Cost effectiveness of in-house HIT screening testing in community based hospital Free

Background Heparin-induced thrombocytopenia type II (HIT) is a rare but potentially life-threatening immune-mediated complication encountered in hospitalized patients. Many community hospitals rely on outsourced laboratories for HIT testing, resulting in longer turnaround times. This often necessitates empiric anticoagulation while awaiting results, leading to prolonged exposure to parenteral anticoagulation, increased bleeding risk, and overall elevated healthcare costs. Many community-based teaching hospitals order high enough tests to justify in-house testing. This quality improvement project implemented in-house HIT testing of patients admitted to the Community Health Partners hospitals in Central Valley of California. Retrospective chart review was done to evaluate the impact of implementing in-house HIT screening tests on the turnaround time, frequency of empiric anticoagulation use, confirmatory test ordering, and the financial burden of anticoagulation.

Methods Following the identification of HIT testing and management as an area that needs optimization, a trainee-led committee was set up to evaluate workflow improvement and the feasibility of in-house testing. A workflow of in-house screening test, with a reflex outsourced confirmatory test if needed, staff training, and final project implementation took place in May 2024. Retrospective chart review was conducted of patients with suspected HIT who underwent testing before and after the implementation of in-house screening. Pre-intervention group (Group A) included patients tested during January 1, 2018 to December 31, 2018 and January 1, 2023 to December 31, 2023. Post-intervention group (Group B) included patients tested between June 1, 2024 to January 31, 2025. Confirmatory tests were outsourced in both groups. Collected variables included time to screening and confirmatory test results, test outcomes, empiric anticoagulation usage, and type of anticoagulants administered. Descriptive statistics and chi-square tests (via SPSS software) were used to assess confirmatory test order and empiric anticoagulation usage. Mann-Whitney U test was used to compare differences in turnaround time between the groups.

Results Group A included 510 patients, of whom 75 (14.7%) had positive screening tests. Total of 117 (22.9%) confirmatory tests were ordered, of which 16 (13.7%) were positive. The average turnaround time for screening result was 3.12 days. Empiric anticoagulation was initiated in 147 (28.8%) patients, with argatroban in 85 (57.8%), fondaparinux in 50 (34.0%), and 12 (8.2%) receiving other anticoagulants (apixaban, rivaroxaban, or bivalirudin).

Group B included 258 patients, of whom 28 (10.9%) had positive screening tests. Total of 39 (15.1%) confirmatory tests were ordered, of which 10 (25.6%) were positive. The average turnaround time for screening result was significantly shorter at 1.02 days. Only 48 (18.6%) patients received empiric anticoagulation, with argatroban used in 25 (52.1%), fondaparinux in 17 (35.4%), and other anticoagulants (apixaban and bivalirudin) in 6 (12.5%).

Group A had a higher rate of confirmatory test orders (22.9%) compared to Group B (15.1%, p = 0.011), likely due to the longer anticipated delay in send-out screening results, prompting early confirmatory testing. The mean turnaround time for screening was significantly reduced from 3.12 days (Group A) to 1.02 days (Group B, p < 0.0001). Empiric anticoagulation was used less frequently in Group B (18.6%, p = 0.002) than Group A (28.8%), possibly due to the anticipated shorter turnaround time in Group B, allowing clinicians to defer anticoagulation until results were available. This reduction in empiric anticoagulation use may help avoid unnecessary treatment in thrombocytopenic patients without HIT, improving patient safety and outcomes. A cost analysis based on drug usage over a 12-month period showed that anticoagulation costs were significantly lower in Group B ($7,610) compared to Group A ($24,791), assuming an average patient weight of 80 kg and using current drug pricing. The implementation of in-house HIT screening tests resulted in an annual cost saving of $17,181 in anticoagulation alone.

Conclusion Implementation of the HIT testing algorithm using an in-house screening test with a reflex outsourced confirmatory test resulted in decreased turnaround time, reduction of empiric anticoagulation utilization, and potential cost savings for hospitalized patients with suspected HIT.