Cryoprecipitate: The Current State of Knowledge

Prophylactic cryoprecipitate transfusion in patients undergoing scoliosis surgery: A randomised-controlled trial

BACKGROUND

Scoliosis surgeries in adults often have a high risk of massive blood loss and significant transfusion of blood products during and after surgery. It is not known whether early cryoprecipitate therapy is useful in reducing blood loss and transfusion requirements. The objective of this randomised, prospective placebo control study was to evaluate whether prophylactic administration of cryoprecipitate would reduce blood loss and transfusion requirements during scoliosis surgery.

METHODS

Eighty adult patients scheduled to undergo elective scoliosis correction were randomly assigned to receive either ten units of cryoprecipitate before incision (cryo group) or an equivalent volume of 0.9% saline (placebo group). Blood loss, transfusion requirements, coagulation parameters and complications were assessed.

RESULTS

No significant differences were found in the volume of transfused blood products, intraoperative estimated blood loss between the intervention and placebo groups. Postoperative blood loss was significantly lower in the cry group when compared to the other group. During adult surgical correction of scoliosis, prophylactic administration of cryoprecipitate did not diminish the amount of transfused blood products or decrease intraoperative blood loss.

CONCLUSION

It could be concluded that the prophylactic administration of cryoprecipitate shows no differences in intraoperative blood loss and transfusion requirements during scoliosis surgery.

Clinical Profile of Congenital Factor XIII Deficiency in Children

OBJECTIVES

Congenital Factor 13 Deficiency (FXIIID) is a rare bleeding disorder (RBD) of autosomal recessive inheritance, with an incidence of 1 in 3-5 million. The clinical symptomatology, diagnosis, and management of FXIIID are described.

METHODS

A retrospective chart review of children with FXIIID was performed from January 2000 through October 2021 at a tertiary care center in Southern India. The diagnosis was performed by the Urea clot solubility test (UCST) and Factor XIII antigen assay.

RESULTS

Twenty children (representing 16 families) were included. Male: Female ratio was 1.5:1. The median age of symptom onset was 6 mo, and the median age of diagnosis was 1 y, demonstrating a delay in diagnosis. Consanguinity was present in 15 (75%) with 4 children having affected siblings. Clinical symptomatology ranged from mucosal bleeds to intracranial bleeds and hemarthrosis, with many children having a history of prolonged umbilical bleeding in their neonatal period. Fourteen children were on cryoprecipitate prophylaxis. Four children had breakthrough bleeds due to irregular prophylaxis, including one intracranial bleed due to a delay in cryoprecipitate prophylaxis during the covid pandemic.

CONCLUSIONS

Congenital FXIIID presents with a wide range of bleeding manifestations. The high prevalence of consanguinity in Southern India can be a cause of FXIIID's high prevalence in this region. There is a propensity for intracranial bleeding with a significant number having this at first presentation. Regular prophylaxis is required and feasible to prevent potentially fatal bleeds.

Perioperative Management of a Frail Patient With Bernard-Soulier Syndrome

Bernard-Soulier syndrome (BSS) is an autosomal recessive inherited bleeding disorder characterized by prolonged bleeding time, thrombocytopenia, and giant platelets. Patients with BSS are at an increased risk of bleeding, especially during traumatic injury and surgical procedures. The literature on the anesthetic management of patients with BSS is limited. In this report, we detail the successful management of a frail patient with BSS who underwent a major surgical procedure. Despite comprehensive clinical monitoring and an extended pharmacological strategy, a hemorrhagic complication occurred in the later postoperative phase, emphasizing the necessity for continued support and vigilant clinical monitoring due to the ongoing bleeding risk associated with these patients. In this case, a combined strategy involving antifibrinolytics, recombinant factor VII, and platelet transfusions proved effective.

Comparative analysis of hyperfibrinolysis with activated coagulation between amniotic fluid embolism and severe placental abruption

Amniotic fluid embolism (AFE) and placental abruption (PA) are typical obstetric diseases associated with disseminated intravascular coagulation (DIC). AFE is more likely to be complicated with enhanced fibrinolysis than PA. AFE may have an additional mechanism activating fibrinolytic cascade. We aimed to compare the coagulation/fibrinolysis factors among AFE, PA, and peripartum controls. We assessed AFE cases registered in the Japanese AFE Registry, and PA cases complicated with DIC (severe PA) and peripartum controls recruited at our hospital. The following factors in plasma were compared: prothrombin fragment 1 + 2 (PF1 + 2), plasmin α2-plasmin inhibitor complex (PIC), tissue factor (TF), tissue plasminogen activator (tPA), annexin A2 (AnnA2), total thrombin activatable fibrinolysis inhibitor (TAFI) including its activated form (TAFIa), and plasminogen activator inhibitor-type 1 (PAI-1). PF1 + 2 and PIC were markedly increased in both AFE (n = 27) and severe PA (n = 12) compared to controls (n = 23), without significant difference between those disease groups; however, PIC in AFE showed a tendency to elevate relative to PF1 + 2, compared with severe PA. AFE had significantly increased tPA and decreased total TAFI levels compared with severe PA and controls, which might be associated with further plasmin production in AFE and underlie its specific fibrinolytic activation pathway.

Prospective, Randomized Study of Fibrinogen Concentrate Versus Cryoprecipitate for Correcting Hypofibrinogenemia in Cardiac Surgery Patients

OBJECTIVE

Cardiac surgery with cardiopulmonary bypass (CPB) is associated with hypofibrinogenemia and severe bleeding requiring transfusion. Guidelines recommend cryoprecipitate or fibrinogen concentrate (FC) for the treatment of acquired hypofibrinogenemia. This study compared cryoprecipitate and FC for the correction of acquired hypofibrinogenemia and the associated costs.

DESIGN

A single-center, prospective, randomized study evaluating patients with hypofibrinogenemia after cardiac surgery. The primary endpoint was direct treatment cost. Secondary endpoints included the change in fibrinogen level after FC and/or cryoprecipitate dosing.

SETTING

A single-center study in Astana, Kazakhstan.

PARTICIPANTS

Participants who underwent CPB from 2021 to 2022 and developed clinically significant bleeding and hypofibrinogenemia.

INTERVENTIONS

Patients were randomized to receive cryoprecipitate or FC.

MEASUREMENTS AND MAIN RESULTS

Eighty-eight adult patients with acquired hypofibrinogenemia (<2.0 g/L) after CPB were randomized to receive cryoprecipitate (N = 40) or FC (N = 48), with similar demographics between groups. Overall, mean ± SD 9.33 ± 0.94 units (range, 8-10) cryoprecipitate or 1.40 ± 0.49 g (1-2) FC was administered to the 2 groups. From before administration to 24 hours after, mean plasma fibrinogen increased by a mean ± SD of 125 ± 65 and 96 ± 65 mg/dL in the cryoprecipitate and FC groups, respectively. At 48 hours after administration, there was no significant difference in fibrinogen levels between groups. The mean direct cost of treatment with FC was significantly lower than with cryoprecipitate (p < 0.0001): $1,505.06 ± $152.40 and $631.75 ± $223.67 per patient for cryoprecipitate and FC, respectively.

CONCLUSION

Analysis of plasma fibrinogen concentration showed that cryoprecipitate and FC had comparable effectiveness. However, FC is advantageous over cryoprecipitate due to its ease of handling, lower cost, and high purity.

