Efficacy and Safety of Antifibrinolytic Drugs in Pediatric Surgery: A Systematic Review

Perioperative considerations in the paediatric patient with congenital and acquired coagulopathy

Neonates, infants, and children undergoing major surgery or with trauma can develop severe coagulopathy perioperatively. Neonates and infants are at highest risk because their haemostatic system is not fully developed and underlying inherited bleeding disorders may not have been diagnosed before surgery. Historically, laboratory coagulation measurements have been used to diagnose and monitor coagulopathies. Contemporary dynamic monitoring strategies are evolving. Viscoelastic testing is increasingly being used to monitor coagulopathy, particularly in procedures with a high risk of bleeding. However, there is a lack of valid age-specific reference values for diagnosis and trigger or target values for appropriate therapeutic management. A promising screening tool of primary haemostasis that may be used to diagnose quantitative and qualitative platelet abnormalities is the in vitro closure time by platelet function analyser. Targeted individualised treatment strategies for haemostatic bleeding arising from inherited or acquired bleeding disorders may include measures such as tranexamic acid, administration of plasma, derived or recombinant factors such as fibrinogen concentrate, or allogeneic blood component transfusions (plasma, platelets, or cryoprecipitate). Herein we review current recommended perioperative guidelines, monitoring strategies, and treatment modalities for the paediatric patient with a coagulopathy. In the absence of data from adequately powered prospective studies, it is recommended that expert consensus be considered until additional research and validation of goal-directed perioperative bleeding management in paediatric patients is available.

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.

Efficacy and utility of antifibrinolytics in pediatric spine surgery: a systematic review and network meta-analysis

Antifibrinolytics have gained increasing attention in minimizing blood loss and mitigating the risks associated with massive transfusions, including infection and coagulopathy in pediatric patients undergoing spine surgery. Nevertheless, the selection of optimal agent is still a matter of debate. We aim to review the utility of these agents and compare the efficacy of antifibrinolytics in pediatric and adolescent spine surgeries. A comprehensive search was performed in Scopus, Web of Science, and MEDLINE databases for relevant works. Studies providing quantitative data on predefined outcomes were included. Primary outcome was perioperative bleeding between the groups. Secondary outcomes included transfusion volume, rate of complications, and operation time. Twenty-eight studies were included in the meta-analysis incorporating 2553 patients. The use of Tranexamic acid (RoM: 0.71, 95%CI: [0.62-0.81], p < 0.001, I2 = 88%), Aprotinin (RoM: 0.54, 95%CI: [0.46-0.64], p < 0.001, I2 = 0%), and Epsilon-aminocaproic acid (RoM: 0.71, 95%CI: [0.62-0.81], p < 0.001, I2 = 60%) led to a 29%, 46%, and 29% reduction in perioperative blood loss, respectively. Network meta-analysis revealed higher probability of efficacy with Tranexamic acid compared to Epsilon-aminocaproic acid (P score: 0.924 vs. 0.571). The rate of complications was not statistically different between each two antifibrinolytic agent or antifibrinolytics compared to placebo or standard of care. Our network meta-analysis suggests a superior efficacy of all antifibrinolytics compared to standard of care/placebo in reducing blood loss and transfusion rate. Further adequately-powered randomized clinical trials are recommended to reach definite conclusion on comparative performance of these agents and to also provide robust objective assessments and standardized outcome data and safety profile on antifibrinolytics in pediatric and adolescent pediatric surgeries.

Traumatic injury clinical trial evaluating tranexamic acid in children (TIC-TOC): A pilot randomized trial

BACKGROUND

The antifibrinolytic drug tranexamic acid (TXA) improves survival in adults with traumatic hemorrhage; however, the drug has not been evaluated in a trial in injured children. We assessed the feasibility of a large-scale trial evaluating the effects of TXA in children with severe hemorrhagic injuries.

METHODS

Severely injured children (0 up to 18th birthday) were randomized into a double-blind randomized trial of (1) TXA 15 mg/kg bolus dose, followed by 2 mg/kg/h infusion over 8 h, (2) TXA 30 mg/kg bolus dose, followed by 4 mg/kg/h infusion over 8 h, or (3) normal saline placebo bolus and infusion. The trial was conducted at four pediatric Level I trauma centers in the United States between June 2018 and March 2020. We enrolled patients under federal exception from informed consent (EFIC) procedures when parents were unable to provide informed consent. Feasibility outcomes included the rate of enrollment, adherence to intervention arms, and ability to measure the primary clinical outcome. Clinical outcomes included global functioning (primary), working memory, total amount of blood products transfused, intracranial hemorrhage progression, and adverse events. The target enrollment rate was at least 1.25 patients per site per month.

RESULTS

A total of 31 patients were randomized with a mean age of 10.7 years (standard deviation [SD] 5.0 years) and 22 (71%) patients were male. The mean time from injury to randomization was 2.4 h (SD 0.6 h). Sixteen (52%) patients had isolated brain injuries and 15 (48%) patients had isolated torso injuries. The enrollment rate using EFIC was 1.34 patients per site per month. All eligible enrolled patients received study intervention (nine patients TXA 15 mg/kg bolus dose, 10 patients TXA 30 mg/kg bolus dose, and 12 patients placebo) and had the primary outcome measured. No statistically significant differences in any of the clinical outcomes were identified.

CONCLUSION

Based on enrollment rate, protocol adherence, and measurement of the primary outcome in this pilot trial, we confirmed the feasibility of conducting a large-scale, randomized trial evaluating the efficacy of TXA in severely injured children with hemorrhagic brain and/or torso injuries using EFIC.

The Year in Review: Anesthesia for Congenital Heart Disease 2021

This review focuses on the literature published during the calendar year 2021 that is of interest to anesthesiologists taking care of children and adults with congenital heart disease. Four major themes are discussed, including cardiovascular disease in children with COVID-19, aortic valve repair and replacement, bleeding and coagulation, and enhanced recovery after surgery (ERAS).