Comparison of coagulation and fibrinolysis in Irish Wolfhounds and age-matched control dogs using tissue plasminogen activator-augmented viscoelastic testing.

OBJECTIVE: To determine if Irish Wolfhounds (IWs), like other sighthounds, are hyperfibrinolytic compared with nonsighthound dogs using 2 native and tissue plasminogen activator (tPA)-enhanced viscoelastic assays, one that is whole blood-based (viscoelastic coagulation monitor [VCM]) and the other that is plasma-based thromboelastography (TEG). DESIGN: Cohort study. SETTING: University teaching hospital. ANIMALS: A convenience sample of 27 IWs recruited from the Irish Wolfhound Association of New England Specialty and the local community, and 27 healthy, age-matched, large-breed control dogs. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Blood samples including CBC, biochemistry, traditional coagulation, and viscoelastic testing were collected from IWs and control dogs. Twelve IWs had viscoelastic testing. IWs had lower fibrinogen concentrations (215.5 ± 57.8 vs 251.4 ± 64.5 mg/dL, P = 0.034) and formed weaker clots on both whole-blood VCM and plasma TEG assays (maximum clot firmness [VCM-MCF] = 39.4 [25.1-48.8] vs 48.5 [34.6-57.3], P = 0.0042; maximum amplitude [TEG-MA] = 22.7 [14.7-33.6] vs 32.2 [26.9-42.0], P < 0.0001). IWs were hyperfibrinolytic compared with control dogs on VCM whole-blood assays, with 25 U/mL tPA (lysis at 30 min [VCM-LI30] = 68.1 [0-100] vs\ 99.9 [63.3-100], P = 0.0009; lysis at 45 min [VCM-LI45] = 31.0 [0-100] vs 98.1 [38.4-100], P = 0.0002) but hypofibrinolytic compared with controls on TEG plasma assays with 50 U/mL tPA (lysis at 30 min [TEG-LY30] = 45.7 [4.6-94.6] vs 93.7 [12.3-96.5], P = 0.0004; lysis at 60 min [TEG-LY60] = 68.7 [29.7-96.8] vs 95.7 [34.4-97.6], P = 0.0003). Minimal fibrinolysis was measured on whole-blood VCM or plasma TEG assays without the addition of tPA, and there were no differences between the 2 groups. CONCLUSIONS: Weaker clots were found in IWs than control dogs. With the addition of tPA, IWs had evidence of hyperfibrinolysis on whole-blood VCM assays and hypofibrinolysis on plasma TEG assays compared with control dogs. Without the addition of tPA, however, both groups of dogs showed minimal fibrinolysis on viscoelastic testing.

Use of crushed tranexamic acid tablets in water for paediatric patients with bleeding disorders.

BACKGROUND: Ε-Aminocaproic acid oral solution (EACA OS) is the only commercially available antifibrinolytic for patients who cannot swallow tablets. Insurance denials and high costs remain barriers to its use. OBJECTIVES: To determine the safety and efficacy of crushed tranexamic acid tablets in water (cTXAw) for children with bleeding disorders. METHODS: We retrospectively reviewed records of children (<10 years) with bleeding disorders who received cTXAw or EACA OS from 1 December 2018, through 31 July 2022, at Mayo Clinic (Rochester, Minnesota). Bleeding outcomes were defined according to ISTH criteria. RESULTS: Thirty-two patients were included (median age, 3 years; male, n = 23). Diagnoses were VWD (n = 17), haemophilia (n = 5), FVII deficiency (n = 3), inherited platelet disorder (n = 4), ITP (n = 2), and combined FV and FVII deficiencies (n = 1). Thirty-two courses of cTXAw (monotherapy 24/32; mean duration 6 days) and fifteen courses of EACA (monotherapy 12/15; mean duration 5 days) were administered. No surgical procedures (n = 28) were complicated by bleeding. Of the 19 bleeding events, 16 had effective haemostasis, two had no reported outcome, and one had no response. cTXAw and EACA were equally effective in preventing and treating bleeding (p value > .1). No patients had adverse effects. Eight of 19 patients (42%) who were initially prescribed EACA OS did not receive it because of cost or insurance denial. The estimated average wholesale price of one treatment was $94 for cTXAw and $905 for EACA OS. CONCLUSIONS: CTXAw appears to be an effective, safe, and low-cost alternative option to EACA OS for young children with bleeding disorders.

Procedural outcomes in children with mild type 1 von Willebrand disease.

