The design of a Bayesian adaptive clinical trial of tranexamic acid in severely injured children

Tranexamic Acid in Pediatric Traumatic Brain Injury: A Multicenter Retrospective Observational Study

STUDY OBJECTIVE

Tranexamic acid (TXA) can be used after trauma to prevent bleeding. Our goal was to examine the influence of TXA on morbidity and mortality for children with severe traumatic brain injury (TBI).

METHODS

We identified children aged <18 years with a severe TBI (Glasgow Coma Scale score less than 8) presenting to 1 of the 291 hospitals contributing to the Japanese Trauma Data Bank between 2019 and 2023. The primary outcome was inhospital death, and the secondary outcome was poor neurologic outcome defined with Glasgow Outcome Scale (GOS) score of 1 to 3 at hospital discharge. Our primary exposure was any TXA administered in the hospital. Using propensity score-based inverse probability weighting, we used logistic regression to measure the association between TXA administration and death as well as poor neurologic outcome.

RESULTS

Of the 342 included patients, 30 (14%) died, and 102/225 (45%) had a GOS score less than 4 at discharge. After inverse propensity weighting, TXA administration was not associated with either mortality (adjusted odds ratio [aOR] 1.25, 95% confidence interval [CI] 0.61 to 2.54) or poor neurologic outcome (aOR 0.86, 95% CI 0.47 to 1.56).

CONCLUSIONS

TXA administration was not associated with either death or poor neurologic outcome. Prospective clinical trials of TXA usage in children with severe TBI are needed.

Association of an In-Hospital Desirability of Outcomes Ranking Scale With Postdischarge Health-Related Quality of Life: A Secondary Analysis of the Life After Pediatric Sepsis Evaluation

OBJECTIVES

To develop a desirability of outcome ranking (DOOR) scale for use in children with septic shock and determine its correlation with a decrease in 3-month postadmission health-related quality of life (HRQL) or death.

DESIGN

Secondary analysis of the Life After Pediatric Sepsis Evaluation prospective study.

SETTING

Twelve U.S. PICUs, 2013-2017.

PATIENTS

Children (1 mo-18 yr) with septic shock.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

We applied a 7-point pediatric critical care (PCC) DOOR scale: 7: death; 6: extracorporeal life support; 5: supported by life-sustaining therapies (continuous renal replacement therapy, vasoactive, or invasive ventilation); 4: hospitalized with or 3: without organ dysfunction; 2: discharged with or 1: without new morbidity to patients by assigning the highest applicable score on specific days post-PICU admission. We analyzed Spearman rank-order correlations (95% CIs) between proximal outcomes (PCC-DOOR scale on days 7, 14, and 21, ventilator-free days, cumulative 28-day Pediatric Logistic Organ Dysfunction-2 (PELOD-2) scores, and PICU-free days) and 3-month decrease in HRQL or death. HRQL was measured by Pediatric Quality of Life Inventory 4.0 or Functional Status II-R for patients with developmental delay. Patients who died were assigned the worst possible HRQL score. PCC-DOOR scores were applied to 385 patients, median age 6 years (interquartile range 2, 13) and 177 (46%) with a complex chronic condition(s). Three-month outcomes were available for 245 patients (64%) and 42 patients (17%) died. PCC-DOOR scale on days 7, 14, and 21 demonstrated fair correlation with the primary outcome (-0.42 [-0.52, -0.31], -0.47 [-0.56, -0.36], and -0.52 [-0.61, -0.42]), similar to the correlations for cumulative 28-day PELOD-2 scores (-0.51 [-0.59, -0.41]), ventilator-free days (0.43 [0.32, 0.53]), and PICU-free days (0.46 [0.35, 0.55]).

CONCLUSIONS

The PCC-DOOR scale is a feasible, practical outcome for pediatric sepsis trials and demonstrates fair correlation with decrease in HRQL or death at 3 months.

The Design of Nested Adaptive Clinical Trials of Multiple Organ Dysfunction Syndrome Children in a Single Study

OBJECTIVES

Describe the statistical design of the Personalized Immunomodulation in Sepsis-induced Multiple Organ Dysfunction Syndrome (MODS) (PRECISE) study.

DESIGN

Children with sepsis-induced MODS undergo real-time immune testing followed by assignment to an immunophenotype-specific study cohort. Interventional cohorts include the granulocyte macrophage-colony stimulating factor (GM-CSF) for the Reversal of Immunoparalysis in Pediatric Sepsis-induced MODS (GRACE)-2 trial, which uses the drug GM-CSF (or placebo) to reverse immunoparalysis; and the Targeted Reversal of Inflammation in Pediatric Sepsis-induced MODS (TRIPS) trial, which uses the drug anakinra (or placebo) to reverse systemic inflammation. Both trials have adaptive components and use a statistical framework in which frequent data monitoring assesses futility and efficacy, allowing potentially earlier stopping than traditional approaches. Prespecified simulation-based stopping boundaries are customized to each trial to preserve an overall one-sided type I error rate. The TRIPS trial also uses response-adaptive randomization, updating randomization allocation proportions to favor active arms that appear more efficacious based on accumulating data.

