Physiologically based modelling of tranexamic acid pharmacokinetics following intravenous, intramuscular, sub-cutaneous and oral administration in healthy volunteers

THE ROLE OF TRANEXAMIC ACID IN POSTPARTUM HEMORRHAGE: A NARRATIVE REVIEW

ABSTRACT

Postpartum hemorrhage is the leading cause of preventable maternal illness and death globally and carries a disproportionately high burden of mortality in low- to middle-income countries. Tranexamic acid, an antifibrinolytic drug, has been widely adopted to control bleeding in trauma and other surgical conditions. Within the last decade, the World Health Organization updated their guidelines for the treatment of postpartum hemorrhage to include the use of tranexamic acid in all cases of postpartum hemorrhage. However, despite these guidelines and the proven utility of tranexamic acid to treat postpartum hemorrhage, widespread adoption of tranexamic acid into global standards of care across professional organizations has not been achieved. It is important for healthcare providers to understand the etiologies of postpartum hemorrhage, the mechanism of action and adverse effect profile of tranexamic acid, and the available literature regarding the use of tranexamic acid to prevent and treat postpartum hemorrhage to provide the best care for the pregnant patient.

Tranexamic Acid Use in the Surgical Arena: A Narrative Review

INTRODUCTION

Tranexamic acid (TXA) is a potent antifibrinolytic drug that inhibits the activation of plasmin by plasminogen. While not a new medication, TXA has quickly gained traction across a variety of surgical subspecialties to prevent and treat bleeding. Knowledge on the use of this drug is essential for the modern surgeon to continue to provide excellent care to their patients.

METHODS

A comprehensive review of the PubMed database was conducted of articles published within the last 10 y (2014-2024) relating to TXA and its use in various surgical subspecialties. Seminal studies regarding the use of TXA older than 10 y were included from the author's archives.

RESULTS

Indications for TXA are not limited to trauma alone, and TXA is utilized across a variety of surgical subspecialties from neurosurgery to hepatic surgery to control hemorrhage. Overall, TXA is well tolerated with common dose-dependent adverse effects, including headache, nasal symptoms, dizziness, nausea, diarrhea, and fatigue. More severe adverse events are rare and easily mitigated by not exceeding a dose of 50 mg/kg.

CONCLUSIONS

The administration of TXA as an adjunct to treat trauma saves lives. The ability of TXA to induce seizures is dose dependent with identifiable risk factors, making this serious adverse effect predictable. As for the potential for TXA to cause thrombotic events, uncertainty remains. If this association is proven to be real, the risk will likely be small, since the use of TXA is still advantageous in most situations because of its efficacy for a more common concern, bleeding.

Evaluation of the use of tranexamic acid in the postoperative period in patients with scoliosis undergoing posterior fusion

Scoliosis is the most prevalent type of spinal deformity, with a 2-3% prevalence in the general population. Moreover, surgery for scoliotic deformity may result in severe blood loss and, consequently, the need for blood transfusions, thereby increasing surgical morbidity and the rate of complications. Several antifibrinolytic drugs, such as tranexamic acid, have been regarded as safe and effective options for reducing blood loss. Therefore, the present study aimed to analyse the effectiveness of this drug for controlling bleeding when used intraoperatively and in the first 48 h after surgery. A prospective randomized study of a cohort of patients included in a mass event for scoliosis treatment using PSF was performed. Twenty-eight patients were analysed and divided into two groups: 14 patients were selected for intraoperative and postoperative use of tranexamic acid (TXA), and the other 14 were selected only during the intraoperative period. The drainage bleeding rate, length of hospital stay, number of transfused blood units, and rate of adverse clinical effects were compared. All the patients involved had similar numbers of fusion levels addressed and similar scoliosis profiles. The postoperative bleeding rate through the drain did not significantly differ between the two groups (p > 0.05). There was no significant difference in the number of transfused blood units between the groups (p = 0.473); however, in absolute numbers, patients in the control group received more transfusions. The length of hospital stay was fairly similar between the groups, with no statistically significant difference. Furthermore, the groups had similar adverse effects (p = 0.440), with the exception of nausea and vomiting, which were twice as common in the TXA group postoperatively than in the control group. No significant differences were found in the use of TXA during the first 48 postoperative hours or in postoperative outcomes.