Real-World Experience with a Human Fibrinogen Concentrate: Clinical Data from Adult and Pediatric Patients Requiring Fibrinogen for Bleeding Control and Prevention

Human fibrinogen concentrate (Fibryga) received temporary approval for fibrinogen replacement therapy in France (2017), with subsequent full approval for congenital and acquired hypofibrinogenemia. We evaluated real-world use for on-demand treatment of bleeding and prophylaxis to enhance our knowledge on fibrinogen concentrate as an option for fibrinogen replacement. Data were retrospectively collected from adult and pediatric patients with fibrinogen deficiency. The primary end point was indication for fibrinogen concentrate use; the secondary end point was treatment success for on-demand treatment/perioperative prophylaxis. The study included 150 adult (median age, 62 years; range, 18-94 years) and 50 pediatric (median age, 3 years; range, 0.01-17 years) patients with acquired fibrinogen deficiency. Fibrinogen concentrate was administered to 47.3% for nonsurgical bleeding, 22.7% for surgical bleeding, and 30.0% for perioperative prophylaxis in adult patients, and to 4.0% for surgical bleeding and 96.0% for perioperative prophylaxis in pediatric patients. Cardiac surgeries accounted for 79.5%/75.0% perioperative prophylaxis and 82.4%/100.0% surgical bleeding cases in adult/pediatric patients, respectively. The mean ± standard deviation (SD, median) total fibrinogen doses were 3.06 ± 1.69 g (32.61 mg/kg), 2.09 ± 1.36 g (22.99 mg/kg), and 2.36 ± 1.25 g (29.67 mg/kg) for adult nonsurgical bleeding, surgical bleeding, and perioperative prophylaxis, respectively; doses of 0.75 ± 0.35 g (47.64 mg/kg) and 0.83 ± 0.62 g (55.56 mg/kg) were used for pediatric surgical bleeding and perioperative prophylaxis, respectively. Treatment success was 85.7%/97.1/93.3% in adults and 50.0%/87.5% in pediatrics for nonsurgical bleeding (adults only), surgical bleeding, and perioperative prophylaxis, respectively. Fibrinogen concentrate demonstrated favorable effectiveness and safety across the age groups. This study contributes to evidence supporting fibrinogen concentrate for bleeding control/prevention in real-world clinical practice, particularly for patients with acquired fibrinogen deficiency.

Investigation of the effect of pre-analytical factors on particle concentration and size in cryoprecipitate using nanoparticle tracking analysis

BACKGROUND

Cryoprecipitate is used primarily to replenish fibrinogen levels in patients. Little is known about the presence of micro- or nano-sized particles in cryoprecipitate. Therefore, we aimed to quantify these particles and investigate some pre-analytical considerations.

MATERIALS AND METHODS

Particle concentration and size distribution were determined in 10 cryoprecipitate units by nanoparticle tracking analysis (NTA). The effects of freeze-thawing cryoprecipitate and 0.45 μm filtration with either regenerated cellulose (RC) or polytetrafluoroethylene (PTFE) filters before sample analysis were examined.

RESULTS

Neither the size nor concentration of particles were affected by two freeze/thaw cycles. PTFE filtration, but not RC filtration, significantly reduced particle mean and mode size compared to RC filtration and mode size compared to unfiltered cryoprecipitate. The 10 cryoprecipitate units had an average particle concentration of 2.50 × 1011  ± 1.10 × 1011  particles/mL, a mean particle size of 133.8 ± 7.5 nm and a mode particle size of 107.9 ± 11.1 nm.

CONCLUSION

This study demonstrated that preanalytical filtration of cryoprecipitate units using RC filters was suitable for NTA. An additional freeze/thaw cycle did not impact NTA parameters, suggesting that aliquoting cryoprecipitate units prior to laboratory investigations is suitable for downstream analyses.

Differences in coagulation-relevant parameters: Comparing cryoprecipitate and a human fibrinogen concentrate

BACKGROUND

Variable fibrinogen content within cryoprecipitate makes accurate dosing challenging in patients with coagulopathic bleeding, in addition to pathogen transmission risks associated with its administration. Purified and standardized human fibrinogen concentrates (HFCs) represent reliable alternatives. Full cryoprecipitate characterization is required to inform selection of an appropriate fibrinogen source for supplementation therapy.

METHODS

Extended biochemical comparison of pooled cryoprecipitate and HFC (Fibryga, Octapharma) was performed using commercially available assays to determine levels of variability in cryoprecipitate and HFC. In addition to standard procoagulant factors, measurements included activities of platelet-derived microparticles (PMPs) and plasminogen, and levels of fibrin degradation products.

RESULTS

Cryoprecipitate contains lower fibrinogen levels than HFC (4.83 vs.19.73 g/L; p<0.001), translating to approximately half the amount of fibrinogen per standard cryoprecipitate dose (two pools, pre-pooled from five donations each) vs. HFC (2.14 vs. 3.95 g; p<0.001). Factor XIII (FXIII) levels were also lower in cryoprecipitate vs. HFC (192.17 vs. 328.33 IU/dL; p = 0.002). Levels of procoagulants in cryoprecipitate, such as von Willebrand Factor (VWF) and factor VIII (FVIII), were highly variable, as was PMP activity. A standard cryoprecipitate dose contains significantly higher levels of measured plasminogen and D-dimer fragments than a standard HFC dose.

CONCLUSION

The tested HFC is a more reliable fibrinogen and FXIII source for accurate dosing compared with cryoprecipitate. Cryoprecipitate appears considerably less predictable for bleeding management due to wide variation in pro- and anticoagulation factors, the presence of PMPs, and the potential to elevate VWF and FVIII to prothrombotic levels.

Treatment of Congenital Afibrinogenemia in a Neonate With Critical Pulmonary Stenosis

Fibrinogen deficiencies in neonates can lead to bleeding complications. In this report, we describe a case of congenital afibrinogenemia in a newborn with critical pulmonary stenosis who presented with bilateral cephalohematomas after an uncomplicated delivery. The initial use of cryoprecipitate was followed by administration of fibrinogen concentrate. We estimated a half-life of 24 to 48 hours with the concentrate product. This patient received fibrinogen replacement and had a subsequent successful cardiac repair. The drug's shorter half-life in this neonate contrasts with prior reports of longer half-life in older patients and is important to note in treating future neonatal patients with this diagnosis.

Blood Product Replacement for Postpartum Hemorrhage

Consideration for blood products replacement in postpartum hemorrhage should be given when blood loss exceeds 1.5 L or when an estimated 25% of blood has been lost. In cases of massive hemorrhage, standardized transfusion protocols have been shown to improve maternal morbidity and mortality. Most protocols recommend a balanced transfusion involving a 1:1:1 ratio of packed red blood cells, platelets, and fresh frozen plasma. Alternatives such as cryoprecipitate, fibrinogen concentrate, and prothrombin complex concentrates can be used in select clinical situations. Although transfusion of blood products can be lifesaving, it does have associated risks.

Cost-effectiveness of Fibrinogen Concentrate vs Cryoprecipitate for Treating Acquired Hypofibrinogenemia in Bleeding Adult Cardiac Surgical Patients

Importance

Excessive bleeding requiring fibrinogen replacement is a serious complication of cardiac surgery. However, the relative cost-effectiveness of the 2 available therapies-fibrinogen concentrate and cryoprecipitate-is unknown.

Objective

To determine cost-effectiveness of fibrinogen concentrate vs cryoprecipitate for managing active bleeding in adult patients who underwent cardiac surgery.

Design, Setting, and Participants

A within-trial economic evaluation of the Fibrinogen Replenishment in Surgery (FIBERS) randomized clinical trial (February 2017 to November 2018) that took place at 4 hospitals based in Ontario, Canada, hospitals examined all in-hospital resource utilization costs and allogeneic blood product (ABP) transfusion costs incurred within 28 days of surgery. Participants included a subset of 495 adult patients from the FIBERS trial who underwent cardiac surgery and developed active bleeding and acquired hypofibrinogenemia requiring fibrinogen replacement.

Interventions

Fibrinogen concentrate (4 g per dose) or cryoprecipitate (10 units per dose) randomized (1:1) up to 24 hours postcardiopulmonary bypass.

Main Outcomes and Measures

Effectiveness outcomes included number of ABPs administered within 24 hours and 7 days of cardiopulmonary bypass. ABP transfusion (7-day) and in-hospital resource utilization (28-day) costs were evaluated and a multivariable net benefit regression model built for the full sample and predefined subgroups.