Background: In patients with mild type 1 von Willebrand disease (VWD), treatment guidelines suggest individualization of surgical management. However, these conditional recommendations are based on very low-certainty evidence due to limited data on surgical outcomes in this population. Objectives: To characterize procedural bleeding prophylaxis strategies and outcomes in children with mild type 1 VWD. Methods: This is a retrospective cohort study that included patients aged between 0 and 21 years with mild type 1 VWD (defined as von Willebrand factor antigen and/or an activity of 30-50 IU/dL) who underwent a procedure from July 1, 2017, to July 1, 2022. Demographic, surgical, medication, and bleeding data were collected by manual chart review. Results: A total of 161 procedures were performed in 108 patients. The population was primarily female (75%), White (77.8%), and non-Hispanic (79.6%). Median age was 15.8 years (IQR, 8.2-17.6). Fifty-nine surgeries were classified as major, 66 as minor, and 36 as dental. For most procedures, patients received only antifibrinolytics for bleeding prophylaxis (n = 128, 79.5%); desmopressin was used in 17 (10.6%) procedures, and von Willebrand factor concentrate was used in 12 (7.5%) procedures. Bleeding complications occurred in 8 (5.0%) procedures: these included 1 major, 4 clinically relevant nonmajor, and 3 minor bleeding events. No patient required blood transfusion or an additional procedure to achieve hemostasis. Most bleeding complications were seen following intrauterine device (IUD) placement (5/8). Nearly 30% of patients who underwent IUD placement reported bleeding. Conclusion: Pediatric patients with mild type 1 VWD can safely undergo procedures using a tailored approach. Bleeding complications were uncommon, with the majority following IUD placement.

The Effect of Topical Tranexamic Acid in Endoscopic Sinus Surgery: A Triple Blind Randomized Clinical Trial.

OBJECTIVE: Our aim is to evaluate the effect of topical tranexamic acid (TA) on bleeding and surgical quality field in the functional endoscopic sinus surgery (FESS). METHODS: A total of 74 patients who underwent FESS due to chronic rhinosinusitis were included. The patients were randomized into 2 groups. TA group (n = 37) received a topical cotton pledget soaked with TA and placebo (PL) group (n = 37) received a pledget soaked with saline solution. RESULTS: A significant effect was noted for the TA group versus the PL group in the grade 1 of the Boezaart scale at 35 minutes (4 for TA group and no case for PL group). This effect was absent for higher grades. We did not notice a significant effect between the 2 groups at 5 minutes. Blood loss was 359 ml in the TA group versus 441 ml in the PL group. No significant change was observed between the 2 groups concerning the blood parameters. No side effects were reported. CONCLUSION: Despite its safety when administrated locally and its low cost, TA provides limited effect on quality of surgical field after 35 minutes of the start of FESS in the patients with chronic rhinosinusitis. This effect was absent at the start of the intervention and when analyzing the blood loss and hematologic parameters.

Synthesis and Hemostatic Activity of New Amide Derivatives.

Eight dipeptides containing antifibrinolytic agents (tranexamic acid, aminocaproic acid, 4-(aminomethyl)benzoic acid, and glycine-natural amino acids) were synthesized in a three-step process with good or very good yields. DMT/NMM/TsO- (4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium toluene-4-sulfonate) was used as a coupling reagent. Hemolysis tests were used to study the effects of the dipeptides on blood components. Blood plasma clotting tests were used to examine their effects on thrombin time (TT), prothrombin time (PT), and the activated partial thromboplastin time (aPTT). The level of hemolysis did not exceed 1%. In clotting tests, TT, PT, and aPTT did not differentiate any of the compounds. The prothrombin times for all amides 1-8 were similar. The obtained results in the presence of amides 1-4 and 8 were slightly lower than for the other compounds and the positive control, and they were similar to the results obtained for TA. In the case of amide 3, a significantly decreased aPTT was observed. The aPTTs observed for plasma treated with amide 3 and TA were comparable. In the case of amide 6 and 8, TT values significantly lower than for the other compounds were found. The clot formation and fibrinolysis (CFF) assay was used to assess the influence of the dipeptides on the blood plasma coagulation cascade and the fibrinolytic efficiency of the blood plasma. In the clot formation and fibrinolysis assay, amides 5 and 7 were among the most active compounds. The cytotoxicity and genotoxicity of the synthesized dipeptides were evaluated on the monocyte/macrophage peripheral blood cell line. The dipeptides did not cause hemolysis at any concentrations. They exhibited no significant cytotoxic effect on SC cells and did not induce significant DNA damage.

Systematic review of hematuria and acute renal failure with tranexamic acid.