The Effect of Intravenous Tranexamic Acid on Postoperative Ecchymoses after Upper Blepharoplasty

Background

Tranexamic acid has been increasingly used in facial plastic surgery to improve perioperative hemostasis. While subcutaneous tranexamic acid has been found to not significantly decrease postoperative ecchymoses following upper blepharoplasty, systemic administration has not previously been studied.

Methods

A total of 325 patients undergoing upper blepharoplasty were randomly assigned to either receive intravenous tranexamic acid or serve as a control. Patients in the experimental group were administered 1 g of tranexamic acid intravenously 10 minutes before surgical incision. A similar upper blepharoplasty technique was performed by two American Society of Ophthalmic Plastic and Reconstructive Surgery-trained surgeons. Follow-up was conducted at a median of 8 days postsurgery. Patient photographs were evaluated by two independent graders to rate ecchymoses on a scale of 0 (least) to 10 (most).

Results

Of the 325 included patients, 138 patients received intravenous tranexamic acid and 187 patients did not. The average ecchymosis rating for the control group at day 8 was 5.8 ± 1.7, while the average rating for the tranexamic acid group at the same time point was 4.1 ± 1.6 (P < 0.0001). There was a trend toward decreased ecchymoses in the tranexamic acid group at earlier and later postoperative timepoints that did not reach statistical significance. No hemorrhagic or systemic embolic complications occurred.

Conclusions

Systemic tranexamic acid may reduce postoperative ecchymoses after upper blepharoplasty surgery, reaching significance at the eighth postoperative day, which may lead to improved patient satisfaction and decreased occupational downtime.

An investigation into the effects of ink formulations of semi-solid extrusion 3D printing on the performance of printed solid dosage forms

Semi-solid extrusion (SSE) 3D printing has recently attracted increased attention for its pharmaceutical application as a potential method for small-batch manufacturing of personalised solid dosage forms. It has the advantage of allowing ambient temperature printing, which is especially beneficial for the 3D printing of thermosensitive drugs. In this study, the effects of polymeric compositions (single hydroxypropyl methylcellulose (HPMC) system and binary HPMC + polyvinylpyrrolidone (PVP) system), disintegrant (silicon oxide (SiO2)), and active pharmaceutical ingredients (tranexamic acid (TXA) and paracetamol (PAC)) on the printability of semisolid inks and the qualities of SSE printed drug-loaded tablets were investigated. Printability is defined by the suitability of the material for the process in terms of its physical properties during extrusions and post-extrusion, including rheology, solidification time, avoiding slumping, etc. The rheological properties of the inks were investigated as a function of polymeric compositions and drug concentrations and further correlated with the printability of the inks. The SSE 3D printed tablets were subjected to a series of physicochemical properties characterisations and in vitro drug release performance evaluations. The results indicated that an addition of SiO2 would improve 3D printing shape fidelity (e.g., pore area and porosity) by altering the ink rheology. The pores of HPMC + PVP + 5PAC prints completely disappeared after 12 hours of drying (pore area = 0 mm2). An addition of SiO2 significantly improved the pore area of the prints which are 3.5 ± 0.1 mm2. It was noted that the drug release profile of PAC significantly increased (p < 0.05) when additive SiO2 was incorporated in the formulation. This could be due to a significantly higher porosity of HPMC + PVP + SiO2 + PAC (70.3 ± 0.2%) compared to HPMC + PVP + PAC (47.6 ± 2.1%). It was also likely that SiO2 acted as a disintegrant speeding up the drug release process. Besides, the incorporation of APIs with different aqueous solubilities, as well as levels of interaction with the polymeric system showed significant impacts on the structural fidelity and subsequently the drug release performance of 3D printed tablets.

