Tranexamic acid in trauma: how should we use it?

Tranexamic acid is associated with post-injury mortality in a resource-limited trauma system: Findings from the epidemiology and outcomes of prolonged trauma care cohort study

BACKGROUND

Injury-related deaths claim millions of lives annually, with severe hemorrhage a leading cause. This study assesses tranexamic acid (TXA) administered within 3 h post-injury on mortality in trauma patients.

STUDY DESIGN AND METHODS

We conducted secondary database analysis of EpiC, a multicenter, prospective cohort of trauma patients in South Africa. We compared mortality between severely injured patients at risk for traumatic hemorrhage receiving TXA within 3 h post-injury versus untreated patients. Inverse probability of treatment weighting adjusted for confounders, and multivariate logistic regression assessed 24-h mortality, with extended secondary outcome analyses.

RESULTS

Of 3607 analyzed patients, 502 received TXA within 3 h. TXA reduced 24-h mortality by 38% (marginal odds ratio [mOR], 0.62; 95% confidence interval [CI], 0.49-0.78) versus untreated patients. Similar reductions were observed for longer-term mortality. Subgroup analyses revealed reduced mortality when TXA was given within 2 h post-injury (mOR, 0.57; 95% CI, 0.45-0.73), doses of 1 g of TXA within 3 h (mOR, 0.73; 95% CI, 0.56-0.94), and those with the highest risk of hemorrhage (mOR, 0.40; 95% CI, 0.30-0.53). The 24-h mortality reduction was significant for patients with penetrating injury (mOR, 0.58; 95% CI, 0.43-0.78) but not for blunt injury patients. Sensitivity analyses confirmed the robustness of these findings, with TXA consistently reducing mortality odds by 28%-39% across subgroups.

DISCUSSION

Early TXA administration significantly reduced mortality in trauma patients, especially with penetrating injuries and those with the highest risk of hemorrhage. One-gram dosing was as effective as higher doses, and mortality reduction was notable when TXA was given within 2 h post-injury. These findings support TXA use in resource-limited trauma protocols.

Tranexamic acid in the management of traumatic brain injury: a systematic review and meta-analysis with trial sequential analysis

INTRODUCTION

Traumatic brain injury is a leading cause of death and disability. Tranexamic acid, an antifibrinolytic agent, holds the potential for managing intracranial hemorrhages secondary to traumatic brain injury. However, its efficacy and safety remain subjects of ongoing debate.

OBJECTIVE

To better clarify the efficacy and safety of tranexamic acid in that context and to evaluate the need for further studies.

METHODS

We conducted a comprehensive search of seven electronic databases, eight study repositories, and tertiary sources between January 2021 and 2022 for randomized controlled trials involving victims of traumatic brain injury aged 15 or older who received tranexamic acid versus placebo or standard care. The primary outcomes were all-cause mortality and hemorrhagic complications during treatment. This review incorporated elements of PRISMA guidelines, Cochrane's Risk of Bias assessment, and GRADE to assess evidence quality. Sensitivity analyses were also conducted.

RESULTS

Out of 6,958 references retrieved, 14 of the 17 randomized controlled trials were analyzed, encompassing a total of 15,017 patients. Analyses for all-cause mortality did not reach statistical significance (RR= 0.95, 95%CI= 0.88-1.02 | trial sequential analysis RR= 0.95, 95%CI= 0.87-1.03). However, the analysis of hemorrhagic complications during treatment showed statistical significance for progressive intracranial hemorrhage (RR= 0.82, 95%CI= 0.68-0.99 | trial sequential analysis RR= 0.82, 95%CI= 0.38-1.78). Analyses of secondary outcomes, namely unfavorable neurological outcome and other adverse effects, did not demonstrate statistical significance.

CONCLUSION

Tranexamic acid use did not demonstrate efficacy based on all-cause mortality but showed a favorable safety profile. Additional clinical trials may shed light on remaining clinical uncertainties. Prospero database registration: CRD42021221949.

Emergency treatment of pelvic ring injuries: state of the art

High energy pelvic injuries sustain significant mortality rates, due to acute exsanguination and severe associated injuries. Managing the hemodynamically unstable trauma patient with a bleeding pelvic fracture still forms a major challenge in acute trauma care. Various approaches have been applied through the last decades. At present the concept of Damage Control Resuscitation (DCR) is universally accepted and applied in major trauma centers internationally. DCR combines hemostatic blood transfusions to restore blood volume and physiologic stability, reduced crystalloid fluid administration, permissive hypotension, and immediate hemorrhage control by operative or angiographic means. Different detailed algorithms and orders of hemostatic procedures exist, without clear consensus or guidelines, depending on local traditions and institutional setups. Fracture reduction and immediate stabilization with a binder constitute the basis for angiography and embolization (AE) or pelvic packing (PP) in the hemodynamically unstable patient. AE is time consuming and may not be available 24/7, whereas PP offers a quick and technically easy procedure well suited for the patient in extremis. Resuscitative endovascular balloon occlusion of the aorta (REBOA) has also been described as a valuable adjunct in hemostatic non-responders, but merely constitute a bridge to surgical or angiographic hemostasis and its definitive role in DCR is not yet clearly established. A swift algorithmic approach to the hemodynamically unstable pelvic injury patient is required to achieve optimum results. The present paper summarizes the available literature on the acute management of the bleeding pelvic trauma patient, with emphasis on initial assessment and damage control resuscitation including surgical and angiographic hemostatic procedures. Furthermore, initial treatment of open fractures and associated injuries to the nervous and genitourinary system is outlined.

Does Tranexamic Acid Administration Increase the Risk of Thromboembolism?

Introduction Hemorrhage following trauma is one of the leading causes of death worldwide. Venous thromboembolism (VTE) is a common complication of an increased coagulable state, and the risk of VTE following the administration of tranexamic acid (TXA), an antifibrinolytic agent, is still controversial. Our aim is to understand whether there is any association between the administration of TXA and the risk of VTE development. Methods A retrospective cohort study enrolled trauma patients presenting to a level 1 trauma center who received TXA at King Abdulaziz Medical City (KAMC), a tertiary hospital in Riyadh, Saudi Arabia, between 2016 and 2020. Variables included were patients' demographics, comorbidities, laboratory investigations, TXA's route of administration, date of administration, and dose. Finally, the development of VTE in the form of deep vein thrombosis (DVT) or PE and those who died were evaluated. Results A total of 361 adult trauma patients who received TXA were included in the study. Most were males (90.3%) with an average age of 33 years and had a normal BMI (43.3%). Nine patients (2.5%) developed DVT, one of whom died, and five patients (1.4%) developed PE, with no recorded deaths. Conclusion The risk of VTE following the administration of TXA remains controversial and yet to be clearly demonstrated. In this study, there was no significant association between TXA administration and the risk of developing VTE. More research with a larger sample size is needed to identify and recognize any significant risk factors for developing such a condition.

Unravelling the Antifibrinolytic Mechanism of Action of the 1,2,3-Triazole Derivatives

A new family of antifibrinolytic drugs has been recently discovered, combining a triazole moiety, an oxadiazolone, and a terminal amine. Two of the molecules of this family have shown activity that is greater than or similar to that of tranexamic acid (TXA), the current antifibrinolytic gold standard, which has been associated with several side effects and whose use is limited in patients with renal impairment. The aim of this work was to thoroughly examine the mechanism of action of the two ideal candidates of the 1,2,3-triazole family and compare them with TXA, to identify an antifibrinolytic alternative active at lower dosages. Specifically, the antifibrinolytic activity of the two compounds (1 and 5) and TXA was assessed in fibrinolytic isolated systems and in whole blood. Results revealed that despite having an activity pathway comparable to that of TXA, both compounds showed greater activity in blood. These differences could be attributed to a more stable ligand-target binding to the pocket of plasminogen for compounds 1 and 5, as suggested by molecular dynamic simulations. This work presents further evidence of the antifibrinolytic activity of the two best candidates of the 1,2,3-triazole family and paves the way for incorporating these molecules as new antifibrinolytic therapies.

Does tranexamic acid have a positive effect on the outcome of older multiple trauma patients on antithrombotic drugs? An analysis using the TraumaRegister DGU®

Background

Acute hemorrhage is one of the most common causes of death in multiple trauma patients. Due to physiological changes, pre-existing conditions, and medication, older trauma patients are more prone to poor prognosis. Tranexamic acid (TXA) has been shown to be beneficial in multiple trauma patients with acute hemorrhage in general. The relation of tranexamic acid administration on survival in elderly trauma patients with pre-existing anticoagulation is the objective of this study. Therefore, we used the database of the TraumaRegister DGU® (TR-DGU), which documents data on severely injured trauma patients.