OBJECTIVES: To conduct a systematic review of tranexamic acid (TXA) and the risk of renal failure from urinary clots in adult patients with hematuria. METHODS: A systematic review of Medline, Embase, CENTRAL, www. CLINICALTRIALS: gov, and Google Scholar were searched. Randomized control trials (RCTs) and observational studies that assessed the risk of renal failure with use of TXA among adults with hematuria were included. The primary outcome was renal failure due to urinary tract clots with TXA compared to no TXA (or placebo) or comparator. RESULTS: We identified three RCTs (N = 466 patients) and three retrospective cohort studies (N=220 patients), and a total of 342 patients that had hematuria and received TXA. The patient population of the six studies included medical and surgical patients, with two of the three RCTs comprised patients undergoing percutaneous nephrolithotomy, and the third RCT comprised patients undergoing transurethral resection of the prostate. Documentation of renal function before and after TXA administration was documented in only two studies (N = 28 patients), and neither identified worsening renal function in those exposed to TXA. CONCLUSIONS: There are limited studies evaluating the risk of renal failure in patients with hematuria who were exposed to TXA, and the available data does not suggest an increased risk.

A Pharmacokinetic and Plasmin-Generation Pharmacodynamic Assessment of a Tranexamic Acid Regimen Designed for Cardiac Surgery With Cardiopulmonary Bypass.

OBJECTIVES: To examine the pharmacokinetics (PK) and pharmacodynamics of a tranexamic (TXA) regimen designed for cardiac surgery with cardiopulmonary bypass (CPB). DESIGN: A pilot study quantifying TXA concentrations, fibrinolysis markers, and a plasmin- generation (PG) assay. For comparison, PG assay was performed on pooled normal plasma (PNP) with varying TXA concentrations. SETTING: A single-center, tertiary, academic medical center. PARTICIPANTS: Twenty patients undergoing cardiac surgery with CPB for valve surgery and/or coronary artery bypass grafting. INTERVENTION: TXA 100 mg/h infusion for 5 hours starting before incision; 1 g TXA in CPB prime and 1 g TXA at CPB end prior to heparin reversal. MEASUREMENTS AND MAIN RESULTS: The PK fit a 2-compartment disposition model. TXA concentrations were above 15 mg/L in all patients during CPB through 2 hours post-TXA infusion. During and after CPB, the TXA regimen decreased the median peak PG by 60% (95% confidence interval [CI], 56%-62%). Lowest median peak PG occurred 15 minutes postprotamine. Peak median D-dimer level of 1.24 (0.95-1.71; 95% CI) mg/L occurred at 15 minutes postprotamine and baseline-adjusted ΔD dimer correlated with increased CPB time (p = 0.004) and lower TXA level (p = 0.001). The median 24-hour chest tube output was 447 (330-664; 95% CI) mL. PG assay on PNP revealed a plateau inhibition at 5 mM TXA (786 mg/L). CONCLUSIONS: This regimen, with total perioperative dose of 2.5 grams, provided TXA concentrations above 15 mg/L for all patients from CPB initiation through 2 hours post-TXA. PG was significantly inhibited (p < 0.0001) during and after CPB, with maximum inhibition measured at 15 minutes after protamine administration.

Pharmacokinetics of tranexamic acid after intravenous, intramuscular, and oral routes: a prospective, randomised, crossover trial in healthy volunteers.

BACKGROUND: In response to the World Health Organization call for research on alternative routes for tranexamic acid (TXA) administration in women with postpartum haemorrhage, we examined the pharmacokinetics of TXA after i.v., i.m., or oral administration. METHODS: We conducted a randomised, open-label, crossover trial in 15 healthy volunteers who received i.v. TXA 1 g, i.m. TXA 1 g, or oral TXA solution 2 g. Blood samples were drawn up to 24 h after administration. Tranexamic acid concentration was measured with liquid chromatography-mass spectrometry, and the parameters of the pharmacokinetic models were estimated using population pharmacokinetics. RESULTS: The median time to reach a concentration of 10 mg L-1 was 3.5 min for the i.m. route and 66 min for the oral route, although with the oral route the target concentration was reached in only 11 patients. Median peak concentrations were 57.5, 34.4, and 12.8 mg L-1 for i.v., i.m., and oral routes, respectively. A two-compartment open model with body weight as the main covariate best fitted the data. For a 70 kg volunteer, the population estimates were 10.1 L h-1 for elimination clearance, 15.6 L h-1 for intercompartmental clearance, 7.7 L for the volume of central compartment, and 10.8 L for the volume of the peripheral compartment. Intramuscular and oral bioavailabilities were 1.0 and 0.47, respectively, showing that i.m. absorption is fast and complete. Adverse events were mild and transient, mainly local reactions and low-intensity pain. CONCLUSIONS: The i.m. (but not oral) route appears to be an efficient alternative to i.v. tranexamic acid. Studies in pregnant women are needed to examine the impact of pregnancy on the pharmacokinetics. CLINICAL TRIAL REGISTRATION: EudraCT 2019-000285-38; NCT03777488.