Tranexamic acid by the intramuscular or intravenous route for the prevention of postpartum haemorrhage in women at increased risk: a randomised placebo-controlled trial (I'M WOMAN)

BACKGROUND

Postpartum haemorrhage (PPH) causes about 70,000 maternal deaths every year. Tranexamic acid (TXA) is a life-saving treatment for women with PPH. Intravenous (IV) TXA reduces deaths due to PPH by one-third when given within 3 h of childbirth. Because TXA is more effective when given early and PPH usually occurs soon after childbirth, giving TXA just before childbirth might prevent PPH. Although several randomised trials have examined TXA for PPH prevention, the results are inconclusive. Because PPH only affects a small proportion of births, we need good evidence on the balance of benefits and harms before using TXA to prevent PPH. TXA is usually given by slow IV injection. However, recent research shows that TXA is well tolerated and rapidly absorbed after intramuscular (IM) injection, achieving therapeutic blood levels within minutes of injection.

METHODS

The I'M WOMAN trial is an international, multicentre, three-arm, randomised, double-blind, placebo-controlled trial to assess the effects of IM and IV TXA for the prevention of PPH in women with one or more risk factors for PPH giving birth vaginally or by caesarean section.

DISCUSSION

The trial will provide evidence of the benefits and harms of TXA for PPH prevention and the effects of the IM and IV routes of administration. The IM route should be as effective as the IV route for preventing bleeding. There may be fewer side effects with IM TXA because peak blood concentrations are lower than with the IV route. IM TXA also has practical advantages as it is quicker and simpler to administer. By avoiding the need for IV line insertion and a slow IV injection, IM administration would free up overstretched midwives and doctors to focus on looking after the mother and baby and expand access to timely TXA treatment.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05562609. Registered on 3 October 2022. ISRCTN Registry ISRCTN12590098. Registered on 20 January 2023. Pan African Clinical Trial Registry PACTR202305473136570. Registered on 18 May 2023.

[Efficacy and safety of multiple-dose intravenous tranexamic acid for reducing blood loss in complex tibial plateau fractures: A prospective randomized controlled trial]

Objective

To investigate the efficacy and safety of multiple-dose intravenous tranexamic acid (TXA) for reducing blood loss in complex tibial plateau fractures with open reduction internal fixation by a prospective randomized controlled trial.

Methods

A study was conducted on patients with Schatzker type Ⅳ-Ⅵ tibial plateau fractures admitted between August 2020 and December 2022. Among them, 88 patients met the selection criteria and were included in the study. They were randomly allocated into 3 groups, the control group (28 cases), single-dose TXA group (31 cases), and multiple-dose TXA group (29 cases), using a random number table method. There was no significant difference ( P>0.05) in terms of age, gender, body mass index, the Schatzker type and side of fracture, laboratory examinations [hemoglobin (Hb), activated partial thromboplastin time (APTT), prothrombin time (PT), fibrinogen (Fib), international normalized ratio (INR), D-dimer, and interleukin 6 (IL-6)], and preoperative blood volume. The control group received intravenous infusion of 100 mL saline at 15 minutes before operation and 3, 6, and 24 hours after the first administration. The single-dose TXA group received intravenous infusion of 1 g TXA (dissolved in 100 mL saline) at 15 minutes before operation, followed by an equal amount of saline at each time point after the first administration. The multiple-dose TXA group received intravenous infusion of 1 g TXA (dissolved in 100 mL saline) at each time point. The relevant indicators were recorded and compared between groups to evaluate the effectiveness and safety of TXA, including hospital stays, operation time, occurrence of infection; the occurrence of lower extremity deep vein thrombosis, intermuscular vein thrombosis, and pulmonary embolism at 1 week after operation; the lowest postoperative Hb value and Hb reduction rate, the difference (change value) between pre- and post-operative APTT, PT, Fib, and INR; D-dimer and IL-6 at 24 and 72 hours after operation; total blood loss, intraoperative blood loss, hidden blood loss, drainage flow during 48 hours after operation, and postoperative blood transfusion.

