In vitro tests for assessing heparin-induced thrombocytopenia in patients after elective hip replacement. A medico-economical evaluation.
OBJECTIVE
Considering the previously published incidences of heparin-induced thrombocytopenia (HIT) in patients receiving a thromboprophylactic therapy, the role of the hemostasis laboratory is essential in making a clinical decision. The purpose of this project was to compare the strategies of diagnosis and associated care of patients with suspected HIT after elective hip replacement using platelet aggregation assay, carbon 14-serotonin release, and "doing nothing."


METHODS
The authors used an incremental cost-effectiveness analysis based on data extracted from the literature. The effectiveness of the strategies was represented by the number of deep venous thromboses prevented. Cost data were collected from the observation of biological and medical practice at Edouard Herriot University Hospital, Lyon, France, in 1999.


RESULTS
In comparison with the strategies of doing nothing using no biological test for diagnosis, and clinical care of HIT-suspected patients, the strategy using platelet aggregation test was more expensive and less effective. With respect to the strategy using carbon 14-serotonin release assay, the incremental cost-effectiveness ratio, expressed as U.S. dollars per deep venous thrombosis prevented, reached $200,000, with a marginal effectiveness of eight deep venous thromboses prevented for 10,000 HIT-suspected patients.


CONCLUSIONS
This study suggests that clinical hemostasis laboratories might consider replacing the platelet aggregation test with the carbon 14-serotonin release assay or should use another functional assay such as the flow cytometric assay for the diagnosis and care of patients with suspected HIT.
Sobas
Frédéric
F
Edouard Herriot University Hospital, Lyon, France.
Colin
Cyrille
C
Ffrench
Patrick
P
Trzeciak
Marie Christine
MC
Dechavanne
Marc
M
Négrier
Claude
C
D000925:Anticoagulants / Q000009:adverse effects* / Q000378:metabolism; D019644:Arthroplasty, Replacement, Hip; D002250:Carbon Radioisotopes / Q000191:economics; D019411:Clinical Laboratory Techniques / Q000191:economics*; D003362:Cost-Benefit Analysis; D003661:Decision Support Techniques; D005602:France; D006488:Hemostasis, Surgical; D006493:Heparin / Q000009:adverse effects* / Q000378:metabolism; D017721:Hospital Costs / Q000706:statistics & numerical data*; D006801:Humans; D066298:In Vitro Techniques; D010974:Platelet Aggregation / Q000187:drug effects; D010978:Platelet Factor 4 / Q000378:metabolism; D010979:Platelet Function Tests / Q000191:economics* / Q000379:methods; D012680:Sensitivity and Specificity; D012701:Serotonin / Q000097:blood* / Q000378:metabolism; D013921:Thrombocytopenia / Q000139:chemically induced / Q000175:diagnosis* / Q000378:metabolism; D020246:Venous Thrombosis / Q000191:economics* / Q000517:prevention & control*
D000925:Anticoagulants; D002250:Carbon Radioisotopes; D012701:Serotonin; D010978:Platelet Factor 4; D006493:Heparin