Cryoprecipitate use during massive transfusion: A propensity score analysis

Effect of early administration of fibrinogen replacement therapy in traumatic haemorrhage: a systematic review and meta-analysis of randomised controlled trials with narrative synthesis of observational studies

BACKGROUND

In severely injured trauma patients, hypofibrinoginaemia is associated with increased mortality. There is no evidence-based consensus for what constitutes optimal fibrinogen therapy, treatment dose or timing of administration. The aim of this systematic review was to evaluate the effects of early fibrinogen replacement, either cryoprecipitate or fibrinogen concentrate (FgC) on mortality, transfusion requirements and deep venous thrombosis (DVT).

METHODS

A systematic search of studies was performed on MEDLINE, EMBASE and clinicaltrials.gov databases using standardised search criteria. All clinical studies which examined the use of either cryoprecipitate or FgC in patients with traumatic haemorrhage within 4 h of admission to hospital were included. Primary outcome was mortality (28-day, 30-day or in-hospital). Secondary outcomes were DVT incidence and blood component transfusions. A narrative synthesis was performed for all observational studies. Meta-analysis was completed for all included RCTs for mortality with pre-defined sub-group analysis of FgC and cryoprecipitate use. Grading of Recommendations Assessment, Development, and Evaluation was used to assess the quality of evidence.

RESULTS

Overall, 1906 studies were screened with 12 studies included and five RCTs (all suitable for meta-analysis) totalling 1758 participants. Three RCTs reported FgC therapy, and two used cryoprecipitate. Four out of five RCTs examined empiric fibrinogen replacement for suspected traumatic haemorrhage. There was no difference in the primary outcome of mortality: early fibrinogen replacement (24%) vs control (25%), OR 1.03 (95% CI; 0.68-1.56). Subgroup analysis found no difference in outcome between the FgC and control: 18.1% vs 10.9% respectively, OR 1.99 (95% CI; 0.80-4.94). Similarly for cryoprecipitate, there was no difference in mortality between groups: cryoprecipitate (24.9%) vs control (26.1%), OR 0.71 (95% CI, 0.25-2.01). Reporting of transfusion data precluded meta-analysis. There was no difference in DVT incidence: fibrinogen replacement (3%) vs control (4%), OR 0.73 (0.43, 1.25). Overall, the quality of evidence was graded as low due to indirectness and imprecision.

CONCLUSIONS

There is no association between early fibrinogen replacement and mortality, DVT or transfusion requirements. We found no superiority between FgC or cryoprecipitate. This systematic review highlights the urgent need for further RCTs to assess the efficacy of early fibrinogen replacement, preferred strategy (goal-directed vs empiric) as well as optimal therapeutic product for both patient outcome and cost effectiveness.

O blood type is not associated with worse coagulopathy or outcome in exsanguinating trauma

BACKGROUND

Despite improving understanding of trauma-induced coagulopathy (TIC), mortality and morbidity due to exsanguinating trauma remain high. Increased complications due to hemorrhage have been reported in blood group O, possibly due to reduced levels of von Willebrand factor (vWF).

METHODS

An urban level 1 adult trauma center registry was retrospectively queried. Patients receiving ≥6 units of pRBC within 4 ​h of presentation were included. Patient demographics, admission labs and outcomes were obtained. Univariate and multiple logistic regression analyses were performed.

RESULTS

562 patients were identified. There were no significant differences in demographics, admission labs, or outcome between different ABO groups. After adjustment, Type A patients were more likely to be hypocoagulable compared to Type O patients (p ​= ​0.014). No mortality differences were seen between ABO types in multiple regression analysis.

CONCLUSIONS

No outcome or mortality differences were seen between ABO types, therefore factors other than vWF expression should be considered to explain coagulopathy in trauma patients.

Implementation and early outcomes with Pathogen Reduced Cryoprecipitated Fibrinogen Complex

OBJECTIVES

Cryoprecipitated antihemophilic factor (cryo) has been used for fibrinogen replacement in actively bleeding patients, dysfibrinogenemia, and hypofibrinogenemia. Cryo has a shelf life of 4 to 6 hours after thawing and a long turnaround time in issuing the product, posing a major limitation of its use. Recently, the US Food and Drug Administration approved Pathogen Reduced Cryoprecipitated Fibrinogen Complex (INTERCEPT Fibrinogen Complex [IFC]) for the treatment of bleeding associated with fibrinogen deficiency, which can be stored at room temperature and has a shelf life of 5 days after thawing.

METHODS

We identified locations and specific end users with high cryoprecipitate utilization and waste. We partnered with our blood supplier to use IFC in these locations. We analyzed waste and turnaround time before and after implementation.

RESULTS

Operative locations had a waste rate that exceeded nonoperative locations (16.7% vs 3%) and were targeted for IFC implementation. IFC was added to our inventory to replace all cryo orders from adult operating rooms, and waste decreased to 2.2% in these locations. Overall waste of cryoprecipitated products across all locations was reduced from 8.8% to 2.4%. The turnaround time for cryoprecipitated products was reduced by 58% from 30.4 minutes to 14.6 minutes.