Tranexamic acid to prevent operation in chronic subdural haematoma (TORCH): study protocol for a randomised placebo-controlled clinical trial.

BACKGROUND: Chronic subdural haematoma (cSDH) occurs mainly in the elderly. Surgical evacuation is effective, but in these old, often frail, patients with multi-comorbidity, surgery carries significant risks for future cognitive functioning and loss of independency. Therefore, a growing interest is noted for a non-surgical treatment with medication such as tranexamic acid (TXA). In five small retrospective series, this antifibrinolytic drug showed a beneficial effect on the spontaneous resolution of the haematoma, and with that, the necessity for surgery. METHODS: For this randomised, placebo-controlled clinical multicentre trial, all cSDH patients, over 50 years old with mild symptoms (Glasgow Coma Score (GCS) ≥ 14, modified National Institutes of Health Stroke Scale (mNIHSS) ≤ 4), a midline shift of ≤ 10 mm and in whom a primary conservative treatment is chosen, are eligible for study participation. After informed consent, 140 patients will be randomised to receive either TXA 500 mg or placebo two times daily for 28 days. The primary outcome is the necessity for surgery within 12 weeks; secondary outcomes are cSDH volume, neurological impairment (mNIHSS), falling incidents, cognitive functioning (Montreal Cognitive Assessment (MOCA)), performance in activities of daily living (Barthel and Lawton score), functional outcome (modified Rankin Scale (mRS)), quality of life (Short Form Health Survey (SF-36) and EuroQol 5-Dimension Health Survey (EQ-5D)), mortality and the use of care and health-related costs (Medical Consumption Questionnaire (iMCQ) and Productivity Cost Questionnaire (iPCQ)) at 12 weeks and 6 months. DISCUSSION: This phase III trial investigating the efficacy of TXA to prevent surgery for cSDH is the first in including patients using anticoagulants and mentally incompetent patients, since these comprise a significant part of the target population. Also, this study is one of the first to prospectively measure functional outcome and quality of life in cSDH patients. Final results of this study are expected in 2024. TRIAL REGISTRATION: Dutch Trial Registry (Nederlands Trial Register) NL6584 . Registered on 11 November 2017 ClinicalTrials.gov NCT03582293 . Registered on 11 July 2018 EU Clinical Trials Register 2017-004311-40 . Registered on 29 March 2018.

Effects of tranexamic acid on the amount of bleeding following vaginal delivery and its adverse effects: a double-blind placebo controlled randomized clinical trial.

INTRODUCTION: Postpartum hemorrhage (PPH) is the most important concern after delivery. Tranexamic acid (TXA), an anti-fibrinolytic agent, has been suggested for prevention and treatment of PPH. OBJECTIVE: The purpose of the present study was to find the effects of TXA on the amount of bleeding following vaginal delivery and its adverse effects. MATERIALS AND METHODS: The study was performed as a randomized double blind placebo controlled clinical trial on low risk pregnant women who delivered vaginally. The patients were randomly assigned into two groups. Women in the intervention group received 10 mg/kg infusion of TXA in 100 mL normal saline and the control group received one vial of distilled water (as placebo) in 100 mL normal saline. The primary outcome was amount of bleeding after delivery. The secondary outcomes were decreased in hemoglobin level, need for additional uterotonic agents and need for blood transfusion. All were evaluated 6 h after delivery and compared in the two groups. Participants were followed up to six weeks after delivery for any TXA side effects. RESULTS: Two hundred and seven women finished the study. There were no significant differences between the two groups in terms of demographic data and risk factors for bleeding. Mean blood loss and need to misoprostol was more in the control group (p=.033 and p=.000, respectively). Hemoglobin level was higher in the TXA group 6 h after delivery. None of the subjects needed blood transfusion, uterine balloon tamponade or emergency hysterectomy. Adverse effects were higher in the TXA group, however, there were no side effects between weeks 3 and 6 in both groups. There were no thromboembolic events during six weeks after delivery. CONCLUSIONS: Tranexamic acid can reduce the amount of bleeding after vaginal delivery in low risk women without having serious complications. Also, it may decrease the need for additional uterotonic agents. Trial registration number and registry website: IRCT20091023002624N22.

The effect of tranexamic acid on blood loss in orthognathic surgery: a randomized, placebo-controlled, equivalence study.