Methods

In this retrospective analysis, we evaluated the TR-DGU data from 16,713 primary admitted patients with multiple trauma and age > =50 years from 2015 to 2019. Patients with pre-existing anticoagulation and TXA administration (996 patients, 6%), pre-existing anticoagulation without TXA administration (4,807 patients, 28.8%), without anticoagulation as premedication but TXA administration (1,957 patients, 11.7%), and without anticoagulation and TXA administration (8,953 patients, 53.6%) were identified. A regression analysis was performed to investigate the influence of pre-existing antithrombotic drugs and TXA on mortality. A propensity score was created in patients with pre-existing anticoagulation, and matching was performed for better comparability of patients with and without TXA administration.

Results

Retrospective trauma patients who underwent tranexamic acid administration were older and had a higher ISS than patients without tranexamic acid donation. Predicted mortality (according to the RISC II Score) and observed mortality were higher in the group with tranexamic acid administration. The regression analysis showed that TXA administration was associated with lower mortality rates within the first 24 h in older patients with anticoagulation as premedication. The propensity score analysis referred to higher fluid requirement, higher requirement of blood transfusion, and longer hospital stay in the group with tranexamic acid administration. There was no increase in complications. Despite higher transfusion volumes, the tranexamic acid group had a comparable all-cause mortality rate.

Conclusion

TXA administration in older trauma patients is associated with a reduced 24-h mortality rate after trauma, without increased risk of thromboembolic events. There is no relationship between tranexamic acid and overall mortality in patients with anticoagulation as premedication. Considering pre-existing anticoagulation, tranexamic acid may be recommended in elderly trauma patients with acute bleeding.

Thromboembolic Complications Following Perioperative Tranexamic Acid Administration

INTRODUCTION

The antifibrinolytic tranexamic acid (TXA) may reduce death in trauma; however, outcomes associated with TXA use in patients without proven hyperfibrinolysis remain unclear. We analyzed the associations of empirically administered TXA, hypothesizing that TXA use would correlate to lower transfusion totals but increased thromboembolic complications.

METHODS

This retrospective cohort study compared trauma patients started on massive transfusion protocol at a Level I trauma center from 2016 to 2021 who either did or did not receive TXA. Our primary outcome was in-hospital mortality. Venous thromboembolism (VTE; pulmonary embolism or deep vein thrombosis), transfusion volumes, and coagulation measures were considered secondarily. Descriptive statistics, univariate analyses, and multivariable logistic regression were used to evaluate differences in outcomes.

RESULTS

TXA patients presented with lower systolic blood pressure (100 versus 119.5 mmHg, P = 0.009), trended toward higher injury severity (ISS of 25 versus 20, P = 0.057), and were likelier to have undergone thoracotomy or laparotomy (89 versus 71%, P = 0.002). After adjusting for age, mechanism, presenting vitals, and operation, TXA was not significantly associated with mortality or VTE. TXA patients had larger volumes of packed red blood cells, platelets, and plasma transfused within 4- and 24-h (P ≤ 0.002). No differences in clot stability, captured via thromboelastography, were noted.

CONCLUSIONS

Despite no differences in mortality or VTE between patients who did and did not receive TXA, there were significant differences in transfusion totals. TXA patients had worse presenting physiology and likely had more severe bleeding. This absence of adverse outcomes supports TXA's safety. Nevertheless, further inquiry into the precise mechanism of TXA may help guide its empiric use, allowing for more targeted application.

Tranexamic acid use in meningioma surgery - A systematic review and meta-analysis

Tranexamic Acid (TXA) has been used in medical and surgical practice to reduce haemorrhage. The aim of this review was to evaluate the effect of TXA use on intraoperative and postoperative outcomes of meningioma surgery. A systematic review and meta-analysis was conducted in accordance with the PRISMA statement and registered in PROSPERO (CRD42021292157). Six databases were searched up to November 2021 for phase 2-4 control trials or cohort studies, in the English language, examining TXA use during meningioma surgery. Studies ran outside of dedicated neurosurgical departments or centres were excluded. Risk of bias was assessed using the Cochrane Risk of Bias 2 tool. Random effects meta-analysis were performed to delineate differences in operative and postoperative outcomes. Four studies (281 patients) were included. TXA use significantly reduced intraoperative blood loss (mean difference 315.7 mls [95% confidence interval [CI] -532.8, -98.5]). Factors not affected by TXA use were transfusion requirement (odds ratio = 0.52; 95% CI 0.27, 0.98), operation time (mean difference = -0.2 h; 95% CI -0.8, 0.4), postoperative seizures (Odds Ratio [OR] = 0.88; 95% CI 0.31, 2.53), hospital stay (mean difference = -1.2; 95% CI -3.4, 0.9) and disability after surgery (OR = 0.50; 95% CI 0.23, 1.06). The key limitations of this review were the small sample size, limited data for secondary outcomes and a lack of standardised method for measuring blood loss. TXA use reduces blood loss in meningioma surgery, but not transfusion requirement or postoperative complications. Larger trials are required to investigate the impact of TXA on patient-reported postoperative outcomes.

Crosstalk between Inflammation and Hemorrhage/Coagulation Disorders in Primary Blast Lung Injury

Primary blast lung injury (PBLI), caused by exposure to high-intensity pressure waves from explosions in war, terrorist attacks, industrial production, and life explosions, is associated with pulmonary parenchymal tissue injury and severe ventilation insufficiency. PBLI patients, characterized by diffused intra-alveolar destruction, including hemorrhage and inflammation, might deteriorate into acute respiratory distress syndrome (ARDS) with high mortality. However, due to the absence of guidelines about PBLI, emergency doctors and rescue teams treating PBLI patients rely on experience. The goal of this review is to summarize the mechanisms of PBLI and their cross-linkages, exploring potential diagnostic and therapeutic targets of PBLI. We summarize the pathophysiological performance and pharmacotherapy principles of PBLI. In particular, we emphasize the crosstalk between hemorrhage and inflammation, as well as coagulation, and we propose early control of hemorrhage as the main treatment of PBLI. We also summarize several available therapy methods, including some novel internal hemostatic nanoparticles to prevent the vicious circle of inflammation and coagulation disorders. We hope that this review can provide information about the mechanisms, diagnosis, and treatment of PBLI for all interested investigators.

An Unexpected 12.6 Centimeter Nail in the Thorax Damaging Vital Structures: A Case Report “Nailed It”

We report a patient who was referred to the emergency room with pulmonary complaints and where a computed tomography (CT) scan showed an unexpected 12.6 cm nail in the thorax penetrating part of the left pulmonary upper lobe, the left pulmonary artery, the left main bronchus, and the descending aorta, which had been in situ for at least three days. The quickly deteriorating patient had to be transferred to a tertiary academic hospital where the nail was successfully surgically removed. The comprehensive description of this unique case with a discussion of the critical decision moments could render insights into the management of challenging trauma cases.

Serine proteases mediate leukocyte recruitment and hepatic microvascular injury in the acute phase following extended hepatectomy

OBJECTIVE

Post-hepatectomy liver failure (PHLF) is the main limitation of extended liver resection. The molecular mechanism and the role of leukocytes in the development of PHLF remain to be unveiled. We aimed to address the impact of serine proteases (SPs) on the acute phase after liver resection by intravitally analyzing leukocyte recruitment and changes in hemodynamics and microcirculation of the liver.

METHODS

C57BL/6 mice undergoing 60% partial hepatectomy were treated with aprotinin (broad-spectrum SP inhibitor), tranexamic acid (plasmin inhibitor), or vehicle. Sham-operated animals served as controls. In vivo fluorescence microscopy was used to quantify leukocyte-endothelial interactions immediately after, as well as 120 min after partial hepatectomy in postsinusoidal venules, along with measurement of sinusoidal perfusion rate and postsinusoidal shear rate. Recruitment of leukocytes, neutrophils, T cells, and parameters of liver injury were assessed in tissue/blood samples.

RESULTS

Leukocyte recruitment, sinusoidal perfusion failure rate, and shear rate were significantly increased in mice after 60% partial hepatectomy compared to sham-operated animals. The inhibition of SPs or plasmin significantly attenuated leukocyte recruitment and improved the perfusion rate in the remnant liver. ICAM-1 expression and neutrophil recruitment significantly increased after 60% partial hepatectomy and were strongly reduced by plasmin inhibition.

CONCLUSIONS

Endothelial activation and leukocyte recruitment in the liver in response to the increment of sinusoidal shear rate were hallmarks in the acute phase after liver resection. SPs mediated leukocyte recruitment and contributed to the impairment of sinusoidal perfusion in an ICAM-1-dependent manner in the acute phase after liver resection.

