2026 Critical Care Congress Skip to main content
2026 Critical Care Congress Main banner
Final Program


Advance Program
Icon Legend
This session is not in your schedule.
This session is in your schedule. Click again to remove it.
Session Icons
Thought Leader Session
Thought Leader Session
Guidelines Session
Guidelines Session
Aging Adult Track
Aging Adult Track
Additional Registration Fee
Additional Registration Fee

Research Snapshot Theater: Cardiovascular, Pediatric II

Variable Clopidogrel Response in Pediatric Patients: A Call for Monitoring

Tuesday, March 24, 2026
10:00 AM - 11:00 AM Central Time
Location: Connections Central - RST 07
  • NS

    Nina Srour, PharmD

    Seattle Children's Hospital, Washington

    Disclosure(s): No relevant financial relationship(s) to disclose.

  • QN

    Quynh Nguyen, PharmD

    Clinical Pharmacist, Pediatric ICU
    Seattle Children's Hospital

    Disclosure information not submitted.

  • BW

    Bethany Wisotzkey, MD

    Pediatric Cardiologist
    Seattle Children's Hospital

    Disclosure information not submitted.

  • DN

    David Newland, PharmD

    Clinical Pharmacist, SOT
    Seattle Children's Hospital

    Disclosure information not submitted.

  • Ndidi Musa, MD, , FCCM

    Seattle Children's Hospital, Washington

    Disclosure information not submitted.

  • AR

    Agustin Rubio, MD

    Pediatric Cardiologist
    Seattle Children's Hospital

    Disclosure information not submitted.

Introduction: Clopidogrel is often used in pediatric patients at risk of thrombosis, particularly those with intracardiac stents or a Berlin Heart device. Both poor and excessive response to clopidogrel have been linked to thrombosis and bleeding. While platelet function tests like the VerifyNow –P2Y12 (VN) assay are increasingly available, their role in guiding pediatric dosing remains unclear. This study evaluated institutional practices in clopidogrel use and monitoring, and their impact on clinical outcomes.


Methods: A retrospective, descriptive study proposal was submitted to Seattle Children’s Hospital IRB to review patients ≤18 years old who received clopidogrel between October 2020 and April 2025. Demographic data along with diagnoses were collected. Primary endpoints included initial dosing, VN assay response, and subsequent dosing adjustments; secondary outcomes were bleeding and thrombotic events. Patients were stratified by age into three groups: < 2, 2 -10 and > 10 years.


Results: Among 46 patients who received clopidogrel, median initial doses were 0.2 mg/kg/day [IQR 0.2-0.2], 1 [0.66-1], and 1.12 [0.96-1.3] for patients < 2 (n=26), 2 -10 years (n=9) and >10 years (n=11), respectively. VN testing was performed in 57% (26/46), identifying 42% (11/26) as hyper-responders (VN < 80), 38% (10/26) as hypo-responders (VN>180), and 19% (5/26) with adequate response (VN 80-180). Dosing was adjusted in 54% (14/26) of those tested.

Overall, 39% (18/46) of patients required dose changes: 8 dose increases, 4 reductions, and 6 therapy discontinuations due to bleeding. Final doses among those who continued therapy (n=40) were 0.2 mg/kg/day [IQR 0.2 - 0.36], 1 [0.75-1.14], and 1.13 [1 - 1.33] in the respective age groups.

Bleeding occurred in 22% (10/46) of patients; among those with VN testing, all had VN < 80. Thrombotic events occurred in 24% (11/46) of patients, primarily among those with VN >180.


Conclusions: Clopidogrel dosing and response varied across pediatric age groups. Platelet function testing often revealed suboptimal response, prompting dose changes in over half of tested patients. Bleeding was linked with hyper-responsiveness (VN < 80), and thrombosis to hypo-responsiveness (VN>180), supporting the need for monitoring to guide safer and individualized dosing.