plasma, cryoprecipitate, immunoglobulins, and clotting factors for transfusion support in patients with hematologic disease

Hematologic diseases include a broad range of acquired and congenital disorders, many of which affect plasma proteins that control hemostasis and immune responses. Therapeutic interventions for these disorders include transfusion of plasma, cryoprecipitate, immunoglobulins, or convalescent plasma-containing therapeutic antibodies from patients recovering from infectious diseases, as well as concentrated pro- or anticoagulant factors. This review will focus on recent advances in the uses of plasma and its derivatives for patients with acquired and congenital hematologic disorders.