The optimal regimen, efficacy and safety of tranexamic acid and aminocaproic acid to reduce bleeding for patients after total hip arthroplasty: A systematic review and Bayesian network meta-analysis

OBJECTIVES

We aimed to evaluate the optimal regimen, efficacy and safety of tranexamic acid (TXA) and aminocaproic acid (EACA) for patients after total hip arthroplasty (THA).

METHODS

The network meta-analysis was guided by the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guideline. The outcomes were total blood loss, transfusion rates, hemoglobin (HB) drop, and risk for pulmonary embolism (PE) or deep vein thrombosis (DVT). Subgroup analyses were performed among most effective regimens to determine the influences of timing and number of doses.

RESULTS

A total of 56 eligible RCTs with different regimens were assessed. For reducing total blood loss, all high doses of TXA and EACA except high dose of intra-articular (IA) TXA, as well as medium dose of combination of intravenous and intra-articular (combined IV/IA) TXA were most effective. All high doses of TXA, as well as medium dose of combined IV/IA TXA did not show inferiority in reducing transfusion rates and HB drop compared with other regimens. No regimens showed higher risk for PE or DVT compared with placebo, and no statistical differences were seen among most effective regimens in subgroup analyses.

CONCLUSIONS

As effective as high doses of EACA and TXA, medium dose (20-40 mg/kg or 1.5-3.0 g) of combined IV/IA TXA was enough to control bleeding for patients after THA without increasing risk for PE/DVT. TXA was at least 5 times more potent than EACA. Timing and number of doses had few influences on blood conserving efficacy.

LEVEL OF EVIDENCE

Level I.

Comparison of the Utilization of Tranexamic Acid and Tourniquet Use in Total Knee Arthroplasty: A Retrospective Case Series

Introduction: Total knee arthroplasty (TKA) carries a high risk for significant blood loss due to bone cuts and extensive soft tissue involvement in the knee region. The use of tranexamic acid (TXA) or a tourniquet are two methods commonly employed to prevent significant blood loss and avoid the need for blood transfusion. TXA has been shown to reduce both intraoperative and postoperative bleeding as well as the probability that a patient will require a blood transfusion. The purpose of this study is to compare the efficacy of TXA and tourniquet use, both alone and in combination, in reducing blood loss during TKA.

Methods: Data for this retrospective cohort study were obtained by searching records of patients who underwent TKA at a tertiary care center from January 2019 to October 2020. Data from 526 subjects were available. A chart review was conducted to determine if the patient received TXA only, tourniquet only, or both TXA and tourniquet during the TKA procedure. Primary outcomes for this study including procedure length in minutes, estimated blood loss in cubic centimeters, and total infusion pressor (phenylephrine) administered intraoperatively in milligrams were recorded for the study. Data were summarized using means and standard errors. Statistical methods used for analysis include one-way ANOVA, probability plots, the Shapiro-Wilk test for normality, the Kruskal-Wallis test, and Tukey’s test.

Results: Data were available for 526 subjects. 122 subjects received tourniquet only (Tourniquet group), 104 received intravenous (IV) TXA only, 264 received both tourniquet and IV TXA (Tourniquet + TXA), and 36 received neither tourniquet nor TXA (None). The groups did not significantly differ in procedure length (p = 0.140) or infusion pressor total (p > 0.20). The groups did significantly differ in estimated blood loss (p < 0.001). Subjects who did not receive either TXA or tourniquet had significantly more blood loss than the Tourniquet and Tourniquet + TXA groups. Similarly, the TXA group had significantly more blood loss than both the Tourniquet and Tourniquet + TXA groups.

Conclusion: This study supports the conclusion that the use of a tourniquet is superior to the use of TXA in reducing intraoperative blood loss during TKA. All groups that underwent TKA using a tourniquet, either alone or in combination with TXA, exhibited significantly lower levels of blood loss compared to the control (no intervention) group.

Risk of Mortality among Patients with Gastrointestinal Bleeding with Early and Late Treatment with Tranexamic Acid: A Population-Based Cohort Study

Tranexamic acid (TXA) is an antifibrinolytic pharmacological agent, but its use in gastrointestinal bleeding remains contentious. Moreover, studies on the timing of TXA administration are limited. We examined whether early TXA administration reduced the risk of mortality in patients with gastrointestinal bleeding in a Taiwanese population. We used the National Health Insurance Research Database to identify patients diagnosed with gastrointestinal bleeding with early and late TXA treatment. We defined early treatment as initial TXA treatment in an emergency department and late treatment as initial TXA treatment after hospitalization. Mortality within 52 weeks was the primary outcome. A multivariable analysis using a multiple Cox regression model was applied for data analysis. Propensity score matching (PSM) was performed to reduce the potential for bias caused by measured confounding variables. Of the 52,949 selected patients with gastrointestinal bleeding, 5127 were assigned to either an early or late TXA treatment group after PSM. The incidence of mortality was significantly decreased during the first and fourth weeks (adjusted HR (aHR): 0.65, 95% CI: 0.56−0.75). A Kaplan−Meier curve revealed a significant decrease in cumulative incidence of mortality in the early TXA treatment group (log-rank test: p < 0.0001). Multiple Cox regression analysis revealed significantly lower mortality in the early TXA treatment group compared with the late treatment group (aHR: 0.64, 95% CI: 0.57−0.73). Thromboembolic events were not significantly associated with early or late TXA treatment (aHR: 1.03, 95% CI: 0.94−1.12). A Kaplan−Meier curve also revealed no significant difference in either venous or arterial events (log-rank test: p = 0.3654 and 0.0975, respectively). In conclusion, early TXA treatment was associated with a reduced risk of mortality in patients with gastrointestinal bleeding compared with late treatment, without an increase in thromboembolic events. The risk of rebleeding and need for urgent endoscopic intervention require further randomized clinical trials.

Pro-Con Debate: Viscoelastic Hemostatic Assays Should Replace Fixed Ratio Massive Transfusion Protocols in Trauma

Major trauma patients at risk of traumatic coagulopathy are commonly treated with early clotting factor replacement to maintain hemostasis and prevent microvascular bleeding. In the United States, trauma transfusions are often dosed by empiric, low-ratio massive transfusion protocols, which pair plasma and platelets in some ratio relative to the red cells, such as the "1:1:1" combination of 1 units of red cells, 1 unit of plasma, and 1 donor's worth of pooled platelets. Empiric transfusion increases the rate of overtransfusion when unnecessary blood products are administered based on a formula and not on at patient's hemostatic profile. Viscoelastic hemostatic assays (VHAs) are point-of-care hemostatic assays that provided detailed information about abnormal clotting pathways. VHAs are used at many centers to better target hemostatic therapies in trauma. This Pro/Con section will address whether VHA guidance should replace empiric fixed ratio protocols in major trauma.

Systemic prednisolone versus topical tranexamic acid for prevention of rebleeding in patients with traumatic hyphema: A randomized clinical trial

PURPOSE

To compare the efficacy of systemic prednisolone and topical tranexamic acid (TA) on the rate of rebleeding in patients with macroscopic traumatic hyphema (MTH).

METHOD

In a randomized clinical trial, patients with MTH were randomized to receive oral prednisolone (OP group) or topical TA drops (TA group). Comprehensive ophthalmic examinations including slit lamp examination and fundoscopy, intraocular pressure (IOP), best-corrected visual acuity (BCVA) and check for rebleeding were performed in all cases.

RESULTS

Ninety eyes of 90 patients were included, and 45 patients were allocated into each group. Age, sex, IOP, BCVA and grade of hyphema were not different between groups. Rebleeding in the TA group (2 patients, 4.4%) occurred less frequently than in the OP group (7 patients, 15.6%), but this difference did not reach statistical significance (P=0.081). However, there was a significant difference between the two groups over time in terms of absorption of the MTH (P<0.001).

CONCLUSION

Topical TA appears promising in the management of macroscopic traumatic hyphema.

Effectiveness of Tranexamic Acid in Reducing Hemorrhage in Isolated Blunt Solid Organ Injury

Introduction: There is considerable interest in the use of tranexamic acid (TXA) for the control of hemorrhages in trauma patients. Multiple recent studies found that TXA used in the setting of a suspected significant hemorrhage in trauma patients significantly reduced mortality. To date, there are no cited studies that specifically address hemorrhage due to solid organ injury (i.e., kidneys, liver, and spleen) and TXA use in humans. Our current research addresses whether TXA is effective in reducing complications and mortality from traumatic hemorrhage in the setting of a specific solid organ injury.