CONCLUSIONS

There has been a substantial decrease in waste with improved turnaround time after IFC implementation. This has improved blood bank logistics, improved efficiency of patient care, and reduced costly waste.

Does an early, balanced resuscitation strategy reduce the incidence of hypofibrinogenemia in hemorrhagic shock?

Objectives

Some centers have recommended including concentrated fibrinogen replacement in massive transfusion protocols (MTPs). Given our center's policy of aggressive early balanced resuscitation (1:1:1), beginning prehospital, we hypothesized that our rates of hypofibrinogenemia may be lower than those previously reported.

Methods

In this retrospective cohort study, patients presenting to our trauma center November 2017 to April 2021 were reviewed. Patients were defined as hypofibrinogenemic (HYPOFIB) if admission fibrinogen <150 or rapid thrombelastography angle <60. Univariate and multivariable analyses assessed risk factors for HYPOFIB. Inverse probability of treatment weighting analyses assessed the relationship between cryoprecipitate administration and outcomes.

Results

Of 29 782 patients, 6618 level 1 activations, and 1948 patients receiving emergency release blood, <1%, 2%, and 7% were HYPOFIB. HYPOFIB patients were younger, had higher head Abbreviated Injury Scale value, and had worse coagulopathy and shock. HYPOFIB had lower survival (48% vs 82%, p<0.001), shorter time to death (median 28 (7, 50) vs 36 (14, 140) hours, p=0.012), and were more likely to die from head injury (72% vs 51%, p<0.001). Risk factors for HYPOFIB included increased age (OR (95% CI) 0.98 (0.96 to 0.99), p=0.03), head injury severity (OR 1.24 (1.06 to 1.46), p=0.009), lower arrival pH (OR 0.01 (0.001 to 0.20), p=0.002), and elevated prehospital red blood cell to platelet ratio (OR 1.20 (1.02 to 1.41), p=0.03). Among HYPOFIB patients, there was no difference in survival for those that received early cryoprecipitate (within 2 hours; 40 vs 47%; p=0.630). On inverse probability of treatment weighted analysis, early cryoprecipitate did not benefit the full cohort (OR 0.52 (0.43 to 0.65), p<0.001), nor the HYPOFIB subgroup (0.28 (0.20 to 0.39), p<0.001).

Conclusions

Low rates of hypofibrinogenemia were found in our center which treats hemorrhage with early, balanced resuscitation. Previously reported higher rates may be partially due to unbalanced resuscitation and/or delay in resuscitation initiation. Routine empiric inclusion of concentrated fibrinogen replacement in MTPs is not supported by the currently available data.

Level of evidence

Level III.

Optimal dose of cryoprecipitate in massive transfusion following trauma

BACKGROUND

While cryoprecipitate (Cryo) is commonly included in massive transfusion protocols for hemorrhagic shock, the optimal dose of Cryo transfusion remains unknown. We evaluated the optimal red blood cell (RBC) to RBC to Cryo ratio during resuscitation in massively transfused trauma patients.

METHODS

Adult patients in the American College of Surgeon Trauma Quality Improvement Program (2013-2019) receiving massive transfusion (≥4 U of RBCs, ≥1 U of fresh frozen plasma, and ≥1 U of platelets within 4 hours) were included. A unit of Cryo was defined as a pooled unit of 100 mL. The RBC:Cryo ratio was calculated for blood products transfused within 4 hours of presentation. The association between RBC:Cryo and 24-hour mortality was analyzed with multivariable logistic regression adjusting for the volume of RBC, plasma and platelet transfusions, global and regional injury severity, and other relevant variables.

RESULTS

The study cohort included 12,916 patients. Among those who received Cryo (n = 5,511 [42.7%]), the median RBC and Cryo transfusion volume within 4 hours was 11 U (interquartile range, 7-19 U) and 2 U (interquartile range, 1-3 U), respectively. Compared with no Cryo administration, only RBC:Cryo ratios ≤8:1 were associated with a significant survival benefit, while lower doses of Cryo (RBC:Cryo >8:1) were not associated with decreased 24-hour mortality. Compared with the maximum dose of Cryo administration (RBC:Cryo, 1:1-2:1), there was no difference in 24-hour mortality up to RBC:Cryo of 7:1 to 8:1, whereas lower doses of Cryo (RBC:Cryo, >8:1) were associated with significantly increased 24-hour mortality.

CONCLUSION

One pooled unit of Cryo (100 mL) per 7 to 8 U of RBCs could be the optimal dose of Cryo in trauma resuscitation that provides a significant survival benefit while avoiding unnecessary blood product transfusions.

LEVEL OF EVIDENCE

Prognostic and Epidemiologic; Level IV.