Orthognathic surgery can cause substantial bleeding. Recent meta-analyses concluded that there is a statistically significant reduction in perioperative blood loss with the preventive use of tranexamic acid (TA). However, the mean reported difference in bleeding was moderate, and the clinical relevance of this blood-sparing effect remains debated. We therefore conducted a prospective, double-blind, randomized, placebo-controlled equivalence study of the effect of TA in patients undergoing Lefort I or bimaxillary osteotomies. Our main outcome measure was total blood loss on postoperative day 1. The equivalence margin was ± 250 ml for the difference in blood loss and its 95% confidence interval. One hundred and forty-seven patients were randomized, of which 122 underwent bimaxillary osteotomies. Blood loss in the treatment group was 682 ± 323 vs. 875 ± 492 ml. The mean difference in bleeding was -132 [-243; -21] ml as per-protocol, but -193 [-329; -57] ml in intention-to-treat: the limits of this confidence interval exceeded the margin of equivalence. Similar results were obtained when analysing only patients undergoing bimaxillary osteotomy. Haemoglobin decreased by 1.8 ± 1.2 g/dl with TA, vs. 2.6 ± 1.1 g/dl with placebo (p<0.001). Our study did not demonstrate equivalence between TA and placebo on perioperative blood loss in orthognathic surgery. TA may reduce blood loss but without evidence of clinical consequences.

Efficacy and Safety of Tranexamic Acid for the Control of Surgical Bleeding in Patients Under Liposuction.

Liposuction remains one of the most frequently performed cosmetic surgical procedures and its popularity is increasing every year. However, since its inception, justified concerns regarding patient safety have placed limits on the volume of fat that can be aspirated, influenced by hemodynamic fluctuations and blood loss during liposuction. Tranexamic acid (TXA) is an antifibrinolytic agent that competitively inhibits the conversion of plasminogen to plasmin, thus preventing the binding and degradation of fibrin. Despite the existence of evidence of the effectiveness of TXA in orthopedic and cardiac surgeries, there is little evidence of its use in liposuction. The objective of this study was to evaluate the efficacy and safety of tranexamic acid in the control of surgical bleeding in patients undergoing liposuction, through a prospective, open, randomized and controlled clinical trial. Two groups of 25 participants each were formed to whom the application of TXA in a tumescent solution prior to liposuction or liposuction with the traditional technique was randomly assigned. The results showed a decrease in blood loss reflected by the differences in the final hematocrit values, as well as decrease in the same per aspirated volume (p = 0.003). No adverse events were found related with the TXA application and no blood transfusions were required in this group, in contrast to the control group where the need for blood transfusion was present in 20% of the intervened participants. LEVEL OF EVIDENCE II: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

COMPARISON OF HEMOSTASIS WITH TRANEXAMIC ACID IN TOTAL KNEE ARTHROPLASTY.

OBJECTIVE: To compare the use of intravenous and topical tranexamic acid (TXA) in unilateral primary total knee arthroplasty (TKA) in relation to blood loss and complications inherent to the medication. METHOD: Three groups with 14 patients each were constituted, and all of them were operated using the same surgical technique. In Group 1, usual measures for bleeding control were performed. Group 2 patients received TXA topically on the joint surface. In Group 3, intravenous TXA was used. Hemoglobin (HB), hematocrit (HTC), platelets (PLAT), prothrombin time, activated partial thromboplastin time and volume of blood drained observed 24 hours after arthroplasty were compared to the values of tests found before surgery. RESULTS: There was a decrease in the concentration of HB, HTC and PLAT in all groups in relation to the preoperative, however without significant difference. Group 3 had a lower mean volume of drained blood than the other groups, with statistical significance. No adverse effects or thromboembolic events were observed in the groups that received TXA. CONCLUSION: This study showed superiority in the use of intravenous TXA in decreasing the volume of bleeding, without increasing the risk of thromboembolic events. Level of Evidence I, High quality randomized trial with statistically significant difference or no statistically significant difference but narrow confidence intervals.

OBJETIVO: Comparar o uso do ácido tranexâmico (ATX) intravenoso e tópico em artroplastia total de joelho primária (ATJ) unilateral em relação à perda sanguínea e complicações inerentes à medicação. MÉTODOS: Três grupos com 14 pacientes cada foram divididos, todos operados utilizando-se a mesma técnica cirúrgica. No Grupo 1, medidas habituais para controle do sangramento foram realizadas. Pacientes do Grupo 2 receberam ATX topicamente na superfície articular. Já no Grupo 3, foi utilizado ATX intravenoso. Hemoglobina (HB), hematócrito (HTC), plaquetas (PLAQ), tempo de protrombina, tempo de tromboplastina parcialmente ativada e volume de sangue drenado observados 24 horas após a artroplastia foram comparados aos valores dos exames encontrados antes da cirurgia. RESULTADOS: Houve queda da concentração de HB, HTC e PLAQ em todos os grupos em relação ao pré-operatório, sem, contudo, diferença significante. O Grupo 3 apresentou menor volume médio de sangue drenado do que os demais grupos, com significância estatística. Não foram observados efeitos adversos ou eventos tromboembólicos nos grupos que receberam o ATX. CONCLUSÃO: O presente estudo demonstra superioridade da utilização de ATX intravenoso em diminuir o volume de sangramento, sem aumentar o risco de eventos tromboembólicos. Nível de Evidência I, Estudo clínico randomizado de alta qualidade com ou sem diferença estatisticamente significante, mas com intervalos de confiança estreitos.

