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HIT-It or Quit It: Heparin-Induced Thrombocytopenia Testing Appropriateness Using 4T Scoring and Inappropriate
Megan Sears-Smith1, Emily Ely Daniels1, Daphne Norwood1
1From the Departments of Internal Medicine and Surgery, University of Tennessee Medical Center Graduate School of Medicine, Knoxville.
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.
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