Results

① TXA efficacy evaluation: the lowest Hb value in the control group was significantly lower than that in the other two groups ( P<0.05), and there was no significant difference between the single- and multiple-dose TXA groups ( P>0.05). The Hb reduction rate, total blood loss, intraoperative blood loss, drainage flow during 48 hours after operation, and hidden blood loss showed a gradual decrease trend in the control group, single-dose TXA group, and multiple-dose TXA group. And differences were significant ( P<0.05) in the Hb reduction rate and drainage flow during 48 hours after operation between groups, and the total blood loss and hidden blood loss between control group and other two groups. ② TXA safety evaluation: no lower extremity deep vein thrombosis or pulmonary embolism occurred in the three groups after operation, but 3, 4, and 2 cases of intermuscular vein thrombosis occurred in the control group, single-dose TXA group, and multiple-dose TXA group, respectively, and the differences in the incidences between groups were not significant ( P>0.05). There was no significant difference in the operation time between groups ( P>0.05). But the length of hospital stay was significantly longer in the control group than in the other groups ( P<0.05); there was no significant difference between the single- and multiple-dose TXA groups ( P>0.05). ③ Effect of TXA on blood coagulation and inflammatory response: the incisions of the 3 groups healed by first intention, and no infections occurred. The differences in the changes of APTT, PT, Fib, and INR between groups were not significant ( P>0.05). The D-dimer and IL-6 in the three groups showed a trend of first increasing and then decreasing over time, and there was a significant difference between different time points in the three groups ( P<0.05). At 24 and 72 hours after operation, there was no significant difference in D-dimer between groups ( P>0.05), while there was a significant difference in IL-6 between groups ( P<0.05).

Conclusion

Multiple intravenous applications of TXA can reduce perioperative blood loss and shorten hospital stays in patients undergoing open reduction and internal fixation of complex tibial plateau fractures, provide additional fibrinolysis control and ameliorate postoperative inflammatory response.

Alternative routes for tranexamic acid treatment in obstetric bleeding (WOMAN-PharmacoTXA trial): a randomised trial and pharmacological study in caesarean section births

OBJECTIVE

To examine the safety, efficacy and pharmacology of intravenous (IV), intramuscular (IM) and oral tranexamic acid (TXA) use in pregnant women.

DESIGN

Randomised, open-label trial.

SETTING

Hospitals in Pakistan and Zambia.

POPULATION

Women giving birth by caesarean section.

METHODS

Women were randomised to receive 1 g IV, 1 g IM, 4 g oral TXA or no TXA. Adverse events in women and neonates were recorded. TXA concentration in whole blood was measured and the concentrations over time were examined with population pharmacokinetics. The relationship between drug exposure and D-dimer was explored. The trial registration is NCT04274335.

MAIN OUTCOME MEASURES

Concentration of TXA in maternal blood.

RESULTS

Of the 120 women included in the randomised safety study, there were no serious maternal or neonatal adverse events. TXA concentrations in 755 maternal blood and 87 cord blood samples were described by a two-compartment model with one effect compartment linked by rate transfer constants. Maximum maternal concentrations were 46.9, 21.6 and 18.1 mg/L for IV, IM and oral administration, respectively, and 9.5, 7.9 and 9.1 mg/L in the neonates. The TXA response was modelled as an inhibitory effect on the D-dimer production rate. The half-maximal inhibitory concentration (IC50 ) was 7.5 mg/L and was achieved after 2.6, 6.4 and 47 minutes with IV, IM and oral administration of TXA, respectively.

CONCLUSIONS

Both IM and oral TXA are well tolerated. Oral TXA took about 1 hour to reach minimum therapeutic concentrations and would not be suitable for emergency treatment. Intramuscular TXA inhibits fibrinolysis within 10 minutes and may be a suitable alternative to IV.