Results

Patient level costs for 495 patients were evaluated (mean [SD] age 59.2 [15.4] years and 69.3% male.) Consistent with FIBERS, ABP transfusions and adverse events were similar in both treatment groups. Median (IQR) total 7-day ABP cost was CAD $2280 (US dollars [USD] $1697) (CAD $930 [USD $692]-CAD $4970 [USD $3701]) in the fibrinogen concentrate group and CAD $2770 (USD $1690) (IQR, CAD $1140 [USD $849]-CAD $5000 [USD $3723]) in the cryoprecipitate group. Median (interquartile range) total 28-day cost was CAD $38 180 (USD $28 431) $(IQR, CAD $26 350 [USD $19 622]-CAD $65 080 [USD $48 463]) in the fibrinogen concentrate group and CAD $38 790 (USD $28 886) (IQR, CAD $26 180 [USD $19 495]-CAD $70 380 [USD $52 409]) in the cryoprecipitate group. After exclusion of patients who were critically ill before surgery (11%) due to substantial variability in costs, the incremental net benefit of fibrinogen concentrate vs cryoprecipitate was positive (probability of being cost-effective 86% and 97% at $0 and CAD $2000 (USD $1489) willingness-to-pay, respectively). Net benefit was highly uncertain for nonelective and patients with critical illness.

Conclusions and Relevance

Fibrinogen concentrate is cost-effective when compared with cryoprecipitate in most bleeding adult patients who underwent cardiac surgery with acquired hypofibrinogenemia requiring fibrinogen replacement. The generalizability of these findings outside the Canadian health system needs to be verified.

Cryoprecipitate Transfusion After Cardiac Surgery

OBJECTIVES

The association of cryoprecipitate transfusion with patient outcomes after cardiac surgery is unclear. We aimed to investigate the predictors of, and outcomes associated with, postoperative cryoprecipitate transfusion in cardiac surgery patients.

METHODS

We used the Medical Information Mart for Intensive Care III and IV databases. We included adults undergoing cardiac surgery, and propensity score matched cryoprecipitate-treated patients to controls. Using the matched cohort, we investigated the association of cryoprecipitate use with clinical outcomes. The primary outcome was in-hospital mortality. Secondary outcomes were infection, acute kidney injury, intensive care unit length of stay, hospital length of stay, and chest tube output at 2-hour intervals.

RESULTS

Of 12,043 eligible patients, 283 (2.35%) patients received cryoprecipitate. The median dose was 5.83 units (IQR 4.17-7.24) given at a median first transfusion time of 1.75 hours (IQR 0.73-4.46) after intensive care unit admission. After propensity scoring, we matched 195 cryoprecipitate recipients to 743 controls. Postoperative cryoprecipitate transfusion was not significantly associated with in-hospital mortality (odds ratio [OR] 1.10; 99% confidence interval [CI] 0.43-2.84; p=0.791), infection (OR 0.77; 99% CI 0.45-1.34; p=0.220), acute kidney injury (OR 1.03; 99% CI 0.65-1.62; p=0.876) or cumulative chest tube output (adjusted mean difference 8 hrs post transfusion, 11 mL; 99% CI -104 to 125; p=0.804).

CONCLUSIONS

Although cryoprecipitate was typically given to sicker patients with more bleeding, its administration was not associated with worse outcomes. Large, multicentred studies are warranted to further elucidate cryoprecipitate's safety profile and patterns of use in cardiac surgery.

Preparation of Cryoprecipitate and Cryo-depleted Plasma for Proteomic Research Analysis

When frozen plasma is slowly thawed in cold conditions (1-6 °C), high-molecular-weight plasma proteins precipitate forming a concentrate known as cryoprecipitate. The concentrate is enriched with several important coagulation proteins, including fibrinogen, antihemophilic factor (factor VIII), von Willebrand factor, fibrin stabilizing factor (factor XIII), fibronectin, and small amounts of other plasma proteins. In current medical practice, clinical-grade preparations of cryoprecipitate are used mostly to correct fibrinogen deficiency caused by acute blood loss or due to functional abnormalities of the fibrinogen protein. In the past, cryoprecipitate was used to treat von Willebrand disease and hemophilia A (factor VIII deficiency), but the availability of more highly purified coagulation factor concentrates or recombinant protein preparations has superseded the use of cryoprecipitate for these coagulopathies. Cryo-depleted plasma (also called cryosupernatant) is the plasma supernatant remaining following removal of the cryoprecipitate from frozen-thawed plasma and contains all the remaining soluble plasma proteins. This protocol describes the research-scale preparation of cryoprecipitate and cryo-depleted plasma suitable for proteomic studies and is based on the procedures used to prepare clinical-grade cryoprecipitate.

Preparation and Storage of Cryoprecipitate Derived from Amotosalen and UVA-Treated Apheresis Plasma and Assessment of In Vitro Quality Parameters

Cryoprecipitate is a plasma-derived blood product, enriched for fibrinogen, factor VIII, factor XIII, and von Willebrand factor. Due to infectious risk, the use of cryoprecipitate in Central Europe diminished over the last decades. However, after the introduction of various pathogen-reduction technologies for plasma, cryoprecipitate production in blood centers is a feasible alternative to pharmaceutical fibrinogen concentrate with a high safety profile. In our study, we evaluated the feasibility of the production of twenty-four cryoprecipitate units from pools of two units of apheresis plasma pathogen reduced using amotosalen and ultraviolet light A (UVA) (INTERCEPT^® Blood System). The aim was to assess the compliance of the pathogen-reduced cryoprecipitate with the European Directorate for the Quality of Medicines (EDQM) guidelines and the stability of coagulation factors after frozen (≤−25 °C) storage and five-day liquid storage at ambient temperature post-thawing. All pathogen-reduced cryoprecipitate units fulfilled the European requirements for fibrinogen, factor VIII and von Willebrand factor content post-preparation. After five days of liquid storage, content of these factors exceeded the minimum values in the European requirements and the content of other factors was sufficient. Our method of production of cryoprecipitate using pathogen-reduced apheresis plasma in a jumbo bag is feasible and efficient.

Practice patterns of ABO-matching for cryoprecipitate and patient outcomes after ABO-compatible versus incompatible cryoprecipitate

BACKGROUND AND OBJECTIVES

This sub-study of the FIBRES trial sought to examine the patterns of ABO-compatible cryoprecipitate administration and to identify adverse consequences of ABO-incompatible cryoprecipitate.

MATERIALS AND METHODS

This was a post hoc analysis of data collected from the FIBRES randomized clinical trial comparing fibrinogen concentrate with cryoprecipitate in the treatment of bleeding related to hypofibrinogenemia after cardiac surgery. The primary outcome was the percentage of administered cryoprecipitate that was ABO-compatible. Secondary outcomes were adverse events at 28 days. A follow-up survey was distributed to the FIBRES participating sites to examine the rationale behind the identified cryoprecipitate ABO-matching practice patterns.

RESULTS

A total of 363 patients were included: 53 (15%) received ABO-incompatible cryoprecipitate and 310 (85%) received ABO-compatible cryoprecipitate. There was an increased incidence of post-operative anaemia in the ABO-incompatible group (15; 28.3%) in comparison to the ABO-compatible (44; 14.2%) group (p = 0.01) at 28 days, which was unrelated to haemolysis, without a significant difference in transfusion requirement. In the multivariable logistic regression models accounting for clustering by site, there was no observed statistically significant association between the administration of ABO-incompatible cryoprecipitate and any other adverse outcomes. Nine out of 11 sites did not have a policy requiring ABO-matched cryoprecipitate.

CONCLUSION

This sub-study demonstrated that most cryoprecipitate administered in practice is ABO-compatible, despite the absence of guidelines or blood bank policies to support this practice. A signal towards increased risk of post-operative anaemia may be explained by higher rates of urgent surgery (vs. elective) in the ABO-incompatible group. Future studies should prospectively examine the impact of ABO-compatible versus incompatible cryoprecipitate to conclusively establish if there is a meaningful clinical impact associated with the administration of ABO-incompatible cryoprecipitate.

