Tranexamic Acid Inhibits Hematoma Expansion in Intracerebral Hemorrhage and Traumatic Brain Injury. Does Blood Pressure Play a Potential Role? A Meta-Analysis from Randmized Controlled Trials

Association of fibrinolysis phenotype with patient outcomes following traumatic brain injury

BACKGROUND

Impaired coagulation is associated with elevated risk of mortality in trauma patients. Prior studies have demonstrated increased mortality in patients with hyperfibrinolysis (HF) and fibrinolysis shutdown (SD). In addition, prior studies have demonstrated no effect of tranexamic acid (TXA) on fibrinolysis phenotypes. We examined the association of admission fibrinolysis phenotype with traumatic brain injury (TBI) patient outcomes.

METHODS

Data were extracted from a placebo-controlled multicenter clinical trial. Patients ≥15 years with TBI (Glasgow Coma Scale score, 3-12) and systolic blood pressure ≥90 mm Hg were randomized in the out-of-hospital setting to receive placebo bolus/placebo infusion (Placebo), 1 gram (g) TXA bolus/1 g TXA infusion (bolus maintenance [BM]); or 2 g TXA bolus/placebo infusion (bolus only [BO]). Fibrinolysis phenotypes on admission were determined by clot lysis at 30 minutes (LY30): SD, ≤0.8%; physiologic, 0.9% to 2.9%; HF, ≥3%. Logistic regression was used to control for age, sex, penetrating injury, Injury Severity Score, maximum head AIS, and TXA treatment group.

RESULTS

Seven hundred forty-seven patients met inclusion criteria. Fibrinolysis shutdown was the most common phenotype in all treatment groups and was associated with increased age, Injury Severity Score, and presence of intracranial hemorrhage (ICH). Inpatient mortality was 15.2% for SD and HF, and 10.6% for physiologic ( p = 0.49). No differences in mortality, disability rating scale at 6 months, acute kidney injury, acute respiratory distress syndrome, or multi-organ failure were noted between fibrinolysis phenotypes.

CONCLUSION

SD is the most common phenotype expressed in moderate to severe TBI. In TBI, there is no association between fibrinolysis phenotype and mortality or other major complications.

LEVEL OF EVIDENCE

Prognostic and Epidemiological; Level IV.

Appraising the use of tranexamic acid in traumatic and non‐traumatic intracranial hemorrhage: A narrative review

Recently there has been increasing interest and debate on the use of tranexamic acid (TXA), an antifibrinolytic drug, in both traumatic and non‐traumatic intracranial hemorrhage. In this review we aim to discuss recent investigations looking at TXA in traumatic brain injury (TBI) and different categories of spontaneous intracranial hemorrhage. We also discuss differences between setting (hospital vs pre‐hospital), dosing and timing strategies, and other logistical challenges surrounding optimal use of TXA for isolated intracranial hemorrhage. Last, we hope to provide guidance for clinicians when considering the use of TXA in a patient with traumatic or non‐traumatic intracranial hemorrhage based on appraisal of the available literature as well as some potential ideas for future research in this area.

Effectiveness and Safety of Tranexamic Acid Use in Acute Traumatic Injury in the Prehospital and In-hospital Settings: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background and Objectives

This systematic review and meta-analysis of randomized controlled trials (RCTs) aims to assess efficacy and safety of tranexamic acid (TXA) use in acute traumatic injuries.

Methods

PubMed and Cochrane libraries were searched for relevant RCTs published between January 2011 and January 3, 2021. Cohen's Q Test for heterogeneous effects was used to determine the appropriateness of fixed versus random effects models.

Results

Twenty-two studies met inclusion criteria. Meta-analysis of relative risk of mortality between treatment and placebo groups in the in-hospital, and perioperative settings was not significant. However, the risk of mortality is significantly lower in the treatment versus placebo group when TXA was given as loading dose only. Ten of the 11 studies evaluating perioperative use of TXA included in systematic review found significantly lower blood loss in the treatment compared with placebo groups, but results of meta-analysis showed no significant difference. Results of meta-analysis indicate that the risk of venous thromboembolism (VTE) in the in-hospital treatment group is greater than that of the placebo. In subset analysis of studies using only a single loading dose, there were no significant differences in VTE.

Conclusions

Systematic review supports TXA benefits are most evident when given shortly after injury and meta-analysis supports TXA reduces mortality as a single loading dose. Systematic review supports perioperative use of TXA when large volume blood loss is anticipated. Meta-results showed no significant difference in risk of thromboembolism in single-dose TXA treatment compared with placebo. These findings suggest that TXA is safe and effective for control of traumatic bleeding.

Contribution of Various Types of Transfusion to Acute and Delayed Intracerebral Hemorrhage Injury

Intracerebral hemorrhage (ICH) is the second most prevalent type of stroke, after ischemic stroke, and has exceptionally high morbidity and mortality rates. After spontaneous ICH, one primary goal is to restrict hematoma expansion, and the second is to limit brain edema and secondary injury. Various types of transfusion therapies have been studied as treatment options to alleviate the adverse effects of ICH etiopathology. The objective of this work is to review transfusions with platelets, fresh frozen plasma (FFP), prothrombin complex concentrate (PCC), and red blood cells (RBCs) in patients with ICH. Furthermore, tranexamic acid infusion studies have been included due to its connection to ICH and hematoma expansion. As stated, the first line of therapy is limiting bleeding in the brain and hematoma expansion. Platelet transfusion is used to promote recovery and mitigate brain damage, notably in patients with severe thrombocytopenia. Additionally, tranexamic acid infusion, FFP, and PCC transfusion have been shown to affect hematoma expansion rate and volume. Although there is limited available research, RBC transfusions have been shown to cause higher tissue oxygenation and lower mortality, notably after brain edema, increases in intracranial pressure, and hypoxia. However, these types of transfusion have varied results depending on the patient, hemostasis status/blood thinner, hemolysis, anemia, and complications, among other variables. Inconsistencies in published results on various transfusion therapies led us to review the data and discuss issues that need to be considered when establishing future guidelines for patients with ICH.