The role of tranexamic acid in the management of postpartum haemorrhage

In the last decades, tranexamic acid (TXA) has emerged as an essential tool in blood loss management in obstetrics. TXA prophylaxis for postpartum haemorrhage (PPH) has been studied in double-blind, placebo-controlled, randomized clinical trials (RCTs). Given the small observed preventive effect, the systematic use of TXA for vaginal and/or caesarean deliveries remains controversial. The result of a pharmacokinetic modelling suggests that relative to intravenous administration, intramuscular administration may be an equally effective alternative route for preventing PPH and may enable access to this drug in low-resource countries. Prophylaxis is currently studied in high-risk populations, such as women with prepartum anaemia or placenta previa. TXA effectively reduces blood loss and PPH-related morbidity and mortality during active PPH, as demonstrated by high-grade evidence from large RCTs. The drug has a good safety profile: in most cases, only mild gastrointestinal or visual adverse events may be observed. TXA use does not increase the risk of serious adverse events, such as venous or arterial thromboembolism, seizures, or acute kidney injury. The TRACES in vivo analysis of biomarkers of TXA's antifibrinolytic effect have suggested that a dose of at least 1 g is required for the treatment of PPH. The TRACES pharmacokinetic model suggests that because TXA can be lost in the haemorrhaged blood, a second dose should be administered if the PPH continues or if severe coagulopathy occurs. Future pharmacodynamic analyses will focus on the appropriateness of TXA dosing regimens with regard to the intensity of fibrinolysis in catastrophic obstetric events.

Tranexamic acid administration practice in otolaryngology head & neck surgery; international survey

PURPOSE

Tranexamic acid (TXA) is a potent pro-coagulation drug. Pre-operative, preventive TXA administration and TXA use for active bleeding are established treatments in many medical situations; yet, less is known about its use in otolaryngology head and neck surgery practice. The primary study goals were: MATERIALS AND METHODS: This is an international survey exploring TXA administration strategy. The electronic, anonymous, questionnaire was emailed to all registered Israeli and American Otolaryngology Head and Neck Surgery (OHNS) physicians, investigating TXA administration: RESULTS: Overall, 317 otolaryngologists participated in the study. TXA was administered to 40.5 % of the pediatric population and 50 % of the adult patients when needed. Epistaxis was the most common indication for TXA administration (48-55 %). A small number of otolaryngologists, 4-13 %, recommended preventive TXA for various operations. More surgeons include TXA in their practice and adjusted the dose according to renal function in academic compared to non-academic medical centers and among otolaryngologists practicing in Israel compared to the United States.

CONCLUSIONS

TXA is provided by many otolaryngologists to treat active epistaxis but to a substantially lesser extent as a preventive measure. TXA is given to children and adults, some with substantial comorbidities. Treatment is more common among surgeons working in academic institutes and medical centers in Israel.

Alternative routes to intravenous tranexamic acid for postpartum hemorrhage: A systematic search and narrative review

OBJECTIVE

To review available data on tranexamic acid (TXA) plasma concentration needed to inhibit fibrinolysis and the time to achieve this concentration when giving TXA by different routes in humans. To identify ongoing trials assessing alternatives to intravenous TXA administration.

METHODS

We updated two previous systematic reviews by searching MEDLINE, EMBASE, OviSP, and ISI Web of Science from database inception to July 2021. We also searched the WHO International Clinical Trials Registry Platform for ongoing trials to July 2021. Titles and abstracts were screened for relevant trials. Two reviewers independently reviewed and agreed the trials to be included.

RESULTS

Plasma TXA concentrations over 10 mg/L provide near maximal inhibition of fibrinolysis, with concentrations over 5 mg/L providing partial inhibition. Oral TXA tablets take about 1 h to reach a plasma concentration of 5 mg/L in postpartum women. Studies in healthy volunteers and shocked trauma patients show that intramuscular TXA achieves a plasma level of over 10 mg/L within 15 min. One trial is ongoing to determine the pharmacokinetics of intramuscular and oral solution TXA in pregnant women.

