Marisol Betensky, MD, on adapting pediatric VTE risk assessment

In this interview, Marisol Betensky, MD, assistant professor at Johns Hopkins Medicine, discusses the complexities of managing venous thromboembolism (VTE) risk in pediatric patients, particularly in dynamic or ambiguous clinical scenarios such as children with central venous access devices or those requiring temporary interruption of anticoagulation for procedures.

She emphasizes that pediatric hospitalization is not static; patients’ thrombotic and bleeding risks can shift significantly over time. As a result, a single risk assessment at admission is insufficient.

Instead, Betensky advocates for serial, structured reassessments throughout hospitalization—potentially supported by electronic medical record prompts every 48 to 72 hours—to capture evolving clinical factors such as new infections, immobility, or line placement. This dynamic approach allows clinicians to adjust prophylaxis strategies as patients move between low- and high-risk categories.

When managing anticoagulation around procedures, Betensky highlights the importance of balancing procedural bleeding risk—categorized as minimal, low-to-moderate, or high—against the patient’s individual thrombotic risk and the pharmacologic properties of the anticoagulant being used. Pediatric-specific considerations are critical in this context.

For example, younger children often have shorter drug half-lives, which may allow for shorter interruption intervals compared with adolescents. At the same time, the lack of widely validated reversal agents in pediatric populations necessitates careful planning. She underscores the need for standardized, institution-specific protocols that incorporate pediatric pharmacokinetics and are tailored to different age groups and clinical scenarios.

Looking toward the future of pediatric VTE research, Betensky notes that while progress has been made—demonstrated by successful randomized controlled trials such as the DIVERSITY and Kids-DOTT studies—significant methodological challenges remain. She advocates for the use of adaptive trial designs, including Bayesian approaches and innovative hybrid models that incorporate contemporaneous non-randomized control cohorts. These strategies can improve efficiency and help address the inherent limitations of small pediatric sample sizes.

Betensky also highlights the tension between narrow, condition-specific enrollment criteria and broader inclusion strategies. While focusing on homogeneous high-risk populations can yield more actionable data, it may hinder recruitment and limit generalizability.

Conversely, broader criteria enhance feasibility but risk diluting treatment effects. Adaptive enrichment designs may offer a solution by allowing trials to begin broadly and then focus on subgroups showing the strongest signals of benefit.

Finally, she stresses the importance of age stratification in trials because of developmental differences in hemostasis and drug metabolism. Recognizing that clinical trials alone cannot meet all evidence needs, Betensky calls for continued investment in collaborative research infrastructure and real-world data registries. Together, these efforts will be essential for generating the high-quality, pediatric-specific evidence needed to guide safe and effective thromboprophylaxis.

This video is part 2 of a 2-part series. Click here for part 1.

No relevant disclosures.

Reference

ASH and ISTH publish new clinical practice guidelines on anticoagulant prophylaxis in pediatric patients at risk of blood clots. American Society of Hematology. April 8, 2026. Accessed April 20, 2026. https://www.eurekalert.org/news-releases/1122908?