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

Controversies and evidence gaps in the early management of severe traumatic brain injury: back to the ABCs

Traumatic brain injury (TBI) accounts for around 30% of all trauma-related deaths. Over the past 40 years, TBI has remained a major cause of mortality after trauma. The primary injury caused by the injurious mechanical force leads to irreversible damage to brain tissue. The potentially preventable secondary injury can be accentuated by addressing systemic insults. Early recognition and prompt intervention are integral to achieve better outcomes. Consequently, surgeons still need to be aware of the basic yet integral emergency management strategies for severe TBI (sTBI). In this narrative review, we outlined some of the controversies in the early care of sTBI that have not been settled by the publication of the Brain Trauma Foundation’s 4th edition guidelines in 2017. The topics covered included the following: mode of prehospital transport, maintaining airway patency while securing the cervical spine, achieving adequate ventilation, and optimizing circulatory physiology. We discuss fluid resuscitation and blood product transfusion as components of improving circulatory mechanics and oxygen delivery to injured brain tissue. An outline of evidence-based antiplatelet and anticoagulant reversal strategies is discussed in the review. In addition, the current evidence as well as the evidence gaps for using tranexamic acid in sTBI are briefly reviewed. A brief note on the controversial emergency surgical interventions for sTBI is included. Clinicians should be aware of the latest evidence for sTBI. Periods between different editions of guidelines can have an abundance of new literature that can influence patient care. The recent advances included in this review should be considered both for formulating future guidelines for the management of sTBI and for designing future clinical studies in domains with clinical equipoise.

Coagulopathy and Traumatic Brain Injury: Overview of New Diagnostic and Therapeutic Strategies

Coagulopathy is a common sequela of traumatic brain injury. Consumptive coagulopathy and secondary hyperfibrinolysis are associated with hypercoagulability. In addition, fibrinolytic pathways are hyperactivated as a result of vascular endothelial cell damage in the injured brain. Coagulation and fibrinolytic parameters change dynamically to reflect these pathologies. Fibrinogen is consumed and degraded after injury, with fibrinogen concentrations at their lowest 3-6 h after injury. Hypercoagulability causes increased fibrinolytic activity, and plasma levels of D-dimer increase immediately after traumatic brain injury, reaching a maximum at 3 h. Owing to disseminated intravascular coagulation in the presence of fibrinolysis, the bleeding tendency is highest within the first 3 h after injury, and often a condition called “talk and deteriorate” occurs. In neurointensive care, it is necessary to measure coagulation and fibrinolytic parameters such as fibrinogen and D-dimer routinely to predict and prevent the development of coagulopathy and its negative outcomes. Currently, the only evidence-based treatment for traumatic brain injury with coagulopathy is tranexamic acid in the subset of patients with mild-to-moderate traumatic brain injury. Coagulation and fibrinolytic parameters should be closely monitored, and treatment should be considered on a patient-by-patient basis.

Fibrinolysis in Traumatic Brain Injury: Diagnosis, Management, and Clinical Considerations

Posttraumatic coagulopathy involves disruption of both the coagulation and fibrinolytic pathways secondary to tissue damage, hypotension, and inflammatory upregulation. This phenomenon contributes to delayed complications after traumatic brain injury (TBI), including intracranial hemorrhage progression and systemic disseminated intravascular coagulopathy. Development of an early hyperfibrinolytic state may result in uncontrolled bleeding and is associated with increased mortality in patients with TBI. Although fibrinolytic assays are not routinely performed in the assessment of posttraumatic coagulopathy, circulating biomarkers such as D-dimer and fibrin degradation products have demonstrated potential utility in outcome prediction. Unfortunately, the relatively delayed nature of these tests limits their clinical utility. In contrast, viscoelastic tests are able to provide a rapid global assessment of coagulopathy, although their ability to reliably identify disruptions in the fibrinolytic cascade remains unclear. Limited evidence supports the use of hypertonic saline, cryoprecipitate, and plasma to correct fibrinolytic disruption; however, some studies suggest more harm than benefit. Recently, early use of tranexamic acid in patients with TBI and confirmed hyperfibrinolysis has been proposed as a strategy to further improve clinical outcomes. Moving forward, further delineation of TBI phenotypes and the clinical implications of fibrinolysis based on phenotypic variation is needed. In this review, we summarize the clinical aspects of fibrinolysis in TBI, including diagnosis, treatment, and clinical correlates, with identification of targeted areas for future research efforts.

Thromboelastography is a Marker for Clinically Significant Progressive Hemorrhagic Injury in Severe Traumatic Brain Injury

BACKGROUND

Coagulopathy in traumatic brain injury (TBI) is associated with increased risk of poor outcomes, but accurate prediction of clinically significant progressive hemorrhagic injury (PHI) in patients with severe TBI remains a challenge. Thromboelastography (TEG) is a real-time test of whole blood coagulation that provides dynamic information about global hemostasis. This study aimed to identify differences in TEG values between patients with severe TBI who did or did not experience clinically significant PHI.

METHODS

This was a single-center retrospective cohort study of adult patients with severe TBI. Patients were eligible for inclusion if initial Glasgow coma scale (GCS) was ≤ 8 and baseline head computed tomography (CT) imaging and TEG were available. Exclusion criteria included receipt of hemostatic agents prior to TEG. PHI was defined as bleeding expansion on CT within 24 h associated with 2-point drop in GCS, neurosurgical intervention, or mortality within 24 h. The primary endpoint was TEG value differences between patients with and without PHI. Secondary endpoints included differences in conventional coagulation tests (CCTs) between groups.

RESULTS

Of the 526 patients evaluated, 141 met inclusion criteria. The most common reason for exclusion was lack of baseline TEG and receipt of reversal product prior to TEG. Sixty-four patients experienced PHI in the first 24 h after presentation. K time (2.03 min vs. 1.33 min, P = 0.035) and alpha angle (65° vs. 69°, P = 0.015) were found to be significantly different in patients experiencing PHI. R time (5.25 min vs. 4.71 min), maximum amplitude (61 mm vs. 63 mm), and clot lysis at 30 min after maximum clot strength (3.5% vs. 1.7%) were not significantly different between groups. Of the CCTs, only activated partial thromboplastin time (30.3 s vs. 27.6 s, P = 0.014) was found to be different in patients with PHI.

CONCLUSIONS

Prolonged K time and narrower alpha angle were found to be associated with developing clinically significant PHI in patients with severe TBI. Despite differences detected in alpha angle, median values in both groups were within normal reference ranges. These abnormalities may reflect pathologic hypoactivity of fibrinogen, and further study is warranted to evaluate TEG-guided cryoprecipitate administration in this patient population.

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.