Methods: We conducted a retrospective observational cohort study utilizing propensity score matching at Arrowhead Regional Medical Center (ARMC) from February 1, 2009 to February 1, 2019. This study period marks five years prior to and five years after February 1, 2004, which is the date when TXA first started to be used at ARMC in the management of traumatic hemorrhage. We compared for statistical difference between corresponding injury types in the TXA and non-TXA groups.

Results: Before the propensity matching, there were 123 patients who received TXA and 118 patients who did not. After propensity match for age and injury severity score (ISS), 35 patients were included in each group. We found no statistically significant difference between TXA and non-TXA treatment groups in terms of mortality at 24 hours (p-value=0.4945), mortality at 48 hours (p-value=0.4945), and mortality at 28 days (p-value=0.7426). We found no statistically significant difference between the need for interventional radiology intervention at 72 hours (p-value=0.3932), surgical intervention at 72 hours (p-value=0.2123) and possible TXA related complications (p-value=1).

Conclusion: Although prior studies showed that TXA use in the setting of trauma may be beneficial, the specific candidate-selection criteria remain unclear. The results of our study suggest that the benefit from TXA in the setting of the isolated splenic, liver, and or renal injury may be negligible. We believe that this first-of-its-kind study adds to the growing body of knowledge about the utility of TXA and helps guide patient-selection criteria.

Efficacy and safety of the second in-hospital dose of tranexamic acid after receiving the prehospital dose: double-blind randomized controlled clinical trial in a level 1 trauma center

Background

Prehospital administration of tranexamic acid (TXA) to injured patients is increasing worldwide. However, optimal TXA dose and need of a second infusion on hospital arrival remain undetermined. We investigated the efficacy and safety of the second in-hospital dose of TXA in injured patients receiving 1 g of TXA in the prehospital setting. We hypothesized that a second in-hospital dose of TXA improves survival of trauma patients.

Methods

A prospective, double-blind, placebo-controlled randomized, clinical trial included adult trauma patients receiving 1 g of TXA in the prehospital settings. Patients were then blindly randomized to Group I (second 1-g TXA) and Group II (placebo) on hospital arrival. The primary outcome was 24-h (early) and 28-day (late) mortality. Secondary outcomes were thromboembolic events, blood transfusions, hospital length of stay (HLOS) and organs failure (MOF).

Results

A total of 220 patients were enrolled, 110 in each group. The TXA and placebo groups had a similar early [OR 1.000 (0.062–16.192); p = 0.47] and late mortality [OR 0.476 (95% CI 0.157–1.442), p = 0.18].The cause of death (n = 15) was traumatic brain injury (TBI) in 12 patients and MOF in 3 patients. The need for blood transfusions in the first 24 h, number of transfused blood units, HLOS, thromboembolic events and multiorgan failure were comparable in the TXA and placebo groups. In seriously injured patients (injury severity score > 24), the MTP activation was higher in the placebo group (31.3% vs 11.10%, p = 0.13), whereas pulmonary embolism (6.9% vs 2.9%, p = 0.44) and late mortality (27.6% vs 14.3%, p = 0.17) were higher in the TXA group but did not reach statistical significance.

Conclusion

The second TXA dose did not change the mortality rate, need for blood transfusion, thromboembolic complications, organ failure and HLOS compared to a single prehospital dose and thus its routine administration should be revisited in larger and multicenter studies.

Trial registration

ClinicalTrials.gov Identifier: NCT03846973.

Tranexamic acid administration and pulmonary embolism in combat casualties with orthopaedic injuries

Objectives:

In combat casualty care, tranexamic acid (TXA) is administered as part of initial resuscitation effort; however, conflicting data exist as to whether TXA contributes to increased risk of venous thromboembolism (VTE). The purpose of this study is to determine what factors increase risk of pulmonary embolism after combat-related orthopaedic trauma and whether administration of TXA is an independent risk factor for major thromboembolic events.

Setting:

United States Military Trauma Centers.

Patients:

Combat casualties with orthopaedic injuries treated at any US military trauma center for traumatic injuries sustained from January 2011 through December 2015. In total, 493 patients were identified.

Intervention:

None.

Main Outcome Measures:

Occurrence of major thromboembolic events, defined as segmental or greater pulmonary embolism or thromboembolism-associated pulseless electrical activity.

Results:

Regression analysis revealed TXA administration, traumatic amputation, acute kidney failure, and hypertension to be associated with the development of a major thromboembolic event for all models. Injury characteristics independently associated with risk of major VTE were Injury Severity Score 23 or greater, traumatic amputation, and vertebral fracture. The best performing model utilized had an area under curve  = 0.84, a sensitivity=0.72, and a specificity=0.84.

Conclusions:

TXA is an independent risk factor for major VTE after combat-related Orthopaedic injury. Injury factors including severe trauma, major extremity amputation, and vertebral fracture should prompt suspicion for increased risk of major thromboembolic events and increased threshold for TXA use if no major hemorrhage is present.

Level of evidence:

III, Prognostic Study

Novel resuscitation strategies in patients with a pelvic fracture

Patients with a pelvic ring injury and hemodynamic instability can be challenging to manage with high rates of morbidity and mortality rates. Protocol-based resuscitation strategies are critical to successfully manage these potentially severely injured patients in a well-coordinated manner. While some aspects of treatment may vary slightly from institution to institution, it is critical to identify pelvic injuries and their associated injuries expediently. The first step at the scene of injury or in the trauma resuscitation bay should be the immediate application of a circumferential pelvic sheet or binder, initiation of physiologically optimal fluid resuscitation in the form 1:1:1 (pRBC:FFP:platelets) or whole blood, and to consider TXA as a safe adjunct to treat coagulopathy. Providers should have a very low threshold for emergent operative intervention in the form of pelvic external fixation and/or pelvic packing. This occurs in addition to simultaneous interventions addressing the other possible sources of bleeding in patients demonstrating signs of hemorrhagic shock and failure to respond to early resuscitation and external pelvic tamponade. Finally, while arterial injury is only present in a small percentage of patients with a pelvic ring injury, percutaneous vascular intervention with selective angiography and REBOA have been shown to be efficacious for patients with clinical indicators of arterial injury or who remain hemodynamically unstable despite external pelvic tamponade and packing to address venous bleeding. They should be performed when as early as possible for patients in true extremis limit further hemorrhage and allow resuscitation efforts to continue.

Management of life-threatening hemoptysis in the ICU

Life-threatening hemoptysis is commonly encountered in the ICU and its management can be challenging even for experienced clinicians. Depending on the etiology and severity, one can tailor the treatment modality and therapeutic intervention(s). The grading of severity of hemoptysis varies greatly in the literature; however, unlike hemorrhage in other scenarios, small amounts of blood can significantly impair oxygenation and ventilation leading to cardiovascular collapse. Importantly, the initial evaluation and management should focus on airway and hemodynamic stabilization along with maintenance of oxygenation and ventilation. In this review, we discuss commonly encountered etiologies, vascular anatomy, diagnostic evaluation, and therapeutic interventions. We examine the evolving trends in etiologies of life-threating hemoptysis over the years. The role of flexible and rigid bronchoscopy as both a diagnostic and therapeutic modality is explored, as well as the use and indications of several bronchoscopic techniques, such as topical hemostatic agents, endobronchial tamponade, and tranexamic acid (TXA). In addition, we assess the use of multi-row detector computed tomography as the initial rapid diagnostic method of choice and its use in planning for definitive treatment. The efficacy and long-term results of bronchial artery embolization (BAE) are evaluated, as well as indications for surgical intervention. Furthermore, the importance of a multidisciplinary approach is emphasized. The necessary interplay between intensivists, consultative services, and radiologists is described in detail and an algorithmic management strategy incorporating the above is outlined. Given the complexity in management of life-threatening hemoptysis, this paper aims to summarize the available diagnostic and therapeutic methods and provide a standardized approach for the management of patients with this often difficult to treat condition.

Reversing Rivaroxaban Anticoagulation as Part of a Multimodal Hemostatic Intervention in a Polytrauma Animal Model

BACKGROUND

Life-threatening bleeding requires prompt reversal of the anticoagulant effects of factor Xa inhibitors. This study investigated the effectiveness of four-factor prothrombin complex concentrate in treating trauma-related hemorrhage with rivaroxaban-anticoagulation in a pig polytrauma model. This study also tested the hypothesis that the combined use of a low dose of prothrombin complex concentrate plus tranexamic acid and fibrinogen concentrate could improve its subtherapeutic effects.