Tranexamic Acid for Adult Patients with Spontaneous Intracerebral Hemorrhage: A Systematic Review with Meta-analysis

BACKGROUND

The effects of tranexamic acid on spontaneous intracerebral hemorrhage in reducing hematoma expansion and mortality as well as its role in thromboembolic complications and in the improvement of functional outcomes remain substantially uncertain.

OBJECTIVE

The objective of this systematic review was to evaluate the efficacy and safety of tranexamic acid in patients with spontaneous intracerebral hemorrhage.

METHODS

Several databases were searched from inception up to 20 June, 2021. We included randomized controlled trials that compared tranexamic acid with placebo or no treatment for the management of intracerebral hemorrhage. The primary outcomes were hematoma expansion and 90-day mortality. The secondary outcomes were hemorrhagic volume change, thromboembolic complications, and functional outcomes.

RESULTS

Overall, six trials with 2800 patients were included in this meta-analysis. Tranexamic acid was associated with a reduced risk of hematoma expansion (relative risk 0.87, 95% confidence interval [CI] 0.77-0.99, p = 0.03, I² = 0%, six trials with 2800 participants) and a lessening of hematoma volume change (mean difference - 1.28, 95% CI - 2.44 to - 0.12; p = 0.03; I² = 0%, four trials with 2626 participants), without a corresponding higher rate of major thromboembolic complications (relative risk 1.20, 95% CI 0.85-1.69; p = 0.80; I² = 0%, five trials with 2759 participants). The present analysis also demonstrated that tranexamic acid had no effect on reducing 90-day mortality (relative risk 1.02, 95% CI 0.88-1.19; p = 0.80; I² = 0%, five trials with 2770 participants).

CONCLUSIONS

In adults with spontaneous intracerebral hemorrhage, tranexamic acid reduced the risk of intracerebral hemorrhage growth compared with the control. The effects on 90-day mortality remained inconclusive. Further studies should report death within 24 h and death due to bleeding whenever possible.

The Function of Tranexamic Acid to Prevent Hematoma Expansion After Intracerebral Hemorrhage: A Systematic Review and Meta-Analysis From Randomized Controlled Trials

Objectives: The clinical results caused by spontaneous intracerebral hemorrhage (ICH) are disastrous to most patient. As tranexamic acid (TXA) has been proved to decrease the influence of ICH, we conducted this research to explore the function of TXA for the prognosis of ICH compared with placebo.

Methods: We searched MEDLINE, Embase, Cochrane Library, and Clinicaltrials.gov for randomized controlled trials (RCTs) that were performed to evaluate TXA vs. placebo for ICH up to February 2021. The data were assessed by Review Manager 5.3 software. The risk ratio (RR) and mean difference were analyzed using dichotomous outcomes and continuous outcomes, respectively, with a fixed effect model.

Results: We collected 2,479 patients from four RCTs. Then, we took the change of hematoma volume, modified Rankin Scale (mRS), and adverse events as evaluation standard of the treatment for ICH. Through statistical analysis, we found that there is no obvious hematoma expansion effect after the application of TXA (RR = 1.05), and we proceeded the quantitative analysis of percentage change in hematoma volume from baseline, indicating that TXA could inhibit the expansion of hematoma volume (RR = −2.02) compared with placebo. However, according to the outcomes of mRS (0–1, RR = 1.04; 0–2, RR = 0.96), TXA cannot improve neurological functional prognosis. As for the security outcomes—mortality (RR = 1.02), thromboembolic events (RR = 0.99), neurological deterioration (RR = 0.92), infection (RR = 0.86), and craniotomy (RR = 0.41), there seems exist no statistical difference between TXA and placebo.

Conclusions: TXA has an advantage in the aspect of preventing hematoma expansion compared with placebo for ICH, but cannot illustrate the efficacy of TXA in improving neurological functional prognosis, which still needs more researches with large sample sizes. Moreover, for safety, we did not find obvious statistical difference between TXA and placebo.

Tranexamic acid in non-traumatic intracranial bleeding: a systematic review and meta-analysis

Non-traumatic intracranial bleeding (NTIB), comprising subarachnoid hemorrhage (SAH) and intra-cranial bleeding (ICH) is a significant public health concern. Tranexamic acid (TXA) is a promising treatment with benefits yet to be fully demonstrated. We conducted a systematic review and meta-analysis on the impact of TXA on mortality in NTIB. We searched the PubMed, Cochrane Library, Google Scholar and ScienceDirect databases for studies reporting mortality data following the use of TXA in NTIB for comparisons with a control group. We computed random-effect meta-analysis on estimates of risk and sensitivity analyses. We computed meta-regression to examine the putative effects of the severity of NTIB, sociodemographic data (age, sex), and publication date. Among potentially 10,008 articles, we included 15 studies representing a total of 4883 patients: 2455 receiving TXA and 2428 controls; 1110 died (23%) during the follow-up. The meta-analysis demonstrated a potential of 22% decrease in mortality for patients treated by TXA (RR = 0.78, 95%CI 0.58-0.98, p = 0.002). Meta-regression did not demonstrate any influence of the severity of NTIB, age, sex, length of treatment or date of publication. Sensitivity analyses confirmed benefits of TXA on mortality. TXA appears to be a therapeutic option to reduce non-traumatic intracranial bleeding mortality, particularly in patients with SAH.