First-Line Administration of Fibrinogen Concentrate in the Bleeding Trauma Patient: Searching for Effective Dosages and Optimal Post-Treatment Levels Limiting Massive Transfusion-Further Results of the RETIC Study
Journal of clinical medicine. 2021;10(17)
Fibrinogen supplementation is recommended for treatment of severe trauma hemorrhage. However, required dosages and aimed for post-treatment fibrinogen levels remain a matter of discussion. Within the published RETIC study, adult patients suffering trauma-induced coagulopathy were randomly assigned to receive fibrinogen concentrate (FC) as first-line (n = 50) or crossover rescue (n = 20) therapy. Depending on bodyweight, a single dose of 3, 4, 5, or 6 g FC was administered and repeated if necessary (FibA10 < 9 mm). The dose-dependent response (changes in plasma fibrinogen and FibA10) was analyzed. Receiver operating characteristics (ROC) analysis regarding the need for massive transfusion and correlation analyses regarding fibrinogen concentrations and polymerization were performed. Median FC single doses amounted to 62.5 (57 to 66.66) mg.kg(-)(1). One FC single-dose sufficiently corrected fibrinogen and FibA10 (median fibrinogen 213 mg.dL(-1), median FibA10 11 mm) only in patients with baseline fibrinogen above 100 mg.dL(-1) and FibA10 above 5 mm, repeated dosing was required in patients with lower baseline fibrinogen/FibA10. Fibrinogen increased by 83 or 107 mg.dL(-1) and FibA10 by 4 or 4.5 mm after single or double dose of FC, respectively. ROC curve analysis revealed post-treatment fibrinogen levels under 204.5 mg.dL(-)(1) to predict the need for massive transfusion (AUC 0.652; specificity: 0.667; sensitivity: 0.688). Baseline fibrinogen/FibA10 levels should be considered for FC dosing as only sufficiently corrected post-treatment levels limit transfusion requirements.
Dynamics of Platelet Counts in Major Trauma: The Impact of Haemostatic Resuscitation and Effects of Platelet Transfusion-A Sub-Study of the Randomized Controlled RETIC Trial
Patients with major trauma enrolled in the RETIC study (n= 70).
Fibrinogen concentrate (FC) as first line medication (n= 50).
FC as crossover rescue medication (n= 20).
The dose-dependent response (changes in plasma fibrinogen and FibA10) was analysed. Median FC single doses amounted to 62.5 (57 to 66.66) mg.kg(-)(1). One FC single-dose sufficiently corrected fibrinogen and FibA10 (median fibrinogen 213 mg.dL(-1), median FibA10 11 mm) only in patients with baseline fibrinogen above 100 mg.dL(-1) and FibA10 above 5 mm, repeated dosing was required in patients with lower baseline fibrinogen/FibA10. Fibrinogen increased by 83 or 107 mg.dL(-1) and FibA10 by 4 or 4.5 mm after single or double dose of FC, respectively. Receiver operating characteristics curve analysis revealed post-treatment fibrinogen levels under 204.5 mg.dL(-)(1) to predict the need for massive transfusion (AUC 0.652; specificity: 0.667; sensitivity: 0.688).
J Clin Med. 2020;9(8)
Although platelets play a central role in haemostasis, the dynamics of platelet counts during haemostatic resuscitation, the response to platelet transfusion, and effects on clinical outcome are poorly described for trauma patients. As a sub-study of the already published randomized controlled RETIC Study "Reversal of Trauma-induced Coagulopathy using First-line Coagulation Factor Concentrates or Fresh-Frozen Plasma" trial, we here analysed whether the type of first-line haemostatic resuscitation influences the frequency of platelet transfusion and determined the effects of platelet transfusion in coagulopathic patients with major trauma. Patients randomly received first-line plasma (FFP) or coagulation factor concentrates (CFC), mainly fibrinogen concentrate. In both groups, platelets were transfused to maintain platelet counts between 50 and 100 × 10(9) /L. Transfusion rates were significantly higher in the FFP (n = 44) vs. CFC (n = 50) group (FFP 47.7% vs. CFC 26%); p = 0.0335. Logistic regression analysis adjusted for the stratification variables injury severity score (ISS) and brain injury confirmed that first-line FFP therapy increases the odds for platelet transfusion (odds ratio (OR) 5.79 (1.89 to 20.62), p = 0.0036) and this effect was larger than a 16-point increase in ISS (OR 4.33 (2.17 to 9.74), p =0.0001). In conclusion, early fibrinogen supplementation exerted a platelet-saving effect while platelet transfusions did not substantially improve platelet count and might contribute to poor clinical outcome.
Reversal of trauma-induced coagulopathy using first-line coagulation factor concentrates or fresh frozen plasma (RETIC): a single-centre, parallel-group, open-label, randomised trial
Trauma patients with trauma-induced coagulopathy (TIC) enrolled in the RETIC trial (n= 94).
First-line plasma (FFP), (n= 44).
Coagulation factor concentrates (CFC), (n= 50).
Transfusion rates were significantly higher for FFP 47.7% than CFC 26%. Logistic regression analysis adjusted for the stratification variables injury severity score and brain injury confirmed that first-line FFP therapy increases the odds for platelet transfusion.