Safety and efficacy of thromboelastography guidance of antifibrinolytic therapy in trauma patients: An observational cohort analysis.

BACKGROUND: Tranexamic acid (TXA) is an antifibrinolytic therapy intended to decrease blood loss and improve hemostasis in traumatic hemorrhage. Viscoelastic assays, such as thromboelastography (TEG), allow for the identification of a patient's specific hemostasis. The purpose of this research study was to explore the safety and efficacy of TEG-guided antifibrinolytic therapy in trauma patients. METHODS: This study was a retrospective review of trauma patients meeting institution-specific inclusion criteria for TXA. Patients were assigned to fibrinolytic groups per TEG LY30 data. Safety outcomes (24-h mortality, overall in-hospital mortality, and thromboembolic events) were compared between patients who did or did not receive TXA and within fibrinolytic groups. Mortality outcomes were adjusted for baseline Injury Severity Score (ISS). Secondary aims included blood product utilization, length of hospital, and intensive care unit stay. RESULTS: Hypofibrinolysis was the most common fibrinolytic phenotype. Adjusting for ISS, there were no significant differences in mortality. A 30.7% thromboembolism incidence was identified in the TXA group compared to 16.6% not receiving TXA (P = 0.26), with 72.7% of these patients experiencing fibrinolytic shutdown. CONCLUSIONS: There were no differences in 24-h mortality, all-cause mortality, or secondary outcomes. The difference in thromboembolic rates between patients receiving TXA and those who did not, while not statistically significant, poses clinical concern.

Comparison of hemostasis with tranexamic acid in total knee arthroplasty / Comparação da hemostasia com ácido tranexâmico em artroplastia total de joelho

ABSTRACT Objective: To compare the use of intravenous and topical tranexamic acid (TXA) in unilateral primary total knee arthroplasty (TKA) in relation to blood loss and complications inherent to the medication. Method: Three groups with 14 patients each were constituted, and all of them were operated using the same surgical technique. In Group 1, usual measures for bleeding control were performed. Group 2 patients received TXA topically on the joint surface. In Group 3, intravenous TXA was used. Hemoglobin (HB), hematocrit (HTC), platelets (PLAT), prothrombin time, activated partial thromboplastin time and volume of blood drained observed 24 hours after arthroplasty were compared to the values of tests found before surgery. Results: There was a decrease in the concentration of HB, HTC and PLAT in all groups in relation to the preoperative, however without significant difference. Group 3 had a lower mean volume of drained blood than the other groups, with statistical significance. No adverse effects or thromboembolic events were observed in the groups that received TXA. Conclusion: This study showed superiority in the use of intravenous TXA in decreasing the volume of bleeding, without increasing the risk of thromboembolic events. Level of Evidence I, High quality randomized trial with statistically significant difference or no statistically significant difference but narrow confidence intervals.

RESUMO Objetivo: Comparar o uso do ácido tranexâmico (ATX) intravenoso e tópico em artroplastia total de joelho primária (ATJ) unilateral em relação à perda sanguínea e complicações inerentes à medicação. Métodos: Três grupos com 14 pacientes cada foram divididos, todos operados utilizando-se a mesma técnica cirúrgica. No Grupo 1, medidas habituais para controle do sangramento foram realizadas. Pacientes do Grupo 2 receberam ATX topicamente na superfície articular. Já no Grupo 3, foi utilizado ATX intravenoso. Hemoglobina (HB), hematócrito (HTC), plaquetas (PLAQ), tempo de protrombina, tempo de tromboplastina parcialmente ativada e volume de sangue drenado observados 24 horas após a artroplastia foram comparados aos valores dos exames encontrados antes da cirurgia. Resultados: Houve queda da concentração de HB, HTC e PLAQ em todos os grupos em relação ao pré-operatório, sem, contudo, diferença significante. O Grupo 3 apresentou menor volume médio de sangue drenado do que os demais grupos, com significância estatística. Não foram observados efeitos adversos ou eventos tromboembólicos nos grupos que receberam o ATX. Conclusão: O presente estudo demonstra superioridade da utilização de ATX intravenoso em diminuir o volume de sangramento, sem aumentar o risco de eventos tromboembólicos. Nível de Evidência I, Estudo clínico randomizado de alta qualidade com ou sem diferença estatisticamente significante, mas com intervalos de confiança estreitos.

