The phase 3 pediatric anticoagulant era

How I treat pediatric venous thromboembolism in the DOAC era

ABSTRACT

The direct oral anticoagulants (DOACs) rivaroxaban and dabigatran are newly licensed for the treatment and prevention of venous thromboembolism (VTE) in children and mark a renaissance in pediatric anticoagulation management. They provide a convenient option over standard-of-care anticoagulants (heparins, fondaparinux, and vitamin K antagonists) because of their oral route of administration, child-friendly formulations, and significant reduction in monitoring. However, limitations related to therapeutic monitoring when needed and the lack of approved reversal agents for DOACs in children raise some safety concerns. There is accumulating experience of safety and efficacy of DOACs in adults for a broad scope of indications; however, the cumulative experience of using DOACs in pediatrics, specifically for those with coexisting chronic illnesses, is sparse. Consequently, clinicians must often rely on their experience for treating VTE and extrapolate from data in adults while using DOACs in children. In this article, the authors share their experience of managing 4 scenarios that hematologists are likely to encounter in their day-to-day practice. Topics addressed include (1) appropriateness of indication; (2) use for special populations of children; (3) considerations for laboratory monitoring; (4) transition between anticoagulants; (5) major drug interactions; (6) perioperative management; and (7) anticoagulation reversal.

Hemostatic and thrombotic disorders in the pediatric patient

This review focuses on significant advances in the field of pediatric hemostasis and thrombosis, with a focus on published studies within the past decade. The evaluation and management of patients with excessive bleeding remain cornerstones of consultative hematology. We will describe the development of validated bleeding assessment tools relevant to pediatric practice, laboratory advances in the evaluation of von Willebrand disease, and a shift in clinical practice regarding the interpretation of normal coagulation studies in patients with significant bleeding phenotypes. There have also been critical advances in the management of hemostatic disorders. This review highlights new treatment paradigms in hemophilia and the rise of multidisciplinary medical homes for women living with bleeding disorders. Given the continued increase in the incidence of thrombosis, particularly in the hospital setting, a full call to arms against pediatric venous thromboembolism is now essential. We will describe recently completed clinical trials of direct oral anticoagulants in children and adolescents and ongoing work to elucidate the appropriate duration of therapy for children with provoked thrombosis. Recent work regarding the prevention of pediatric venous thromboembolism is highlighted, including studies of thromboprophylaxis and the development of risk prediction models for hospital-acquired thrombosis. Finally, we review advances in our understanding of thrombotic sequelae and the need for continued refinement of our evaluation tools. Despite the significant advances in pediatric hemostasis and thrombosis over the past decade, many unanswered questions remain for the next generation of investigators.

Community-Onset Venous Thromboembolism in Children: Pediatric Emergency Medicine Perspectives

Pediatric venous thromboembolism (VTE) is a condition increasingly encountered by emergency medicine physicians. Unfortunately, despite increased incidence, the diagnosis of pediatric VTE relies on a high index of suspicion from clinicians. Delays in diagnosis and initiation of treatment can lead to poor outcomes in children, including an increased risk of mortality from pulmonary embolism, increased risk of VTE recurrence, and the development of the post-thrombotic syndrome. The majority of pediatric VTE events are associated with the presence of at least one underlying prothrombotic risk. Timely recognition of these risk factors in the emergency department (ED) setting is paramount for a prompt diagnosis and treatment initiation. Compared with children with hospital-acquired VTE, children presenting to the ED with new onset VTE tend to be older (>11 years of age), have a lower incidence of co-morbidities, and present more frequently with a deep venous thrombosis of the lower extremity. Currently, there are no validated pediatric-specific VTE clinical pretest probability tools that reliably assist with the accurate and timely diagnosis of pediatric VTE. Compression ultrasound with Doppler is the most common imaging modality used for VTE diagnosis, and low molecular weight heparins are the most common anticoagulants initiated in children presenting with VTE in the ED. Special consideration should be given to patients who present to the ED already on anticoagulation therapy who may require acute management for clinically-significant bleeding or change in antithrombotic therapy approach for progression/recurrence of VTE.