METHODS

Trauma (blunt liver injury and bilateral femur fractures) was induced in 48 anesthetized male pigs after 30 min of rivaroxaban infusion (1 mg/kg). Animals in the first part of the study received prothrombin complex concentrate (12.5, 25, and 50 U/kg). In the second part, animals were treated with 12.5 U/kg prothrombin complex concentrate plus tranexamic acid or plus tranexamic acid and fibrinogen concentrate. The primary endpoint was total blood loss postinjury. The secondary endpoints (panel of coagulation parameters and thrombin generation) were monitored for 240 min posttrauma or until death.

RESULTS

The first part of the study showed that blood loss was significantly lower in the 25 U/kg prothrombin complex concentrate (1,541 ± 269 ml) and 50 U/kg prothrombin complex concentrate (1,464 ± 108 ml) compared with control (3,313 ± 634 ml), and 12.5 U/kg prothrombin complex concentrate (2,671 ± 334 ml, all P < 0.0001). In the second part of the study, blood loss was significantly less in the 12.5 U/kg prothrombin complex concentrate plus tranexamic acid and fibrinogen concentrate (1,836 ± 556 ml, P < 0.001) compared with 12.5 U/kg prothrombin complex concentrate plus tranexamic acid (2,910 ± 856 ml), and there were no early deaths in the 25 U/kg prothrombin complex concentrate, 50 U/kg prothrombin complex concentrate, and 12.5 U/kg prothrombin complex concentrate plus tranexamic acid and fibrinogen concentrate groups. Histopathologic analyses postmortem showed no adverse events.

CONCLUSIONS

Prothrombin complex concentrate effectively reduced blood loss, restored hemostasis, and balanced thrombin generation. A multimodal hemostatic approach using tranexamic acid plus fibrinogen concentrate enhanced the effect of low doses of prothrombin complex concentrate, potentially reducing the prothrombin complex concentrate doses required for effective bleeding control.

EDITOR’S PERSPECTIVE

Efficacy and safety of tranexamic acid in hip fracture surgery: A comparative study of 613 patients

BACKGROUND

Blood loss is a major concern in the frail elderly patient undergoing hip fracture surgery. The objective of this study was to investigate the efficacy of tranexamic acid in reducing blood loss and allogenic blood transfusions. The study also investigated the safety profile by comparing rates of thromboembolic events.

METHODS

A total of 613 patients with hip fractures were included in the study. Patients received 1g of tranexamic acid on induction of anaesthesia. Postoperative haemoglobin was measured on day one. Blood loss was calculated, and blood transfusion was recorded.

RESULTS

Tranexamic acid use resulted in a higher mean postoperative haemoglobin (110.3 ± 15.9 vs 106.8 ± 16.2; p = 0.023) and reduced mean estimated blood loss (571.3 ± 150.4 vs 678.3 ± 201.2; p = 0.001). There was also a significantly reduced number of transfusions in tranexamic acid group (13% vs 28%; p = 0.002). There was no difference in rates of deep vein thrombosis (4 vs 3; p = 0.98) or pulmonary embolism (2 vs 2; p = 1).

CONCLUSION

The use of tranexamic acid is effective in reduction of blood loss and rates of blood transfusion, without an apparent increase in adverse thromboembolic events.

Clinical observation and dermoscopy evaluation of fractional CO2 laser combined with topical tranexamic acid in melasma treatments

BACKGROUND

Melasma is an acquired refractory pigmentary disorder, which is a skin disease that predominantly affects females. This investigation aims to assess the efficacy of a low-power fractional CO₂ laser combined with tranexamic acid (TXA) for melasma topical treatment with MASI and dermoscopy.

MATERIALS AND METHODS

A randomized comparative split-face study was performed. Each treatment interval was 3 weeks with four times in total. At the same time, we applied TXA solution twice a day. Assessments were made by the MASI score of the melasma area severity index, and the dermoscopy performance was collected and analyzed.

RESULTS

After treatments, the patient MASI score decreased significantly. Compared with the baseline, the MASI score was significantly lower than that of control group (P < .05), and the decrease ratio was higher than that of controls. Dermoscopy examination results verified that all lesions performed reticuloglobular pattern, granular, or punctate, with no structural pigmentation and obvious capillary dilation. After comprehensive treatments, the pigmentation area displayed lighter chroma, the follicle pore uniformity was completely improved, and the capillary dilation was significantly reduced.

CONCLUSIONS

Low-power fractional CO₂ laser combined with topical TXA solution is a comparatively effective and safe method for melasma treatment. TXA could reduce the dilation of blood vessels.

Is Preoperative Administration of Tranexamic Acid Effective on Blood Loss Reduction in Mandibular Fracture Surgeries? A Triple-Blind Randomized Clinical Trial

PURPOSE

Hemorrhage is one of the significant factors that cause adverse reactions and complications during trauma management. This study aimed to investigate the effectiveness of preoperative tranexamic acid (TXA) administration on intraoperative blood loss in mandibular fracture surgeries.

MATERIALS AND METHODS

The authors implemented a triple blinded randomized clinical trial. All healthy young patients who suffered from bilateral displaced mandibular angle and body fractures were included in this study. All operations were performed using open reduction and internal fixation by the same surgical team. The eligible subjects were randomly divided into 2 equal groups. The anesthesiology staff administered the intravenous TXA (20 mg/kg) to the intervention group and 20 mL of intravenous normal saline (0.09%) in the control group, 30 minutes preoperatively. The study outcome variables included intraoperative blood loss and hemoglobin loss. The data were statistically analyzed in SPSS, version 20 (SPSS Inc, Chicago, IL).

RESULTS

Fifty patients, including 31 males (62%) and 19 females (38%), with the mean age of 28 ± 5.6 years were studied. The mean blood loss was 360.57 ± 173.5 mL and 560.9 ± 248.07 mL in the TXA and control groups, respectively. This difference was statistically significant (P = .008). In addition, the mean drop in hemoglobin value was 0.91 ± 0.33 mg/dL in the intervention group and 1.44 ± 0.45 mg/dL in the control group, with a significant difference (P = .001). No adverse effect was observed in the TXA cases.

CONCLUSIONS

TXA is a safe and effective drug for reducing intraoperative blood loss in patients who underwent mandibular fracture open reduction and internal fixation surgeries.

Comparison of the effectiveness and safety of intravenous and topical regimens of tranexamic acid in complex tibial plateau fracture: a retrospective study

Background

Previous studies have demonstrated the effectiveness and safety of tranexamic acid (TXA) in orthopedic surgery. However, no study has investigated TXA in complex tibial plateau fracture surgery. Therefore, the purpose of this study was to confirm the safety and effectiveness of i.v. (intravenous) TXA and topical TXA.

Material and methods

This was a retrospective analysis of prospectively collected data. The control group received an equal amount of placebo (physiological saline solution); the i.v. group received 1.0 g TXA by intravenous injection before the tourniquet was inflated and before the surgical incision was closed, and the topical group received 3.0 g TXA in 75 mL of physiological saline solution 5 min prior to the final tourniquet release. Perioperative blood loss, vascular events, wound complications, and adverse reactions were compared among the three groups. The pain, knee function, and quality of life (QoL) assessments were based on their corresponding scoring systems.

Results

Baseline data were comparable for all groups. The i.v. group showed the best results for total blood loss (TBL) and hidden blood loss (HBL) (424.5 ± 49.4 mL and 219.3 ± 33.4 mL, respectively, all P values < 0.001). Patients in the i.v. group had lesser real Hb decrease than those in the control group (0.9 vs 1.5, P<0.001) and topical group (0.9 vs 1.2, P = 0.026). The blood coagulation level as measured using fibrinolysis (D-dimer) was lower in the i.v. group than in the control and topical groups on POD1 and POD3; however, this difference was not significant; the fibrin-degradation products also showed a similar trend. Patients in the topical group experienced less pain than those in the control group on POD2, POD4, and PO6W. The VAS pain score was 3.6 vs. 4.4 (POD2, P<0.05), 2.8 vs 3.3 (POD4, P<0.05), and 2.1 vs. 2.6 (PO6W, P<0.001) in the topical group vs control group, respectively. No significant differences were identified in vascular events, wound complications, adverse reactions, knee function, and QoL among the three groups.

Conclusion

To our knowledge, this is the first study that showed both i.v. TXA and topical TXA are safe and effective for complex tibial plateau fractures. The i.v. regimen effectively reduced blood loss during the perioperative period, whereas patients under the topical regimen had less vascular events, wound complications, and a lower incidence of adverse reactions compared to those in the i.v. group.

Trial registration

The trial was registered in the Chinese Clinical Trial Registry (ChiCTR-TRC-1800017754, retrospectively registered from 2018 to 01-01).