Clinical Benefits of Early Concurrent Use of Cryoprecipitate and Plasma Compared With Plasma Only in Bleeding Trauma Patients

OBJECTIVES

The effectiveness of cryoprecipitate (Cryo) in trauma has not been well established; the benefits of Cryo might have been overestimated in previous studies since the difference in the total amount of administered clotting factors was not considered. We aimed to evaluate the benefits of the concurrent use of Cryo in combination with fresh frozen plasma (FFP) for bleeding trauma patients.

DESIGN

Retrospective cohort study.

SETTING

The American College of Surgeons Trauma Quality Improvement Program database between 2015 and 2019.

PATIENTS

Patients who received greater than or equal to 5 units of packed RBCs and at least 1 unit of FFP within the first 4 hours after arrival to a hospital were included and dichotomized according to whether Cryo was used within the first 4 hours of hospital arrival.

INTERVENTION

None.

MEASUREMENTS AND MAIN RESULTS

The outcomes of patients treated with Cryo and FFP were compared with those treated with FFP only using propensity score-matching analysis. The dose of administered clotting factors in each group was balanced. The primary outcome was inhospital mortality, and the secondary outcome was the occurrence rate of adverse events. A total of 24,002 patients (Cryo+FFP group: 6,018; FFP only group: 17,984) were eligible for analysis, of whom 4,852 propensity score-matched pairs were generated. Significantly lower inhospital mortality (1,959 patients [40.4%] in the Cryo+FFP group vs 2,142 patients [44.1%] in the FFP only group; odds ratio [OR], 0.86; 95% CI, 0.79-0.93) was observed in the Cryo+FFP group; no significant difference was observed in the occurrence rate of adverse events (1,857 [38.3%] vs 1,875 [38.6%]; OR, 1.02; 95% CI, 0.94-1.10). Several sensitivity analyses showed similar results.

CONCLUSIONS

Cryo use combined with FFP was significantly associated with reduced mortality in bleeding trauma patients. Future randomized controlled trials are warranted to confirm these results.

Weight-adjusted dosing of fibrinogen concentrate and cryoprecipitate in the treatment of hypofibrinogenaemic bleeding adult cardiac surgical patients: a post hoc analysis of the Fibrinogen Replenishment in cardiac surgery randomised controlled trial

Background

Hypofibrinogenaemia is associated with excessive bleeding after cardiac surgery. Our aim was to compare the efficacy and safety of weight-adjusted vs empiric dosing of fibrinogen replacement in cardiac surgery.

Methods

In the Fibrinogen Replenishment in Cardiac Surgery (FIBRES) RCT, patients (n=735) received fibrinogen concentrate (4 g) or cryoprecipitate (10 units). In this post-hoc analysis, patients were grouped into quartiles based on increasing weight-adjusted dosing. Generalised estimating equations were used to account for hospital site, age, sex, surgical complexity, urgency, and critical preoperative status. The primary outcome was the number of units of red blood cells transfused within 24 h of cardiopulmonary bypass. Secondary outcomes included allogeneic blood components within 24 h, tamponade or major bleeding, and thromboembolic complications, ischaemic complications, or both within 28 days of cardiopulmonary bypass.

Results

The median weight-adjusted doses were 52 mg kg-1 of fibrinogen concentrate (inter-quartile range [IQR], 45-61; n=372) and 1.30 units per 10 kg of cryoprecipitate (IQR, 1.11-1.54; n=363). When patients were divided into quartiles of lowest to highest weight-adjusted dosing, no differences were seen in the primary outcome of red blood cell units transfused within 24 h of cardiopulmonary bypass between the lowest and highest quartiles in either the fibrinogen group (adjusted relative risk [RR]=0.90; 95% confidence interval [CI], 0.71-1.13; P=0.36) or the cryoprecipitate group (adjusted RR=1.04; 95% CI, 0.76-1.43; P=0.80). Results were similar for all secondary outcomes.

Conclusion

Outcomes for the lowest and highest weight-adjusted doses of fibrinogen replacement were comparable. Weight-adjusted dosing does not appear to offer advantages over empiric dosing in this context.

Clinical trial registration

NCT03037424.

Cryoprecipitate use during massive transfusion: A propensity score analysis

INTRODUCTION

Cryoprecipitate is frequently administered as an adjunct to balanced transfusion in the setting of traumatic hemorrhage. However, civilian studies have not demonstrated a clear survival advantage, and prior observational studies noted selection bias when analyzing cryoprecipitate use. Additionally, due to the logistics involved in cryoprecipitate administration, it is inconsistently implemented alongside standardized massive transfusion protocols. This study aims to evaluate the effects of early cryoprecipitate administration on inpatient mortality in the setting of massive transfusion for exsanguinating trauma and to use propensity score analysis to minimize selection bias.

METHODS

The registry of an urban level 1 trauma center was queried for adult patients who received at least 6 units of packed red blood cells within 4 h of presentation. Univariate analysis, multiple logistic regression, and propensity score matching were performed.

RESULTS

562 patients were identified. Patients with lower median RTS (6.86 (IQR 4.09-7.84) vs 7.6 (IQR 5.97-7.84), P<0.01), decreased Glasgow coma scale (12 (IQR 4-15) vs 15 (IQR 10-15), P<0.01), and increased lactate (7.5 (IQR 4.3-10.2) vs 4.9 (IQR 3.1-7.2), P<0.01) were more commonly administered cryoprecipitate. Mortality was greater among those who received cryoprecipitate (40.2% vs 23.7%, p<0.01) on univariate analysis. Neither multiple logistic regression (OR 0.917; 95% confidence interval 0.462-1.822; p = 0.805) nor propensity score matching (average treatment effect on the treated 2.3%, p = 0.77) revealed that cryoprecipitate administration was associated with a difference in inpatient mortality.

CONCLUSIONS

Patients receiving cryoprecipitate within 4 h of presentation were more severely injured at presentation and had increased inpatient mortality. Multivariable logistic regression and propensity score analysis failed to show that early administration of cryoprecipitate was associated with survival benefit for exsanguinating trauma patients. The prospect of definitively assessing the utility of cryoprecipitate in exsanguinating hemorrhage warrants prospective investigation.

Engineered Molecular Therapeutics Targeting Fibrin and the Coagulation System: a Biophysical Perspective

The coagulation cascade represents a sophisticated and highly choreographed series of molecular events taking place in the blood with important clinical implications. One key player in coagulation is fibrinogen, a highly abundant soluble blood protein that is processed by thrombin proteases at wound sites, triggering self-assembly of an insoluble protein hydrogel known as a fibrin clot. By forming the key protein component of blood clots, fibrin acts as a structural biomaterial with biophysical properties well suited to its role inhibiting fluid flow and maintaining hemostasis. Based on its clinical importance, fibrin is being investigated as a potentially valuable molecular target in the development of coagulation therapies. In this topical review, we summarize our current understanding of the coagulation cascade from a molecular, structural and biophysical perspective. We highlight single-molecule studies on proteins involved in blood coagulation and report on the current state of the art in directed evolution and molecular engineering of fibrin-targeted proteins and polymers for modulating coagulation. This biophysical overview will help acclimatize newcomers to the field and catalyze interdisciplinary work in biomolecular engineering toward the development of new therapies targeting fibrin and the coagulation system.

Blood transfusion trends in the United States: national inpatient sample, 2015 to 2018

There is significant decline in RBC and plasma transfusions nationally among hospitalized patients in the United States through 2018.

Increased cryoprecipitate use suggests wider adoption of hypofibrinogenemia management and hemostasis testing for coagulopathic patients.

