Original Article

HIT-It or Quit It: Heparin-Induced Thrombocytopenia Testing Appropriateness Using 4T Scoring and Inappropriate Testing Cost Analysis

Authors: Megan Sears-Smith, DO, Emily Ely Daniels, DO, Daphne Norwood, MD, MPH, Eric R. Heidel, PhD

Abstract

Objectives: The American Society of Hematology’s 4T scoring system is a validated tool to assess a patient’s probability of having heparin-induced thrombocytopenia (HIT) before testing is performed. There is no benefit to testing patients with a low probability 4T score for HIT. This study aimed to assess for inappropriate HIT testing at our institution based on 4T scoring.

Methods: We retrospectively reviewed 201 patient charts and calculated 4T scores and testing costs to assess for inappropriate testing and the economic impact of such testing.

Results: HIT testing often occurred in the least appropriate patients and resulted in tens of thousands of dollars of waste for unnecessary testing.

Conclusions: Inappropriate testing for HIT is still a prevalent issue despite literature supporting the 4T score for guidance in testing appropriateness.
Posted in: Hematology10

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References

1. Salter BS, Weiner MM, Trinh MA, et al. Heparin-induced thrombocytopenia: a comprehensive clinical review. J Am Coll Cardiol 2016;67:2519–2532.
 
2. Cuker A, Gimotty PA, Crowther MA, et al. Predictive value of the 4Ts scoring system for heparin-induced thrombocytopenia: a systematic review and meta-analysis. Blood 2012;120:4160–4167.
 
3. Hasan M, Malalur P, Agastya M, et al. A high-value cost conscious approach to minimize heparin induced thrombocytopenia antibody (HITAb) testing using the 4T score. J Thromb Thrombolysis 2016;42:441–446.
 
4. Farley S, Cummings C, Heuser W, et al. Prevalence and overtesting of true heparin-induced thrombocytopenia in a 591-bed tertiary care, teaching hospital. J Intensive Care Med 2017;34:464–471.
 
5. American Society of Hematology. Don’t test or treat for suspected heparin-induced thrombocytopenia (HIT) in patients with a low pre-test probability of HIT. https://www.choosingwisely.org/clinician-lists/american-society-hematology-testing-treating-suspected-heparin-induced-thrombocytopenia/. Published December 2014. Accessed April 25, 2021.
 
6. Lo GK, Juhl D, Warkentin TE, et al. Evaluation of pretest clinical score (4 T’s) for the diagnosis of heparin-induced thrombocytopenia in two clinical settings. J Thromb Haemost 2006;4:759–765.
 
7. Pauzner R, Greinacher A, Selleng K, et al. False-positive tests for heparin-induced thrombocytopenia in patients with antiphospholipid syndrome and systemic lupus erythematosus. J Thromb Haemost 2009;7:1070–1074.
 
8. Shrank W, Rogstad T, Parekh N. Waste in the US healthcare system estimated costs and potential for savings. JAMA 2019;322:1501–1509.
 
9. Gearing RE, Mian IA, Barber J, et al. A methodology for conducting retrospective chart review research in child and adolescent psychiatry. J Can Acad Child Adolesc Psychiatry 2006;15:126–134.
 
10. Vassar M, Holzmann M. The retrospective chart review: important methodological considerations. J Educ Eval Health Prof 2013;10:12.