Expert consensus on the diagnosis and treatment of thrombocytopenia in adult critical care patients in China

Thrombocytopenia is a common complication of critical care patients. The rates of bleeding events and mortality are also significantly increased in critical care patients with thrombocytopenia. Therefore, the Critical Care Medicine Committee of Chinese People's Liberation Army (PLA) worked with Chinese Society of Laboratory Medicine, Chinese Medical Association to develop this consensus to provide guidance for clinical practice. The consensus includes five sections and 27 items: the definition of thrombocytopenia, etiology and pathophysiology, diagnosis and differential diagnosis, treatment and prevention.

The never ending success story of tranexamic acid in acquired bleeding

Tranexamic acid (TXA) is an anti-fibrinolytic agent that acts by inhibiting plasminogen activation and fibrinolysis. Although its first clinical use dates back more than 50 years, this hemostatic agent is still the object of intense clinical and developmental research. In particular, renewed interest in TXA has arisen following evidence that it has a beneficial effect in reducing blood loss in a variety of medical and surgical conditions at increased risk of bleeding. Given this characteristic, TXA is currently considered a mainstay of Patient Blood Management programs aimed at reducing patients’ exposure to allogeneic blood transfusion. Importantly, recent large randomized controlled trials have consistently documented that the use of TXA confers a survival advantage in a number of globally critical clinical conditions associated with acute bleeding, including traumatic injury and post-partum hemorrhage, without increasing the thromboembolic risk.

Early intravenous administration of tranexamic acid ameliorates intestinal barrier injury induced by neutrophil extracellular traps in a rat model of trauma/hemorrhagic shock

BACKGROUND

Early intravenous administration of tranexamic acid has been shown to protect the intestinal barrier after a model of trauma-hemorrhagic shock in the rat, but the potential mechanism remains unclear. Our previous studies have demonstrated that neutrophil extracellular traps contribute to the intestinal barrier dysfunction during sepsis and other critical conditions. Meanwhile, there are high levels of neutrophil infiltration in the intestine during trauma-hemorrhagic shock. Here, we hypothesized that neutrophil extracellular trap formation played a vital role during trauma-hemorrhagic shock-induced intestinal injury and that tranexamic acid, a serine protease inhibitor, may inhibit neutrophil extracellular trap formation and protect intestinal barrier function in trauma-hemorrhagic shock.

METHODS

A model of trauma-hemorrhagic shock in male rats was established. The rats were divided into 6 groups: (1) sham group; (2) trauma-hemorrhagic shock group; (3) trauma-hemorrhagic shock + DNase I group; (4) trauma-hemorrhagic shock + tranexamic acid group; (5) trauma-hemorrhagic shock + tranexamic acid (different time) group; and (6) trauma-hemorrhagic shock + tranexamic acid (different doses) group. The DNase I solution was injected intravenously to disrupt neutrophil extracellular traps immediately after the trauma-hemorrhagic shock model was completed. After 24 hours, the small intestine and blood were collected for analysis. Human neutrophils were harvested and incubated with phorbol-12-myristate-13-acetate or tranexamic acid, generation of reactive oxygen species, and key proteins expression were detected.

RESULTS

Trauma-hemorrhagic shock induced the formation of intestinal neutrophil extracellular traps and disrupted the intestinal tight junction proteins. Clearing of neutrophil extracellular traps by DNase I resulted in increased expression of tight junction proteins and alleviated the intestinal injury. Early intravenous tranexamic acid administration (1 hour after trauma-hemorrhagic shock) decreased neutrophil extracellular trap formation and prevented tight junction protein disruption compared to the non-tranexamic acid group; however, after delayed administration of tranexamic acid (6 hours), there were no changes in neutrophil extracellular trap formation and intestinal injuries compared to the non-tranexamic acid group. Furthermore, tranexamic acid inhibited neutrophil extracellular trap formation and protected the intestinal barrier in a dose-dependent manner and high-dose (20 mg/kg) treatment of tranexamic acid showed a better effect compared with the therapeutic dose (10 mg/kg). The results of thromboelastography demonstrated that the R and K values in the high-dose group decreased (R, 1.85 ± 0.14 vs 3.87 ± 0.16 minutes, P < .001; K, 0.95 ± 0.04 vs 1.48 ± 0.07 minutes, P < .001), accompanied by a decrease in LY30, indicating that treatment with a high dose of tranexamic acid may cause hypercoagulability and shutdown of fibrinolysis. In addition, less neutrophil extracellular trap formation was detected in neutrophils incubated with neutrophils via an reactive oxygen species-dependent pathway.

CONCLUSION

We first demonstrated a novel role of neutrophil extracellular traps in the pathophysiology of intestinal barrier dysfunction during trauma-hemorrhagic shock. Notably, early but not delayed intravenous administration of tranexamic acid effectively inhibits neutrophil extracellular trap formation and protects intestinal barrier function. Therefore, these results suggested a potential theoretic intervention for the protection of the intestinal barrier during trauma-hemorrhagic shock. In such a process, tranexamic acid appears to regulate neutrophil extracellular trap formation via the classic reactive oxygen species/mitogen-activated protein kinase pathway.

The TREATT Trial (TRial to EvaluAte Tranexamic acid therapy in Thrombocytopenia): safety and efficacy of tranexamic acid in patients with haematological malignancies with severe thrombocytopenia: study protocol for a double-blind randomised controlled trial

Background

Patients with haematological malignancies often develop thrombocytopenia as a consequence of either their disease or its treatment. Platelet transfusions are commonly given to raise a low platelet count and reduce the risk of clinical bleeding (prophylaxis) or stop active bleeding (therapy). Recent studies have shown that many patients continue to experience bleeding despite the use of prophylactic platelet transfusions. Tranexamic acid is an anti-fibrinolytic, which reduces the breakdown of clots formed in response to bleeding. Anti-fibrinolytics have been shown to prevent bleeding, decrease blood loss and use of red cell transfusions in elective and emergency surgery, and are used widely in these settings. The aim of this trial is to test whether giving tranexamic acid to patients receiving treatment for haematological malignancies reduces the risk of bleeding or death and the need for platelet transfusions.

Methods

This is a multinational randomised, double-blind, placebo-controlled, parallel, superiority trial. Patients will be randomly assigned to receive tranexamic acid (given intravenously or orally) or a matching placebo in a 1:1 ratio, stratified by site. Patients with haematological malignancies receiving intensive chemotherapy or stem cell transplantation (or both) who are at least 18 years of age and expected to become severely thrombocytopenic for at least 5 days will be eligible for this trial. The primary outcome of the trial is the proportion of patients who died or had bleeding of World Health Organization grade 2 or above during the first 30 days of the trial. We will measure the rates of bleeding daily by using a short, structured assessment of bleeding, and we will record the number of transfusions given to patients. We will assess the risk of arterial and venous thrombosis for 120 days from the start of trial treatment.

Discussion

This trial will assess the safety and efficacy of using prophylactic tranexamic acid during a period of intensive chemotherapy and associated thrombocytopenia in people with haematological disorders.

Trial registration

This study was prospectively registered on Current Controlled Trials on 25 March 2015 (ISRCTN73545489) and is also registered on ClinicalTrials.gov (NCT03136445).

Electronic supplementary material

The online version of this article (10.1186/s13063-019-3663-2) contains supplementary material, which is available to authorized users.

Trauma-targeted delivery of tranexamic acid improves hemostasis and survival in rat liver hemorrhage model

BACKGROUND

Trauma-associated hemorrhage and coagulopathy remain leading causes of mortality. Such coagulopathy often leads to a hyperfibrinolytic phenotype where hemostatic clots become unstable because of upregulated tissue plasminogen activator (tPA) activity. Tranexamic acid (TXA), a synthetic inhibitor of tPA, has emerged as a promising drug to mitigate fibrinolysis. TXA is US Food and Drug Administration-approved for treating heavy menstrual and postpartum bleeding, and has shown promise in trauma treatment. However, emerging reports also implicate TXA for off-target systemic coagulopathy, thromboembolic complications, and neuropathy.

OBJECTIVE

We hypothesized that targeted delivery of TXA to traumatic injury site can enable its clot-stabilizing action site-selectively, to improve hemostasis and survival while avoiding off-target effects. To test this, we used liposomes as a model delivery vehicle, decorated their surface with a fibrinogen-mimetic peptide for anchorage to active platelets within trauma-associated clots, and encapsulated TXA within them.

METHODS

The TXA-loaded trauma-targeted nanovesicles (T-tNVs) were evaluated in vitro in rat blood, and then in vivo in a liver trauma model in rats. TXA-loaded control (untargeted) nanovesicles (TNVs), free TXA, or saline were studied as comparison groups.