Blood transfusions are among the most common therapeutic procedures performed in hospitalized patients. This study evaluates contemporary national trends in red blood cell (RBC), plasma, platelet, and cryoprecipitate transfusions. National Inpatient Sample, the largest all-payer inpatient database representing 94% to 97% of the US population, was evaluated from the fourth quarter (Q4) of 2015 through 2018. Quarterly trends for the percentage of hospitalizations with a transfusion procedure were separately examined for each blood product using log binomial regression and reported as quarterly percent change (QPC). The percentage of hospitalizations with an RBC transfusion decreased from 4.22% (2015Q4) to 3.79% (2018Q4) (QPC = −0.72; 95% confidence interval [CI], −1.26 to −0.19; P_trend = .008). Although plasma transfusions also decreased, QPC = −1.33 (95% CI, −2.00 to −0.65; P_trend < .001), platelet transfusions remained stable QPC = −0.13 (95% CI, −0.99 to 0.73; P_trend = .766). In contrast, hospitalizations with cryoprecipitate utilization significantly increased QPC = 2.01 (95% CI, 0.57 to 3.44; P_trend = .006). Significant quarterly reductions in RBC transfusions were also seen among many, but not all, strata of sex, race/ethnicity, patient risk severity, and admission type (elective vs nonelective). Despite significant declines in RBC transfusions among older adults, there were no significant changes among pediatric age-group (<18 years) and those 18 to 49 years. The decline in RBC and plasma transfusions suggests steady incorporation of robust evidence base showing safety of restrictive transfusions. Increased cryoprecipitate use may be reflective of wider adoption of hypofibrinogenemia management and hemostasis testing for coagulopathic patients.

Cryoprecipitate transfusion in bleeding patients

OBJECTIVES

The management of acquired coagulopathy in multiple clinical settings frequently involves fibrinogen supplementation. Cryoprecipitate, a multidonor product, is widely used for the treatment of acquired hypofibrinogenemia following massive bleeding, but it has been associated with adverse events. We aimed to review the latest evidence on cryoprecipitate for treatment of bleeding.

METHODS

We conducted a narrative review of current literature on cryoprecipitate therapy, describing its history, formulations and preparation, and recommended dosing. We also reviewed guideline recommendations on the use of cryoprecipitate in bleeding situations and recent studies on its efficacy and safety.

RESULTS

Cryoprecipitate has a relatively high fibrinogen content; however, as it is produced by pooling fresh frozen donor plasma, the fibrinogen content per unit can vary considerably. Current guidelines suggest that cryoprecipitate use should be limited to treating hypofibrinogenemia in patients with clinical bleeding. Until recently, cryoprecipitate was deemed unsuitable for pathogen reduction, and potential safety concerns and lack of standardized fibrinogen content have led to some professional bodies recommending that cryoprecipitate is only indicated for the treatment of bleeding and hypofibrinogenemia in perioperative settings where fibrinogen concentrate is not available. While cryoprecipitate is effective in increasing plasma fibrinogen levels, data on its clinical efficacy are limited.

CONCLUSIONS

There is a lack of robust evidence to support the use of cryoprecipitate in bleeding patients, with few prospective, randomized clinical trials performed to date. Clinical trials in bleeding settings are needed to investigate the safety and efficacy of cryoprecipitate and to determine its optimal use and administration.

A Rare Case of Factor XIII Deficiency in the Setting of Cancer Immunotherapy

Factor XIII deficiency is a rare bleeding disorder, which may be congenital or acquired, and is most commonly diagnosed in early childhood. It has a prevalence that is as low as one in 5,000,000. Acquired factor XIII deficiency is considered to be a more rare form, with less than 100 cases reported in the literature. This disorder can be clinically characterized by recurrent and severe unexplained bleeding. This case describes a patient with no prior bleeding disorders, who suffered from recurrent bleeding episodes while being treated with cancer immunotherapy, specifically pembrolizumab, and was subsequently diagnosed with factor XIII deficiency. She required cryoprecipitate infusion due to the persistent bleeding and subsequently developed saddle pulmonary embolism. The patient was not a candidate for tissue plasminogen activator (tPA) due to her recurrent bleeding and required mechanical thrombectomy. Given the timeline of symptoms, the patient likely developed acquired factor XIII deficiency due to her cancer immunotherapy.

Effects of pathogen reduction technology and storage duration on the ability of cryoprecipitate to rescue induced coagulopathies in vitro

Background

Fibrinogen concentrates and cryoprecipitate are currently used for fibrinogen supplementation in bleeding patients with dysfibrinogenemia. Both products provide an abundant source of fibrinogen but take greater than 10 min to prepare for administration. Fibrinogen concentrates lack coagulation factors (i.e., factor VIII [FVIII], factor XIII [FXIII], von Willebrand factor [VWF]) important for robust hemostatic function. Cryoprecipitate products contain these factors but have short shelf lives (<6 h). Pathogen reduction (PR) of cryoprecipitate would provide a shelf‐stable immediately available adjunct containing factors important for rescuing hemostatic dysfunction.

Study Design and Methods

Hemostatic adjunct study products were psoralen‐treated PR‐cryoprecipitated fibrinogen complex (PR‐Cryo FC), cryoprecipitate (Cryo), and fibrinogen concentrates (FibCon). PR‐Cryo FC and Cryo were stored for 10 days at 20–24°C. Adjuncts were added to coagulopathies (dilutional, 3:7 whole blood [WB]:normal saline; or lytic, WB + 75 ng/ml tissue plasminogen activator), and hemostatic function was assessed by rotational thromboelastometry and thrombin generation.

Results

PR of cryoprecipitate did not reduce levels of FVIII, FXIII, or VWF. PR‐Cryo FC rescued dilutional coagulopathy similarly to Cryo, while generating significantly more thrombin than FibCon, which also rescued dilutional coagulopathy. Storage out to 10 days at 20–24°C did not diminish the hemostatic function of PR‐Cryo FC.

Discussion

PR‐Cryo FC provides similar and/or improved hemostatic rescue compared to FibCon in dilutional coagulopathies, and this rescue ability is stable over 10 days of storage. In hemorrhaging patients, where every minute delay is associated with a 5% increase in mortality, the immediate availability of PR‐Cryo FC has the potential to improve outcomes.

The role of cryoprecipitate in human and canine transfusion medicine

OBJECTIVE

To evaluate the current role of cryoprecipitate in human and canine transfusion medicine.

DATA SOURCES

Human and veterinary scientific reviews and original studies found using PubMed and CAB Abstract search engines were reviewed.

HUMAN DATA SYNTHESIS

In the human critical care setting, cryoprecipitate is predominantly used for fibrinogen replenishment in bleeding patients with acute traumatic coagulopathy. Other coagulopathic patient cohorts for whom cryoprecipitate is recommended include those undergoing cardiovascular or obstetric procedures or patients bleeding from advanced liver disease. Preferential selection of cryoprecipitate versus fibrinogen concentrate (when available) is currently being investigated. Also a matter of ongoing debate is whether to administer this product as part of a fixed-dose massive hemorrhage protocol or to incorporate it into a goal-directed transfusion algorithm applied to the individual bleeding patient.

VETERINARY DATA SYNTHESIS

Although there are sporadic reports of the use of cryoprecipitate in dogs with heritable coagulopathies, there are few to no data pertaining to its use in acquired hypofibrinogenemic states. Low fibrinogen in dogs (as in people) has been documented with acute traumatic coagulopathy, advanced liver disease, and disseminated intravascular coagulation. Bleeding secondary to these hypocoagulable states may be amenable to cryoprecipitate therapy. Indications for preferential selection of cryoprecipitate (versus fresh frozen plasma) remain to be determined.

CONCLUSIONS

In the United States, cryoprecipitate remains the standard of care for fibrinogen replenishment in the bleeding human trauma patient. Its preferential selection for this purpose is the subject of several ongoing human clinical trials. Timely incorporation of cryoprecipitate into the transfusion protocol of the individual bleeding patient with hypofibrinogenemia may conserve blood products, mitigate adverse transfusion-related events, and improve patient outcomes. Cryoprecipitate is readily available, effective, and safe for use in dogs. The role of this blood product in clinical canine patients with acquired coagulopathy remains unknown.