Tranexamic acid evidence and controversies: An illustrated review.

Tranexamic acid (TXA) is an antifibrinolytic agent commonly used for the treatment or prevention of bleeding. Indications for TXA are diverse, including heavy menstrual bleeding, trauma, postpartum hemorrhage, traumatic brain injury, and surgical site bleeding. Despite decades of use and a robust body of evidence, hesitancy using TXA persists in many clinical settings. This illustrated review describes the history, pharmacology, and practical considerations of TXA use. We also describe the major landmark randomized controlled trials of TXA and their implications. Finally, we review the evidence around common controversies surrounding TXA such as the risk of thrombosis, prescription along with combined hormonal contraceptives, and use in patients with gross hematuria.

Treatment of bleeding in patients with liver disease.

Patients with cirrhosis frequently have complex alterations in their hemostatic system. Although routine diagnostic tests of hemostasis in cirrhosis (platelet count, prothrombin time, fibrinogen level) are suggestive of a bleeding tendency, it is now widely accepted that these tests do not reflect hemostatic competence in this population. Rather, patients with cirrhosis appear to have a rebalanced hemostatic system with hypercoagulable elements. Therefore, routine correction of hemostasis laboratory values, for example by fresh frozen plasma or platelet concentrates, with the aim to avoid spontaneous or procedure-related bleeding is not indicated as is outlined in recent clinical guidance documents. However, little guidance on how to manage patients with cirrhosis that are actively bleeding is available. Here we present three common bleeding scenarios, variceal bleeding, post-procedural bleeding and bleeding in a critically ill cirrhosis patient, with specific management suggestions. As patients with cirrhosis generally have adequate hemostatic competence and as bleeding complications may be unrelated to hemostatic failure, prohemostatic therapy is not the first line of management in bleeding patients with cirrhosis, even in the presence of markedly abnormal platelet counts and/or prothrombin times. We provide a rationale for the restrictive approach to prohemostatic therapy in bleeding patients with cirrhosis.

ε-Aminocaproic acid versus tranexamic acid in children undergoing complex cranial vault reconstruction for repair of craniosynostosis.

Complex cranial vault reconstruction (CCVR) for pediatric craniosynostosis is a high blood loss surgery, for which antifibrinolytic agents have been shown to reduce bleeding and transfusion requirements. The relative efficacy of ε-aminocaproic acid (EACA) versus tranexamic acid (TXA) has not yet been evaluated in this population. The aim of this retrospective study was to compare perioperative blood loss and transfusion in CCVR patients receiving EACA versus TXA. In a CCVR cohort of 95 children, 47 received EACA and 48 received TXA. We found no differences in demographics, adverse outcomes, calculated blood loss (CBL), or transfusion requirements between the two antifibrinolytic groups.

Tranexamic acid to reduce head injury death in people with traumatic brain injury: the CRASH-3 international RCT.