RESULTS

Our studies show that in vitro, the T-tNVs could resist lysis in tPA-spiked rat blood. In vivo, T-tNVs maintained systemic safety, significantly reduced blood loss and improved survival in the rat liver hemorrhage model. Postmortem evaluation of excised tissue from euthanized rats confirmed systemic safety and trauma-targeted activity of the T-tNVs.

CONCLUSION

Overall, the studies establish the potential of targeted TXA delivery for safe injury site-selective enhancement and stabilization of hemostatic clots to improve survival in trauma.

Structural studies of plasmin inhibition

Plasminogen (Plg) is the zymogen form of the serine protease plasmin (Plm), and it plays a crucial role in fibrinolysis as well as wound healing, immunity, tissue remodeling and inflammation. Binding to the targets via the lysine-binding sites allows for Plg activation by plasminogen activators (PAs) present on the same target. Cellular uptake of fibrin degradation products leads to apoptosis, which represents one of the pathways for cross-talk between fibrinolysis and tissue remodeling. Therapeutic manipulation of Plm activity plays a vital role in the treatments of a range of diseases, whereas Plm inhibitors are used in trauma and surgeries as antifibrinolytic agents. Plm inhibitors are also used in conditions such as angioedema, menorrhagia and melasma. Here, we review the rationale for the further development of new Plm inhibitors, with a particular focus on the structural studies of the active site inhibitors of Plm. We compare the binding mode of different classes of inhibitors and comment on how it relates to their efficacy, as well as possible future developments.

The safest and most efficacious route of tranexamic acid administration in total joint arthroplasty: A systematic review and network meta-analysis

INTRODUCTION

Blood loss in Total Joint Arthroplasty can be significant and often under-estimated. This study aims to investigate the safety and efficacy of different routes of tranexamic acid (TXA) administration in reducing blood transfusion after Total Hip Arthroplasty (THA) and Total Knee Arthroplasty (TKA). The secondary aim is to find the safest and most efficacious route and dose of TXA.

MATERIAL AND METHODS

PubMed, Embase, Cochrane library, China National Knowledge Infrastructure, and OpenGrey were systemically searched for randomised controlled trials investigating the efficacy and/or safety of TXA for THA and/or TKA. Network meta-analysis, comparing the number of transfusion and deep vein thrombosis (DVT) among different interventions, was performed using a multivariate meta-regression model with random-effects, adopting a frequentist approach.

RESULTS

211 publications (20,639 individuals) were included. For outcome of transfusion, all interventions showed significantly lower transfusion rates compared to placebo. When compared to placebo, TXA via intra-venous and topical showed statistically significant lowest risk ratio (RR = 0.11, 95CI: 0.03, 0.41). For safety, TXA via topical showed relatively lowest risk ratio (RR = 0.75, 95CI 0.44, 1.30). TXA via topical and intra-articular had the highest but statistically insignificant RR (RR = 1.10, 95%CI: 0.51, 2.38). Therefore, current studies did not reveal any significant safety issue in using TXA.

CONCLUSION

All forms of TXA administration showed significantly lower transfusion rate compared to control. There is a trend towards better efficacy with intra-venous and topical. In patients with higher risk of thrombosis, physicians may consider topical alone for its best safety profile.

Effects of tranexamic acid on reducing blood loss in pelvic trauma: A randomised double-blind placebo controlled study

BACKGROUND

Management of pelvic trauma is complicated with patients' instability and remains high in skeletal injuries. The patients usually are young and in middle age and the management of bleeding is more important. The aim of this study is to assess the effects of Tranexamic Acid in Reducing Blood Loss in pelvic trauma: A Randomised Double-Blind Placebo Controlled Study.

METHOD AND MATERIALS

In this randomized clinical trial study 106 patients with Pelvic Trauma (PT) were randomly divided into two groups. The case group received 1 g Intravenous TXA for loading dose and 3 dose per 8 h for the maintenance and control group received only serum 0.9% N.S (Normal Saline) or placebo. The Hemoglobin (Hb), Hematocrit (HCT), Pulse Rate (PR) and Blood Pressure (BP) was checked at admission, 24 h, 48 h and 72 h after admission.

RESULTS

From 106 patients 61(%57.54) male and 45 (%42.46) female patients enrolled to the study. The mean age was 48.14 ± 13.54 and the range was 18-60 years old. There was no difference between two groups based on Blood Pressure at admission, 24 h, 48 h and 72 h after admission. There was a significant difference between two groups in 24 h, 48 h and 72 h after admission based on Hb and HCT amount.

CONCLUSION

based on our findings it appears that TXA can reduce bleeding amount in the first, second and third 24 h after surgery based on Hb and HCT without any effect on systolic and diastolic BP and PR. In other hand no side effect reported by any patients.

Tranexamic Acid for Adults with Melasma: A Systematic Review and Meta-Analysis

Objective

Melasma is a highly prevalent, chronic, and pigmentary disorder. This systematic review aims to evaluate the efficacy and safety of tranexamic acid (TA) for the treatment of adults with melasma.

Methods

We independently searched 3 databases from beginning to 26 April, 2018. The study included 21 eligible trials. Two writers extracted data at the same time independently. Study outcomes were calculated by standardized mean differences (SMD) with 95% confidence intervals (CIs). All statistical analyses were performed using Review Manager Version 5.3 and STATA Version 15.1.

Results

The combined results showed that the use of TA was associated with reduced Melasma Area and Severity Index (MASI) and Melanin Index (MI). No significant difference in Erythema Index (EI) was observed with TA treatment. Side effects were minor, with a few cases reporting mild gastrointestinal reaction, oligomenorrhoea, hypopigmentation, urticarial rash, and skin irritation xerosis.

Conclusion

The meta-analysis suggested that TA treatment appeared to be a promising therapeutic approach for melasma.

Benefits of the tranexamic acid in head trauma with no extracranial bleeding: a prospective follow-up of 180 patients

INTRODUCTION

Tranexamic acid (TXA) is one of the debated therapies in the management of traumatic brain injury (TBI). We conducted this study to evaluate the benefits of TXA in TBI on the mortality and its safety in these patients.

METHODS

This was a prospective randomized open-label trial including all patients, aged at 18 years or older, hospitalized in the emergency room during a 13-month period, for TBI. After the realization of the body CT scan, the patients were included if they had intracranial bleeding, and were then randomized according to their medical file number to receive or not the TXA. The eligibility criteria were based on the uncertainty principle, patients with significant extracranial bleeding were excluded since there was evidence that TXA improve their outcome.

RESULTS

We enrolled 180 patients aged at 42 ± 20 years, with an 88% men-proportion. Subarachnoid haemorrhage was the most frequent lesion in the brain CT-scan (67.5%). After randomization, 96 patients were in the TXA group (53%). Demographic data, clinical, biological and radiological features were statistically comparable in the two groups of patients ('TXA' and 'noTXA'). The needs of transfusion or neurosurgery, the mortality rate, the in-hospital length of stay and the dependency at 28-post-traumatic day were similar in the two groups of patients. However, pulmonary embolism was statistically more frequent in 'TXA' group (11.5 versus 2.4%, p = 0.02).

CONCLUSION

TXA is an interesting treatment in haemorrhagic shock. Its efficiency in head trauma is still debated and controversial. Its impact on the mortality and the needs of transfusion or surgery were not demonstrated in this study. Nevertheless, its safety worth to be studied in larger samples as we found a higher rate of pulmonary embolism in the treated group.

Blood products and procoagulants in traumatic bleeding: use and evidence

PURPOSE OF REVIEW

Death from uncontrolled haemorrhage is one of the leading causes of trauma-related mortality and is potentially preventable. Advances in understanding the mechanisms of trauma-induced coagulopathy (TIC) have focused attention on the role of blood products and procoagulants in mitigating the sequelae of TIC and how these therapies can be improved.

RECENT FINDINGS

A host of preclinical and clinical studies have evaluated blood product availability and efficacy in trauma. Recently published randomized controlled trials have investigated the ratio of platelet:plasma:red cell transfusion and the role of early cryoprecipitate in trauma. Demand for readily available plasma has led to changes particularly in the use of thawed group A plasma. Furthermore, ex-vivo and early clinical work has demonstrated variations in the haemostatic activity of different plasma, platelet and whole blood products. A number of multicentre trials are in progress aiming to answer key questions regarding tranexamic acid, procoagulant factor and fibrinogen concentrates and their effect on trauma outcomes.