Global sources of cryoprecipitate demonstrate variability in coagulant factor levels and functional hemostasis

Cryoprecipitate (cryo) is a plasma-derived blood product utilized during trauma resuscitation, surgery, and other major bleeding. Although local quality control metrics exist, inherent donor variability, and processing may confer differences in hemostatic effect between sources. The purposes of this study were to quantify procoagulant content in three global sources of cryo and evaluate their functional hemostatic effect. In this Institutional Review Board exempt study, 24 units of group A cryo from three different sources, American Red Cross single donor and pooled donor, Australian Red Cross single donor, Southwestern United States single donor, and Southwest pooled donor, were evaluated. Procoagulant factors were quantified from each source using ELISA and automated clot-based assays. Functional hemostasis was evaluated using rotational Thromboelastometry (ROTEM). Microparticles isolated from cryo units were enumerated and evaluated for cellular origin by flow cytometry, as well as their capacity to support thrombin generation. Southwestern United States single donor units demonstrated highest levels of fibrinogen, fibronectin, factor VIII, and von Willebrand factor in the selected units. In the coagulopathy model, successive doses from all cryo units were significantly correlated to decreasing coagulation time (P = 0.0100), and increasing maximum clot firmness (P = 0.0002) and alpha angle (P = 0.0009). Southwest pooled donor demonstrated significantly shorter coagulation time at all three doses (P = 0.02) than other sources. Microparticles support prothrombinase activity and thrombin generation. In this study of global cryo sources, procoagulant activity and in-vitro clot formation varied by source. This could be explained by variance in production and storage protocols. Further study is warranted to assess functional variance in cryo to optimize and standardize the use of cryo products.

A novel modified thaw-siphon method for extracting cryoprecipitate: The Bokutoh-siphon method

BACKGROUND

Cryoprecipitate (CRYO) is neither produced nor supplied by the Japanese Red Cross Society. A novel CRYO extraction method established in-house by modifying a thaw-siphon technique was demonstrated in this study.

STUDY DESIGN AND METHODS

A pack of fresh frozen plasma was thawed and equally divided into two bags for CRYO extraction by different methods. CRYO was extracted from the blood plasma using a standard centrifugation method and our modified thaw-siphon method (Bokutoh-siphon method; B method). The two different CRYOs extracted were analyzed to compare the differences in the amount of fibrinogen recovered, clotting factors extracted, and clotting activity.

RESULTS

The amount of fibrinogen in the CRYO extracted using the B-siphon method was similar to that obtained using the standard method (recovery of fibrinogen: B-siphon method: 71.2% vs. standard method: 61.0%). The amount of clotting XIII factor extracted using the B-siphon method was significantly lower than those extracted using the standard method. On the other hand, clotting II, V factors, and C1q esterase inhibitor not concentrated in CRYO content from the B-siphon method were significantly higher than that from the standard method.

CONCLUSION

A new in-house CRYO preparation method was established by modifying a previously used thaw-siphon method. A coagulation factor-rich CRYO was extracted from plasma frozen at -40°C along with the first fraction of thawed plasma, without using a large-capacity refrigerated centrifuge for blood bags.

Hemostatic defects in massive transfusion: an update and treatment recommendations

INTRODUCTION

Acute hemorrhage is a global healthcare issue, and remains the leading preventable cause of death in trauma. Acute severe hemorrhage can be related to traumatic, peripartum, gastrointestinal, and procedural causes. Hemostatic defects occur early in patients requiring massive transfusion. Early recognition and treatment of hemorrhage and hemostatic defects are required to save lives and to achieve optimal patient outcomes.

AREAS COVERED

This review discusses current evidence and trials aimed at identifying the optimal treatment for hemostatic defects in hemorrhage and massive transfusion. Literature search included PubMed and Embase.

EXPERT OPINION

Patients with acute hemorrhage requiring massive transfusion commonly develop coagulopathy due to specific hemostatic defects, and accurate diagnosis and prompt correction are required for definitive hemorrhage control. Damage control resuscitation and massive transfusion protocols are optimal initial treatment strategies, followed by goal-directed individualized resuscitation using real-time coagulation monitoring. Distinct phenotypes exist in trauma-induced coagulopathy, including 'Bleeding' or 'Thrombotic' phenotypes, and hyperfibrinolysis vs. fibrinolysis shutdown. The trauma 'lethal triad' (hypothermia, coagulopathy, acidosis) has been updated to the 'lethal diamond' (including hypocalcemia). A number of controversies in optimal management exist, including whole blood vs. component therapy, use of factor concentrates vs. blood products, optimal use of tranexamic acid, and prehospital plasma and tranexamic acid administration.

Targeted cryoprecipitate transfusion in severe traumatic haemorrhage

BACKGROUND

Severe traumatic haemorrhage is the leading cause of death in young adults. Trauma Induced Coagulopathy is a complex and multifactorial phenomenon associated with severe traumatic haemorrhage. Fibrinogen is one of the first coagulation factors to become depleted in TIC and evidence suggests that severely injured trauma patients with hypofibrinogenaemia have poor outcomes. It is postulated that early fibrinogen replacement can improve clinical outcomes. This study investigated cryoprecipitate transfusion in hyopfibrinogeneamic trauma patients.

METHODS

This retrospective, single center, observational study investigated the use of cryoprecipitate in severely injured trauma patients admitted to an Australian Level I Trauma Centre. The primary outcome was time to administration of cryoprecipitate after identification of hypofibrinogenaemia using ROTEM (FIBTEM A5). Data collected included demographics, ISS, laboratory values of coagulation and blood product usage.

RESULTS

71 patients received cryoprecipitate with a median time of 61 minutes [IQR 37-93] from FIBTEM A5 result to initial cryoprecipitate administration. At 24 hours following admission to ED, Clauss Fibrinogen levels increased by 1.30g/L [IQR 0.45-1.85] and FIBTEM A5 assay increased by 8mm [IQR 3.0-11.3]. Changes in both variables were highly significant (p<0.001) and Clauss Fibrinogen versus FIBTEM A5 values showed moderate to strong correlation (R=0.75-0.80).

CONCLUSION

This study demonstrated that early administration of cryoprecipitate was both feasible and efficacious in fibrinogen replacement in severe traumatic haemorrhage. High-level evidence supporting cryoprecipitate or fibrinogen concentrate replacement with regards to efficacy and feasibility is required to guide future clinical practice. This study provided baseline data to inform the design of further clinical trials investigating fibrinogen replacement in traumatic haemorrhage.

The effect of pathogen inactivation on cryoprecipitate: a functional and quantitative evaluation

BACKGROUND

As a pooled donor blood product, cryoprecipitate (cryo) carries risks of pathogen transmission. Pathogen inactivation (PI) improves the safety of cryoprecipitate, but its effects on haemostatic properties remain unclear. This study investigated protein expression in samples of pathogen inactivated cryoprecipitate (PI-cryo) using non-targeted quantitative proteomics and in vitro haemostatic capacity of PI-cryo.

MATERIALS AND METHODS

Whole blood (WB)- and apheresis (APH)-derived plasma was subject to PI with INTERCEPT^® Blood System (Cerus Corporation, Concord, CA, USA) and cryo was prepared from treated plasma. Protein levels in PI-cryo and paired controls were quantified using liquid chromatography-tandem mass spectrometry. Functional haemostatic properties of PI-cryo were assessed using a microparticle (MP) prothrombinase assay, thrombin generation assay, and an in vitro coagulopathy model subjected to thromboelastometry.

RESULTS

Over 300 proteins were quantified across paired PI-cryo and controls. PI did not alter the expression of coagulation factors, but levels of platelet-derived proteins and platelet-derived MPs were markedly lower in the WB PI-cryo group. Compared to controls, WB (but not APH) cryo samples demonstrated significantly lower MP prothrombinase activity, prolonged clotting time, and lower clot firmness on thromboelastometry after PI. However, PI did not affect overall thrombin generation variables in either group.

