Use of a computer-based provider order entry (CPOE) intervention to optimize laboratory testing in patients with suspected heparin-induced thrombocytopenia

Introduction: Heparin-induced thrombocytopenia (HIT) is a rare but frequently considered diagnosis in hospitalized patients. Despite the availability of clinical prediction tools, HIT is often over-diagnosed and patients can be subjected to unnecessary and expensive testing. Methods: A decision-support tool requiring providers to calculate the 4Ts (HIT risk) score prior to ordering laboratory-based tests for anti-PF4/heparin antibody enzyme-linked immunosorbent assay (ELISA) testing was implemented at our institution in January 2014. Charts of adult patients who underwent ELISA or serotonin release assay (SRA) testing during the 8-month time periods prior to and following this intervention were reviewed and 4Ts scores at the time of ELISA or SRA testing were calculated. Results: A total of 443 ELISA and SRA tests were sent for 411 patients during the time periods studied. We observed a significant decrease from 43 tests/month before to 22 tests/month (p b 0.001) after the intervention. A total of 337 charts were reviewed. We observed a trend toward decrease in the proportion of tested patients with low 4Ts scores (66% vs 56%, p = 0.069), as well as an increase in the average 4Ts score of tested patients (3.0 vs 3.4, p = 0.010) following our intervention. Discussion: Over-testing and treatment for HIT are frequent and potentially harmful occurrences in hospitalized patients. Our study demonstrates that a clinical decision support tool embedded within the electronic ordering process can decrease unnecessary testing for HIT.