SETTING

Twenty-four U.S. academic PICUs.

PATIENTS

Septic children with specific immunologic derangements during ongoing dysfunction of at least two organs.

INTERVENTIONS

The GRACE-2 trial compares GM-CSF and placebo in children with immunoparalysis. The TRIPS trial compares four different doses of anakinra to placebo in children with moderate to severe systemic inflammation.

MEASUREMENTS AND MAIN RESULTS

Both trials assess primary efficacy using the sum of the daily pediatric logistic organ dysfunction-2 score over 28 days. Ranked summed scores, with mortality assigned the worst possible value, are compared between arms using the Wilcoxon Rank Sum test (GRACE-2) and a dose-response curve (TRIPS). We present simulation-based operating characteristics under several scenarios to demonstrate the behavior of the adaptive design.

CONCLUSIONS

The adaptive design incorporates innovative statistical features that allow for multiple active arms to be compared with placebo based on a child's personal immunophenotype. The design increases power and provides optimal operating characteristics compared with traditional conservative methods.

Randomized controlled trials and alternative study designs in surgical oncology

Surgery is central to the cure of most solid cancers and an integral part of modern multimodal cancer management for early and advanced stage cancers. Decisions made by surgeons and multidisciplinary team members are based on best available knowledge for the defined clinical situation at hand. While surgery is both an art and a science, good decision-making requires data that are robust, valid, representative and, applicable to most if not all patients with a specific cancer. Such data largely comes from clinical observations and registries, and more preferably from trials conducted with the specific purpose of arriving at new answers. As part of the ESSO core curriculum development an increased focus has been put on the need to enhance research literacy among surgical candidates. As an expansion of the curriculum catalogue list and to enhance the educational value, we here present a set of principles and emerging concepts which applies to surgical oncologist for reading, understanding, planning and contributing to future surgeon-led cancer trials.

Tranexamic acid in pediatric hemorrhagic trauma

ABSTRACT

There is strong evidence in adult literature that tranexamic acid (TXA) given within 3 hours from injury is associated with improved outcomes. The evidence for TXA use in injured children is limited to retrospective studies and one prospective observational trial. Two studies in combat settings and one prospective civilian US study have found association with improved mortality. These studies indicate the need for a randomized controlled trial to evaluate the efficacy of TXA in injured children and to clarify appropriate timing, dose and patient selection. Additional research is also necessary to evaluate trauma-induced coagulopathy in children. Recent studies have identified three distinct fibrinolytic phenotypes following trauma (hyperfibrinolysis, physiologic fibrinolysis, and fibrinolytic shutdown), which can be identified with viscohemostatic assays. Whether viscohemostatic assays can appropriately identify children who may benefit or be harmed by TXA is also unknown.

Prehospital Tranexamic Acid in Major Pediatric Trauma Within a Physician-Led Emergency Medical Services System: A Multicenter Retrospective Study

OBJECTIVES

Describe prehospital tranexamic acid (TXA) use and appropriateness within a major trauma pediatric population, and identify the factors associated with its use.

DESIGN

Multicenter, retrospective study, 2014-2020.

SETTING

Data were extracted from a multicenter French trauma registry including nine trauma centers within a physician-led prehospital emergency medical services (EMS) system.

PATIENTS

Patients less than 18 years old were included. Those who did not receive prehospital intervention by a mobile medical team and those with missing data on TXA administration were excluded.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Nine-hundred thirty-four patients (median [interquartile range] age: 14 yr [9-16 yr]) were included, and 68.6% n = 639) were male. Most patients were involved in a road collision (70.2%, n = 656) and suffered a blunt trauma (96.5%; n = 900). Patients receiving TXA (36.6%; n = 342) were older (15 [13-17] vs 12 yr [6-16 yr]) compared with those who did not. Patient severity was higher in the TXA group (Injury Severity Score 14 [9-25] vs 6 [2-13]; p < 0.001). The median dosage was 16 mg/kg (13-19 mg/kg). TXA administration was found in 51.8% cases ( n = 256) among patients with criteria for appropriate use. Conversely, 32.4% of patients ( n = 11) with an isolated severe traumatic brain injury (TBI) also received TXA. Age (odds ratio [OR], 1.2; 95% CI, 1.1-1.2), A and B prehospital severity grade (OR, 7.1; 95% CI, 4.1-12.3 and OR, 4.5; 95% CI, 2.9-6.9 respectively), and year of inclusion (OR, 1.2; 95% CI, 1.1-1.3) were associated with prehospital TXA administration.

CONCLUSIONS

In our physician-led prehospital EMS system, TXA is used in a third of severely injured children despite the lack of high-level of evidence. Only half of the population with greater than or equal to one criteria for appropriate TXA use received it. Conversely, TXA was administered in a third of isolated severe TBI. Further research is warranted to clarify TXA indications and to evaluate its impact on mortality and its safety profile to oversee its prescription.