DISCUSSION

Data from this study suggest that PI via INTERCEPT^® Blood System does not significantly impact the coagulation factor content or function of cryo but reduces the higher MP content in WB-derived cryo. PI-cryo products may confer benefits in reducing pathogen transmission without affecting haemostatic function, but further in vivo assessment is warranted.

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.

A cross-sectional study of prevalence, distribution, cause, and impact of blood product recalls in the United States

Defective blood products that are recalled because of safety or potency deviations can trigger adverse health events and constrict the nation's blood supply chain. However, the underlying characteristics and impact of blood product recalls are not fully understood. In this study, we identified 4700 recall events, 7 reasons for recall, and 144 346 units affected by recalls. Using geospatial mapping of the newly defined county-level recall event density, we discovered hot spots with high prevalence and likelihood of blood product recall events. Distribution patterns and distribution distances of recalled blood products vary significantly between product types. Blood plasma is the most recalled product (87 980 units), and leukocyte-reduced products (34 230 units) are recalled in larger numbers than non-leukocyte-reduced products (8076 units). Donor-related reasons (92 382 units) and sterility deviations (22 408 units) are the major cause of blood product recalls. Monetary loss resulting from blood product recalls is estimated to be $17.9 million, and economic sensitivity tests show that donor-related reasons and sterility deviations contribute most to the overall monetary burden. A total of 2.8 million days was required to resolve recall events, and probabilistic survival time analysis shows that sterility deviations and contamination took longer to resolve because of their systemic effect on blood collection and processing. Our studies demonstrate that better donor screening procedures, rigorous sterility requirements, improved containment methods, and mitigation of recall events in high-prevalence regions will enable a more robust blood supply chain.

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.

Haematological features, transfusion management and outcomes of massive obstetric haemorrhage: findings from the Australian and New Zealand Massive Transfusion Registry

Massive obstetric haemorrhage (MOH) is a leading cause of maternal morbidity and mortality world-wide. Using the Australian and New Zealand Massive Transfusion Registry, we performed a bi-national cohort study of MOH defined as bleeding at ≥20 weeks' gestation or postpartum requiring ≥5 red blood cells (RBC) units within 4 h. Between 2008 and 2015, we identified 249 cases of MOH cases from 19 sites. Predominant causes of MOH were uterine atony (22%), placenta praevia (20%) and obstetric trauma (19%). Intensive care unit admission and/or hysterectomy occurred in 44% and 29% of cases, respectively. There were three deaths. Hypofibrinogenaemia (<2 g/l) occurred in 52% of cases in the first 24 h after massive transfusion commenced; of these cases, 74% received cryoprecipitate. Median values of other haemostatic tests were within accepted limits. Plasma, platelets or cryoprecipitate were transfused in 88%, 66% and 57% of cases, respectively. By multivariate regression, transfusion of ≥6 RBC units before the first cryoprecipitate (odds ratio [OR] 3·5, 95% CI: 1·7-7·2), placenta praevia (OR 7·2, 95% CI: 2·0-26·4) and emergency caesarean section (OR 4·9, 95% CI: 2·0-11·7) were independently associated with increased risk of hysterectomy. These findings confirm MOH as a major cause of maternal morbidity and mortality and indicate areas for practice improvement.

Effect of Fibrinogen Concentrate vs Cryoprecipitate on Blood Component Transfusion After Cardiac Surgery: The FIBRES Randomized Clinical Trial

IMPORTANCE

Excessive bleeding is a common complication of cardiac surgery. An important cause of bleeding is acquired hypofibrinogenemia (fibrinogen level <1.5-2.0 g/L), for which guidelines recommend fibrinogen replacement with cryoprecipitate or fibrinogen concentrate. The 2 products have important differences, but comparative clinical data are lacking.

OBJECTIVE

To determine if fibrinogen concentrate is noninferior to cryoprecipitate for treatment of bleeding related to hypofibrinogenemia after cardiac surgery.

DESIGN, SETTING, AND PARTICIPANTS

Randomized clinical trial at 11 Canadian hospitals enrolling adult patients experiencing clinically significant bleeding and hypofibrinogenemia after cardiac surgery (from February 10, 2017, to November 1, 2018). Final 28-day follow-up visit was completed on November 28, 2018.

INTERVENTIONS

Fibrinogen concentrate (4 g; n = 415) or cryoprecipitate (10 units; n = 412) for each ordered dose within 24 hours after cardiopulmonary bypass.

MAIN OUTCOMES AND MEASURES

Primary outcome was blood components (red blood cells, platelets, plasma) administered during 24 hours post bypass. A 2-sample, 1-sided test for the ratio of the mean number of units was conducted to evaluate noninferiority (threshold for noninferiority ratio, <1.2).

RESULTS

Of 827 randomized patients, 735 (372 fibrinogen concentrate, 363 cryoprecipitate) were treated and included in the primary analysis (median age, 64 [interquartile range, 53-72] years; 30% women; 72% underwent complex operations; 95% moderate to severe bleeding; and pretreatment fibrinogen level, 1.6 [interquartile range, 1.3-1.9] g/L). The trial met the a priori stopping criterion for noninferiority at the interim analysis after 827 of planned 1200 patients were randomized. Mean 24-hour postbypass allogeneic transfusions were 16.3 (95% CI, 14.9 to 17.8) units in the fibrinogen concentrate group and 17.0 (95% CI, 15.6 to 18.6) units in the cryoprecipitate group (ratio, 0.96 [1-sided 97.5% CI, -∞ to 1.09; P < .001 for noninferiority] [2-sided 95% CI, 0.84 to 1.09; P = .50 for superiority]). Thromboembolic events occurred in 26 patients (7.0%) in the fibrinogen concentrate group and 35 patients (9.6%) in the cryoprecipitate group.

CONCLUSIONS AND RELEVANCE

In patients undergoing cardiac surgery who develop clinically significant bleeding and hypofibrinogenemia after cardiopulmonary bypass, fibrinogen concentrate is noninferior to cryoprecipitate with regard to number of blood components transfused in a 24-hour period post bypass. Use of fibrinogen concentrate may be considered for management of bleeding in patients with acquired hypofibrinogenemia in cardiac surgery.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03037424.

Review of current transfusion therapy and blood banking practices

Transfusion Medicine is a dynamically evolving field. Recent high-quality research has reshaped the paradigms guiding blood transfusion. As increasing evidence supports the benefit of limiting transfusion, guidelines have been developed and disseminated into clinical practice governing optimal transfusion of red cells, platelets, plasma and cryoprecipitate. Concepts ranging from transfusion thresholds to prophylactic use to maximal storage time are addressed in guidelines. Patient blood management programs have developed to implement principles of patient safety through limiting transfusion in clinical practice. Data from National Hemovigilance Surveys showing dramatic declines in blood utilization over the past decade demonstrate the practical uptake of current principles guiding patient safety. In parallel with decreasing use of traditional blood products, the development of new technologies for blood transfusion such as freeze drying and cold storage has accelerated. Approaches to policy decision making to augment blood safety have also changed. Drivers of these changes include a deeper understanding of emerging threats and adverse events based on hemovigilance, and an increasing healthcare system expectation to align blood safety decision making with approaches used in other healthcare disciplines.

In Vitro Assessment of von Willebrand Factor in Cryoprecipitate, Antihemophilic Factor/VWF Complex (Human), and Recombinant von Willebrand Factor

Patients with von Willebrand disease (VWD) often require treatment with supplemental von Willebrand factor (VWF) prior to procedures or to treat bleeding. Commercial VWF concentrates and more recently recombinant human VWF (rVWF) have replaced cryoprecipitate as the mainstay of therapy. In comparison with cryoprecipitate, the VWF content and multimer distribution under current manufacturing processes of these commercial products has not been reported. We measured the factor VIII (FVIII:C), VWF antigen (VWF:Ag), VWF collagen-binding activity (VWF:CB), VWF platelet-binding activity by GPIbM enzyme-linked immunosorbent assay (VWF:GPIbM), and percentage of high-molecular-weight (HMWM) VWF in 3 pools of group A and O cryoprecipitate, 3 vials of VWF concentrate (Humate-P), and 1 lot of rVWF (Vonvendi). We found that both group O and group A cryoprecipitate have significantly higher ratios of VWF:GPIbM activity and FVIII:C activity relative to VWF:Ag and have better preservation of HMWM than Humate-P. Although not compared statistically, rVWF appears to have more HMWM VWF and a higher ratio of VWF:GPIbM to VWF:Ag than Humate-P and cryoprecipitate. The estimated acquisition cost for our hospital for treating one major bleeding episode was more than 4-fold higher with Humate-P and 7- to 10-fold higher with rVWF than with cryoprecipitate.