The Lancet. Haematology. 2017;4((6):):e258-e271.. e258
BACKGROUND Effective treatment of trauma-induced coagulopathy is important; however, the optimal therapy is still not known. We aimed to compare the efficacy of first-line therapy using fresh frozen plasma (FFP) or coagulation factor concentrates (CFC) for the reversal of trauma-induced coagulopathy, the arising transfusion requirements, and consequently the development of multiple organ failure. METHODS This single-centre, parallel-group, open-label, randomised trial was done at the Level 1 Trauma Center in Innsbruck Medical University Hospital (Innsbruck, Austria). Patients with trauma aged 18-80 years, with an Injury Severity Score (ISS) greater than 15, bleeding signs, and plasmatic coagulopathy identified by abnormal fibrin polymerisation or prolonged coagulation time using rotational thromboelastometry (ROTEM) were eligible. Patients with injuries that were judged incompatible with survival, cardiopulmonary resuscitation on the scene, isolated brain injury, burn injury, avalanche injury, or prehospital coagulation therapy other than tranexamic acid were excluded. We used a computer-generated randomisation list, stratification for brain injury and ISS, and closed opaque envelopes to randomly allocate patients to treatment with FFP (15 mL/kg of bodyweight) or CFC (primarily fibrinogen concentrate [50 mg/kg of bodyweight]). Bleeding management began immediately after randomisation and continued until 24 h after admission to the intensive care unit. The primary clinical endpoint was multiple organ failure in the modified intention-to-treat population (excluding patients who discontinued treatment). Reversal of coagulopathy and need for massive transfusions were important secondary efficacy endpoints that were the reason for deciding the continuation or termination of the trial. This trial is registered with ClinicalTrials.gov, number NCT01545635. FINDINGS Between March 3, 2012, and Feb 20, 2016, 100 out of 292 screened patients were included and randomly allocated to FFP (n=48) and CFC (n=52). Six patients (four in the FFP group and two in the CFC group) discontinued treatment because of overlooked exclusion criteria or a major protocol deviation with loss of follow-up. 44 patients in the FFP group and 50 patients in the CFC group were included in the final interim analysis. The study was terminated early for futility and safety reasons because of the high proportion of patients in the FFP group who required rescue therapy compared with those in the CFC group (23 [52%] in the FFP group vs two [4%] in the CFC group; odds ratio [OR] 25.34 [95% CI 5.47-240.03], p<0.0001) and increased needed for massive transfusion (13 [30%] in the FFP group vs six [12%] in the CFC group; OR 3.04 [0.95-10.87], p=0.042) in the FFP group. Multiple organ failure occurred in 29 (66%) patients in the FFP group and in 25 (50%) patients in the CFC group (OR 1.92 [95% CI 0.78-4.86], p=0.15). INTERPRETATION Our results underline the importance of early and effective fibrinogen supplementation for severe clotting failure in multiple trauma. The available sample size in our study appears sufficient to make some conclusions that first-line CFC is superior to FFP. FUNDING None.
What is known?
The management of major trauma haemorrhage has changed significantly over the last two decades, and the use of haemostatic resuscitation (the transfusion of red cells and FFP early and in high ratio to mitigate/treat clotting abnormalities that arise from severe trauma haemorrhage) is now standard practice. There are attendant risks from the transfusion of blood components (TRALI, TACO, increased rates of multiple organ failure (MOF) in trauma) and the potential to use clotting factor concentrates (CFCs) such as prothrombin complex concentrate, factor XIII and fibrinogen in place of FFP may confer advantages.
What did this paper set out to examine?
The RETIC study was a single centre, open-label, RCT evaluating the effects of FFP vs. coagulation factor concentrates (CFCs) as treatment for major bleeding after injury in adult trauma patients (age 18 80). The primary endpoint was the development of MOF during ICU stay, as defined by the SOFA score. Secondary endpoints were numerous and included transfusion use, changes to clotting parameters, thromboembolic complications and mortality. The study was designed to detect a difference in MOF between groups notably the publication did not specify the difference expected and 292 patients were required for 80% power.
What did they show?
The study recruited 100 patients (48 FFP and 52 CFC) between March 2012 Feb 2016. Six patients were later excluded. 44FFP and 50 CFC patients were analysed. The baseline characteristics in each arm were balanced. The study was terminated early for safety 52% patients in FFP arm required rescue therapy (double dose therapy followed by switching to the other treatment to stop the bleeding) compared to 4% CFC group (OR: 25.34 [95% CI 5.47 240.03], p < 0.0001). Additionally more FFP patients received massive transfusion; OR 3.04 [0.95 10.87], p = 0.042.
Primary endpoint results were provided using a modified ITT population (patients randomised but did not complete therapy were removed). The study showed no significant difference in MOF between arms: 66% FFP arm vs. 50% CFC arm; OR 1.92 [95%CI 0.78 4.86], p = 0.15. Post-hoc logistic regression analysis showed a significant difference in MOF development in the FFP arm for patients who had higher injury severity and worse brain injury; OR 3.13 [1.19-8.88], p = 0.025. The CFC patients were more likely to have coagulopathy reversed OR 25.34 [5.47-240.03], p <0.0001. (Defined by: FIBTEM A10 >8mm, EXTEM CT < 78 secs and no clinical bleeding). Seven patients died 5 CFC and 2 FFP, most due to severe brain injury and no patient died from exsanguination.
What are the implications for practice and for future work?
Overall, given these limitations, there will be debate about the implications of this trial for practice. The findings regarding reversal of coagulopathy are intriging there is a clear agreement between reversal of coagulopathy i.e. a FIBTEM A10 >8mm, and an EXTEM CT < 78 secs and reduced bleeding. This is the first time, in an RCT setting, that improved ROTEM parameters have been linked to clinical reduction of bleeding and these findings are important. One particular area for further research might be to validate whether the ROTEM parameters are effective thresholds for bleeding treatment and importantly linking the thresholds with hard clinical outcomes such as mortality or significant reduction in transfusion therapy.