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Updated: Sep 2, 2026

Hemodynamic Precision in the Neonatal Intensive Care Unit using Targeted Neonatal Echocardiography
Published on: January 27, 2023
Redefining neonatal thrombocytopenia: an evidence-based approach, improved by the refineR algorithm
Bailey B Zeiler1, Timothy M Bahr2,3, Kelly Doyle4
1Division of Neonatology, Department of Pediatrics, University of Utah, Salt Lake City, UT, USA. bailey.zeiler@hsc.utah.edu.
Objective:
A common definition of neonatal thrombocytopenia is a platelet count <150,000/µL. The international hematologic consensus designation of cytopenia is a blood count <2.5th percentile lower reference interval for an appropriate comparison population. We hypothesized that a new reference interval modeling algorithm, refineR, would generate more accurate platelet reference intervals and, therefore, more accurate and evidence-based definitions of neonatal thrombocytopenia.
Study Design:
We utilized refineR to analyze platelet counts from large clinical databases to generate new neonatal platelet reference intervals.
Results:
With 155,062 neonatal platelet counts, we created reference intervals for the day of birth and over the first 30 days. These included a lower (2.5th percentile) reference interval at birth for neonates ≥34 weeks of 119,600 platelets/µL (95% CI, 117,700 to 135,300/µL) and for neonates <34 weeks of 103,000 platelets/µL (98,700 to 105,600).
Conclusion:
Platelet counts of neonates at birth in the range of 120,000-150,000/µL are normal.