Transfusion Triggers for Platelets and Other Blood Products

How to cite this article: Karanth S. Transfusion Triggers for Platelets and Other Blood Products. Indian J Crit Care Med 2019;23(Suppl 3):S189–S190.

Initial Results of Empirical Cryoprecipitate Transfusion in the Treatment of Isolated Severe Traumatic Brain Injury: Use of In-house-produced Cryoprecipitate

Acute coagulopathy is common after traumatic brain injury (TBI), particularly in severe cases of acute subdural hemorrhage (ASDH). Although acute coagulopathy is associated with poor outcomes, the optimal treatment strategy remains unknown. Here, we report the initial results of an empirical cryoprecipitate transfusion strategy that we developed as an early intervention for acute coagulopathy after TBI. We performed chart reviews of adult patients (aged ≥18 years) who received early cryoprecipitate transfusion after admission to our institution with a diagnosis of severe TBI (Glasgow Coma Scale ≤8) and ASDH from March 2013 to December 2016. We compared the outcomes of these patients with those who were treated before the implementation of the cryoprecipitate transfusion strategy (January 2011-February 2013). During the study period, 33 patients received early cryoprecipitate transfusion and no acute transfusion-related adverse event was reported. The rate of coagulopathy development within 24 h after admission was lower in these patients (23%) than in the controls (49%), but the difference was not significant (P = 0.062). The in-hospital mortality rate was 36% in patients receiving early cryoprecipitate transfusion and 52% in controls. After adjusting for confounding factors, the in-hospital mortality rate was significantly lower in the intervention period [adjusted odds ratio: 0.25, 95% confidence interval (CI): 0.08-0.78, P = 0.017]. In summary, we analyzed initial results of a cryoprecipitate transfusion strategy in patients with severe isolated TBI and ASDH. No acute transfusion-related adverse event was observed, and early transfusion of the in-house-produced cryoprecipitate may have reduced rates of coagulopathy development and in-hospital mortality.

Blood Products in the Management of Abnormal Placentation

A critical tool in the successful management of patients with abnormal placentation is an established massive transfusion protocol designed to rapidly deliver blood products in obstetrical and surgical hemorrhage. Spurred by trauma research and an understanding of consumptive coagulopathy, the past 2 decades have seen a shift in volume resuscitation from an empiric, crystalloid-based method to balanced, targeted transfusion therapy. The present article reviews patient blood management in abnormal placentation, beginning with optimizing the patient's status in the antenatal period to the laboratory assessment and transfusion strategy for blood products at the time of hemorrhage.

Effects of in-house cryoprecipitate on transfusion usage and mortality in patients with multiple trauma with severe traumatic brain injury: a retrospective cohort study

BACKGROUND

Hypofibrinogenaemia is a common complication of multiple trauma with severe traumatic brain injury (Abbreviated Injury Scale score of the head ≥4; body ≥3). In Japan, neither fibrinogen concentrate nor cryoprecipitate is permitted to treat acquired hypofibrinogenaemia with the purpose of rapidly restoring a haemostatic level of fibrinogen. The aim of this study was to investigate transfusion usage and mortality in patients with multiple trauma and severe traumatic brain injury who were given a cryoprecipitate prepared in-house, comparing those administered the product early or later.

MATERIAL AND METHODS

We prepared and produced cryoprecipitate from fresh-frozen plasma beginning in March 2013. We performed a retrospective cohort study of patients admitted to our single tertiary medical centre with severe multiple trauma with traumatic brain injury from March 2013 to June 2018, sorting them into those given the cryoprecipitate infusion within 90 minutes of admission (Early group) and those given it more than 90 minutes after admission (Late group). Clinical outcomes were compared between the two groups using chi-square or Fisher's exact tests and the Wilcoxon test as appropriate.

RESULTS

There were 26 and 16 patients in the Early and Late groups, respectively. The 24-hour mortality tended to be lower in the Early group than in the Late group (8 vs 13%, respectively). The patients were more severely anaemic and thrombocytopenic after haemostatic therapy in the Late group than in the Early group. Transfusion usage in the Early group was lower than that in the Late group (red blood cells: 7±1 units vs 17±3 units, p<0.05; fresh-frozen plasma: 9±1 units vs 16±3 units, p<0.05; platelet concentrate: 3±1 units vs 15±4 units, p<0.05, respectively).

DISCUSSION

Early administration of an in-house cryoprecipitate may reduce transfusion usage in patients with multiple trauma with severe traumatic brain injury.

Evaluation of reagents used to coat the hollow-fiber bioreactor membrane of the Quantum® Cell Expansion System for the culture of human mesenchymal stem cells

The addition of a coating reagent to promote cell adherence is necessary to prepare the membrane surface of the Quantum® Cell Expansion System hollow-fiber bioreactor for the culture of mesenchymal stem cells. In this study, the efficacy of 8 potential coating reagents has been compared in terms of the doubling times of their cell populations, cell morphology, characterization via flow cytometry, and capacity for trilineage differentiation. Human fibronectin (FN), pooled human cryoprecipitate (CPPT), and recombinant human vitronectin (VN) were successful as coating reagents, and each product has advantages in different cell culture contexts. Mesenchymal stem cells harvested from Quantum cultured with each of these 3 compounds as coating reagents all met International Society for Cellular Therapy standards for plastic adherence, surface marker expression, and successful trilineage differentiation. No significant differences were observed among the doubling times from Quantum harvests using FN, CPPT, or VN as coating reagents (P = 0.31). Coating with gelatin, human serum albumin, collagen I, poly‑l‑lysine, and poly‑d‑lysine resulted in significantly lower harvest yield; these agents are not recommended for use as coating reagents in the Quantum system.

Cryoprecipitate augments the global transduction of the adeno-associated virus serotype 9 after a systemic administration

Adeno-associated virus (AAV) vectors have been successfully used for transgene delivery in clinical trials. A systemic administration of AAV vectors has been proposed in order to achieve global transduction, which requires that the AAV vector is capable of crossing the blood vessels. It has been demonstrated that serum proteins are able to directly interact with AAV virions to enhance liver transduction. In this study, we investigate whether the serum proteins have the potential to increase the capacity of AAV to diffuse through the endothelial cells and deliver the transgene into the whole body. First, we found that the direct interaction of serum with AAV9 virions increased the epithelial cell permeability of AAV9 in vitro. Several serum proteins with a potential effect on AAV vascular permeability have been identified from mass spectrometry analysis, including fibrinogen, fibronectin, von Willebrand factor (vWF), platelet factor 4, alpha-1-acid glycoprotein, and plasminogen. The incubation of these serum proteins with AAV9 enhanced the global transduction in mice after a systemic administration. To apply these findings in clinical practice, we demonstrated that the clinical product cryoprecipitate (mainly containing fibrinogen and vWF) augmented AAV9 global transduction. The mechanism study revealed that cryoprecipitate slowed down the clearance of AAV9 vectors in the blood so that the AAV9 vectors had sufficient time to travel to the peripheral organs. In summary, the results from this study suggests that serum proteins interact with AAV virions and enhance the AAV9 vascular permeability for global transduction, and, more importantly, cryoprecipitate can be immediately applied for clinical patients who need the systemic administration of AAV vectors for global transduction.