SUMMARY

There are promising results from ex-vivo studies in manufacturing and storage of blood products to optimize haemostatic activity and availability, particularly with alternative plasma and platelet products and whole blood. There is an urgent need for these products needs to be tested prospectively.

Measuring fibrinolysis: from research to routine diagnostic assays

Development and standardization of fibrinolysis methods have progressed more slowly than coagulation testing and routine high-throughput screening tests for fibrinolysis are still lacking. In laboratory research, a variety of approaches are available and are applied to understand the regulation of fibrinolysis and its contribution to the hemostatic balance. Fibrinolysis in normal blood is slow to develop. For practical purposes plasminogen activators can be added to clotting plasma, or euglobulin prepared to reduce endogenous inhibitors, but results are complicated by these manipulations. Observational studies to identify a 'fibrinolysis deficit' have concluded that excess fibrinolysis inhibitors, plasminogen activator inhibitor 1 (PAI-1) or thrombin-activatable fibrinolysis inhibitor (TAFI), zymogen or active enzyme, may be associated with an increased risk of thrombosis. However, results are not always consistent and problems of adequate standardization are evident with these inhibitors and also for measurement of fibrin degradation products (D-dimer). Few methods are available to investigate fibrinolysis under flow, or in whole blood, but viscoelastic methods (VMs) such as ROTEM and TEG do permit the contribution of cells, and importantly platelets, to be explored. VMs are used to diagnose clinical hyperfibrinolysis, which is associated with high mortality. There is a debate on the usefulness of VMs as a point-of-care test method, particularly in trauma. Despite the difficulties of many fibrinolysis methods, research on the fibrinolysis system, taking in wider interactions with hemostasis proteins, is progressing so that in future we may have more complete models and better diagnostic methods and therapeutics.

Fibrinolysis in trauma: a review

Fibrinolytic dysregulation is an important mechanism in traumatic coagulopathy. It is an incompletely understood process that consists of a spectrum ranging from excessive breakdown (hyperfibrinolysis) and the shutdown of fibrinolysis. Both hyperfibrinolysis and shutdown are associated with excess mortality and post-traumatic organ failure. The pathophysiology appears to relate to endothelial injury and hypoperfusion, with several molecular markers identified in playing a role. Although there are no universally accepted diagnostic tests, viscoelastic studies appear to offer the greatest potential for timely identification of patients presenting with fibrinolytic dysregulation. Treatment is multimodal, involving prompt hemorrhage control and resuscitation, with controversy surrounding the use of antifibrinolytic drug therapy. This review presents the current evidence on the pathophysiology, diagnostic challenges, as well as the management of this hemostatic dysfunction.

LEVEL OF EVIDENCE

Level III.

Coagulation factor concentrate-based therapy for remote damage control resuscitation (RDCR): a reasonable alternative?

The concept of remote damage control resuscitation (RDCR) is still in its infancy and there is significant work to be done to improve outcomes for patients with life-threatening bleeding secondary to injury. The prehospital phase of resuscitation is critical and if shock and coagulopathy can be rapidly minimized before hospital admission this will very likely reduce morbidity and mortality. The optimum transfusion strategy for these patients is still highly debated and the potential implications of the recently published pragmatic, randomize, optimal platelet, and plasma ratios trial (PROPPR) for RDCR have been reviewed. Identifying the appropriate transfusion strategy is mandatory before adopting prehospital hemostatic resuscitation strategies. An alternative approach is based on the early administration of coagulation factor concentrates combined with the antifibrinolytic tranexamic acid (TXA). The three major components to this approach in the context of RDCR target the following steps to achieve hemostasis: 1) stop (hyper)fibrinolysis; 2) support clot formation; and 3) increase thrombin generation. Strong evidence exists for the use of TXA. The data from the prospective fibrinogen in trauma induced coagulopathy (FIinTIC) study will inform on the prehospital use of fibrinogen in bleeding trauma patients. Deficits in thrombin generation may be addressed by the administration of prothrombin complex concentrates. Handheld point-of-care devices may be able to support and guide the prehospital and remote use of intravenous hemostatic agents including coagulation factor concentrates along with clinical presentation, assessment, and the extent of bleeding. Combinations may even be more effective for bleeding control. More studies are urgently needed.

Tranexamic acid leads to paradoxical coagulation changes during cardiac surgery: a pilot rotational thromboelastometry study

BACKGROUND

Tranexamic acid (TXA) is increasingly used during major surgery with the goal to reduce excessive bleeding, transfusion requirements, and reexploration. Our aim was to examine the effect of TXA on coagulation at different times during cardiac surgery using rotational thromboelastometry.

MATERIALS AND METHODS

Nineteen adult males (EuroSCORE 4-5) were recruited consecutively for first-time cardiopulmonary bypass (CPB) surgery. Ten patients received TXA at anesthesia and nine received no TXA. Rotational thromboelastometry analysis occurred before anesthesia (baseline), after sternotomy, after CPB-heparinization and surgery, and after protamine administration-sternal closure.

RESULTS

A median sternotomy had no effect on clot time (CT), formation, amplitude, or lysis in non-TXA patients. In contrast, TXA patients had twofold prolonged clotting time (all-tests) and ∼30% reduced FIBTEM (A5-30) and maximum clot firmness, indicating reduced thrombin generation and lower clot fibrinogen. After CPB, CTs in both groups were prolonged, possibly linked to overheparinization. In addition, TXA patients had significantly decreased EXTEM (A5-30), suggesting lower clot strength. After protamine-sternal closure, clotting time remained prolonged in both groups, and TXA patients had a persistently 25%-33% lower FIBTEM (A5-30) and maximum clot firmness. TXA patients also had significantly reduced platelet numbers (37% from baseline), which continued Days 1 and 2. Maximum clot lysis was <10% indicating little or no hyperfibrinolysis during cardiac surgery.

CONCLUSIONS

In this nonrandomized, nonblinded, observational trial, patients in the TXA group displayed prolonged CTs and clot fibrinogen (FIBTEM A5-30) after sternotomy, decreased clot strength (EXTEM) after CPB/surgery, and acute thrombocytopenia after protamine-sternal closure. There was no significant decrease in clot lysis, questioning the need for TXA in this medium-risk group.

Tranexamic Acid Update in Trauma

Following results from the CRASH-2 trial, tranexamic acid (TXA) gained considerable interest for the treatment of hemorrhage in trauma patients. Although TXA is effective at reducing mortality in patients presenting within 3 hours of injury, optimal dosing, timing of administration, mechanism, and pharmacokinetics require further elucidation. The concept of fibrinolysis shutdown in hemorrhagic trauma patients has prompted discussion of real-time viscoelastic testing and its potential role for appropriate patient selection. The results of ongoing clinical trials will help establish high-quality evidence for optimal incorporation of TXA in mature trauma networks in the United States and abroad.

Bleeding related to disturbed fibrinolysis

The components and reactions of the fibrinolysis system are well understood. The pathway has fewer reactants and interactions than coagulation, but the generation of a complete quantitative model is complicated by the need to work at the solid‐liquid interface of fibrin. Diagnostic tools to detect disease states due to malfunctions in the fibrinolysis pathway are also not so well developed as is the case with coagulation. However, there are clearly a number of inherited or acquired pathologies where hyperfibrinolysis is a serious, potentially life‐threatening problem and a number of antifibrinolytc drugs are available to treat hyperfibrinolysis. These topics will be covered in the following review.

Tranexamic Acid Use in United States Trauma Centers: A National Survey

Tranexamic acid (TXA) is an antifibrinolytic agent that is listed as an essential medication by the World Health Organization for traumatic hemorrhage. We determined United States–based surgeons’ familiarity with TXA and their use of TXA. An online survey was sent to the 1291 attending surgeon members of a national trauma organization. The survey was organized into three general parts: respondent demographics, perceptions of TXA, and experience with TXA. The survey was completed by 35 per cent of members. TXA was available at 89.1 per cent of centers. Experience with TXA was variable: 38.0 per cent use regularly, 24.9 per cent use it 1 to 2 times per year, 12.3 per cent use it rarely, and 24.7 per cent had never used it. Among surgeons who had used TXA, 77.1 per cent noted that TXA had reduced bleeding, but 22.9 per cent indicated that it had not. Reasons for not routinely using TXA included uncertain clinical benefit (47.7%) and unfamiliarity (31.5%). Finally, 90.5 per cent of respondents indicated that are looking toward national organizations to develop practice guidelines. TXA is widely available in civilian United States trauma centers. Although a majority of surveyed surgeons had used TXA, only 38 per cent use TXA regularly for significant traumatic hemorrhage; principal reasons for this are uncertainty regarding clinical benefit and unfamiliarity with the drug. National guidelines are sought.