BACKGROUND: Tranexamic acid safely reduces mortality in traumatic extracranial bleeding. Intracranial bleeding is common after traumatic brain injury and can cause brain herniation and death. We assessed the effects of tranexamic acid in traumatic brain injury patients. OBJECTIVE: To assess the effects of tranexamic acid on death, disability and vascular occlusive events in traumatic brain injury patients. We also assessed cost-effectiveness. DESIGN: Randomised trial and economic evaluation. Patients were assigned by selecting a numbered treatment pack from a box containing eight packs that were identical apart from the pack number. Patients, caregivers and those assessing outcomes were masked to allocation. All analyses were by intention to treat. We assessed the cost-effectiveness of tranexamic acid versus no treatment from a UK NHS perspective using the trial results and a Markov model. SETTING: 175 hospitals in 29 countries. PARTICIPANTS: Adults with traumatic brain injury within 3 hours of injury with a Glasgow Coma Scale score of ≤ 12 or any intracranial bleeding on computerised tomography scan, and no major extracranial bleeding, were eligible. INTERVENTION: Tranexamic acid (loading dose 1 g over 10 minutes then infusion of 1 g over 8 hours) or matching placebo. MAIN OUTCOME MEASURES: Head injury death in hospital within 28 days of injury in patients treated within 3 hours of injury. Secondary outcomes were early head injury deaths, all-cause and cause-specific mortality, disability, vascular occlusive events, seizures, complications and adverse events. RESULTS: Among patients treated within 3 hours of injury (n = 9127), the risk of head injury death was 18.5% in the tranexamic acid group versus 19.8% in the placebo group (855/4613 vs. 892/4514; risk ratio 0.94, 95% confidence interval 0.86 to 1.02). In a prespecified analysis excluding patients with a Glasgow Coma Scale score of 3 or bilateral unreactive pupils at baseline, the results were 12.5% in the tranexamic acid group versus 14.0% in the placebo group (485/3880 vs. 525/3757; risk ratio 0.89, 95% confidence interval 0.80 to 1.00). There was a reduction in the risk of head injury death with tranexamic acid in those with mild to moderate head injury (166/2846 vs. 207/2769; risk ratio 0.78, 95% confidence interval 0.64 to 0.95), but in those with severe head injury (689/1739 vs. 685/1710; risk ratio 0.99, 95% confidence interval 0.91 to 1.07) there was no apparent reduction (p-value for heterogeneity = 0.030). Early treatment was more effective in mild and moderate head injury (p = 0.005), but there was no obvious impact of time to treatment in cases of severe head injury (p = 0.73). The risk of disability, vascular occlusive events and seizures was similar in both groups. Tranexamic acid is highly cost-effective for mild and moderate traumatic brain injury (base case of £4288 per quality-adjusted life-year gained). CONCLUSION: Early tranexamic acid treatment reduces head injury deaths. Treatment is cost-effective for patients with mild or moderate traumatic brain injury, or those with both pupils reactive. FUTURE WORK: Further trials should examine early tranexamic acid treatment in mild head injury. Research on alternative routes of administration is needed. LIMITATIONS: Time to treatment may have been underestimated. TRIAL REGISTRATION: Current Controlled Trials ISRCTN15088122, ClinicalTrials.gov NCT01402882, EudraCT 2011-003669-14, Pan African Clinical Trial Registry PACTR20121000441277. FUNDING: The project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 26. See the NIHR Journals Library website for further project information. In addition, funding was provided by JP Moulton Charitable Trust, Joint Global Health Trials (Medical Research Council, Department for International Development and the Wellcome Trust). This project was funded by the NIHR Global Health Trials programme.

Traumatic brain injury is a leading cause of death and disability worldwide, with over 60 million new cases each year. When the head is injured there is often bleeding inside the brain, which can continue for some time and worsen after hospital admission. This bleeding increases pressure inside the skull, causing further damage to the brain, which can be fatal or result in serious disability. Tranexamic acid is a cheap drug that reduces bleeding in other conditions. A large trial of accident victims (other than those with head injury) found that it reduced the chances of bleeding to death. We wanted to find out if tranexamic acid would also reduce deaths among patients with head injuries. We studied just under 13,000 patients with traumatic brain injury who did not have other major injuries to their bodies from 175 hospitals across 29 countries. Patients were assigned at random to receive either tranexamic acid or a dummy medicine called a placebo. Neither the clinical team nor the patient knew which medicine the patient received. All patients received the usual treatments given to head-injured patients. Outcomes from 9127 participants were analysed. Among patients treated early, within 3 hours, the rate of head injury death was 18.5% (855/4613) in the tranexamic acid group and 19.8% (892/4514) in the placebo group. We found no evidence of an effect of tranexamic acid overall. However, in patients with mild or moderate traumatic brain injury, there was a 20% reduction in deaths. There were no side effects and no increase in disability in survivors when the drug was used. The economic analysis shows that tranexamic acid represents value for money for patients with mild or moderate traumatic brain injury.

Effect of tranexamic acid on markers of inflammation in children undergoing craniofacial surgery.

BACKGROUND: Tranexamic acid (TXA) reduces blood loss and transfusion requirements during craniosynostosis surgery in small children. Possible interaction from TXA on the inflammatory system is unknown. OBJECTIVE: To evaluate the effect of TXA on a wide range of inflammatory markers in children receiving TXA in a randomized, blinded, and placebo controlled study design. METHODS: Thirty children undergoing craniosynostosis surgery with significant blood loss received TXA (bolus dose of 10 mg kg-1 followed by 8 hours continuous infusion of 3 mg kg-1  h-1 ) or placebo in a randomized, double-blinded study design. Using a new proximity extension assays employing a panel of inflammatory biomarkers samples was used for analysis of blood samples obtained pre-operatively, 4 and 24 hours after operation. RESULTS: Ninety-two inflammatory parameters were measured. TXA did not affect any of the measured parameters as compared with placebo. Among 34 of the 92 pro- and antiinflammatory parameters investigated changes were observed between pre-operative, 4 or 24 hours, respectively, reflecting immune activation during surgical stress. CONCLUSION: TXA administration in a low-dose regimen including bolus followed by 8 hours infusion during craniosynostosis surgery did not change any of 92 inflammatory markers as compared with placebo.