CONCLUSION

Intramuscular TXA in healthy volunteers and shocked trauma patients reaches therapeutic concentration rapidly. Oral TXA tablets take too long to reach the minimum therapeutic concentration in postpartum women.

Advances in hemorrhage control resuscitation

PURPOSE OF REVIEW

Despite significant advances in trauma management over the last twenty years, uncontrolled hemorrhage remains the leading cause of preventable death in trauma. We review recent changes affecting hemorrhage control resuscitation.

RECENT FINDINGS

Early blood product usage has become well established as a standard of care in trauma hemorrhage control. To enable this, low titer group A liquid plasma and group O whole blood are increasingly utilized. Single donor apheresis platelets have now replaced pooled donor platelets in the USA and are often pathogen reduced, which has implications for trauma resuscitation. Further work is examining timing and dosing of tranexamic acid and the debate in factor concentrate usage in trauma induced coagulopathy continues to evolve. The 'Stop the bleed' campaign has highlighted how important the use of hemostatic dressings are in hemorrhage control, as too is the expanded use of endovascular aortic occlusion. We highlight the ongoing research into desmopressin use and the undetermined significance of ionized calcium levels in trauma. Finally, we discuss our own hospital experience with coagulation testing and the paucity of evidence of improved outcomes with viscoelastic testing.

SUMMARY

Improving trauma coagulopathy diagnostics and hemorrhage control are vital if we are to decrease the mortality associated with trauma.

Editorial Commentary: The Current Evidence in Support of Tranexamic Acid in Arthroscopic Surgery Is Poor

Tranexamic acid (TXA) has been used to treat severe bleeding events for nearly 60 years and is on the list of World Health Organization essential medicines. Initially, it was described to treat heavy menstrual bleeding, but it is now used for a variety of applications. In orthopedic surgery, TXA is commonly used to reduce bleeding after total joint arthroplasty and spine surgery. The use of TXA for joint arthroplasty has been principally endorsed by various orthopedic societies, but they have also criticized a lack of evidence for high-risk patients with a history of pulmonary embolus, vascular stents, stroke, transient ischemic attack, and other cardiac, respiratory, or vascular conditions. TXA may also reduce bleeding complications in arthroscopic surgery, and the findings of recent meta-analyses suggest that intravenous application reduced drainage output and the need for knee joint aspiration and reduced knee swelling. It also had a positive short-term effect on clinical and functional outcomes. However, high risk of bias, low-study quality, and heterogeneity substantially reduced the quality of evidence and the validity of the study conclusions. In my opinion, on the basis of the current evidence, the routine use of TXA in arthroscopic surgery is not recommended.

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.

Dose tranexamic acid reduce blood loss associated with simultaneous bilateral distal tibial tubercle-high tibial osteotomy?

Background

Simultaneous bilateral distal tibial tubercle high tibial osteotomy (SBDTT-HTO) can result in increased blood loss. The aim of this study is to evaluate the actual hemostatic effect of different tranexamic acid (TXA) treatment regimen in SBDTT-HTO.

Methods

We conducted a retrospective case–control study including 54 patients who underwent SBDTT-HTO. The single-dose group (n = 18) received 1 g of intravenous TXA 15–30 min before surgery, the two-dose group (n = 18) received an additional 1 g of intravenous TXA 6 h after surgery, and the multiple-dose group (n = 18) received an additional 1 g intravenous TXA per-day until discharge. Blood loss, hemoglobin levels, occurrence of any adverse events,functional analysis, quality of life, and pain assessmentswere compared among the three groups.

Results

The total blood loss, hidden blood loss, drainage volumes, and haemoglobin level in the multiple-dose group all occupy a significant advantage.(p < 0.05). In addition, better quality of life were observed in patients belonging to the multiple-dose group then single-dose group.(p < 0.05).

Conclusions

Based on our results, for patients undergoing SBDTT-HTO, sequential intravenous TXA administration can effectively and safely reduce blood loss,maintain postoperative Hb levels,and with the advantage of accelerating recovery.