This Article Full Text (PDF) References Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Citing Articles Citing Articles via Google Scholar Citing Articles via Scopus Google Scholar Articles by Dorfman, D. M Articles by Goldhaber, S. Z Search for Related Content PubMed PubMed Citation Articles by Dorfman, D. M Articles by Goldhaber, S. Z Pubmed/NCBI databases Compound via MeSH Substance via MeSH Medline Plus Health Information Blood Thinners Hazardous Substances DB WARFARIN Social Bookmarking                         What's this?

Point-of-care (POC) versus central laboratory instrumentation for monitoring oral anticoagulation

Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA, ddorfman{at}partners.org

Ellen M Goonan

Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA

M Kay Boutilier

Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA

Petr Jarolim

Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA

Milenko Tanasijevic

Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA

Samuel Z Goldhaber

Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA

Point-of-care (POC) instruments employing fingerstick whole blood to monitor patients treated with warfarin are a popular alternative to complex, central laboratory coagulation analyzers utilizing citrated plasma derived from venipuncture. We investigated the accuracy of two widely utilized POC instruments for oral anticoagulation monitoring compared with a central laboratory instrument. Instrument-to-instrument variation differed for the two POC instruments, which correlated with the central laboratory instrument, but exhibited positive bias of 0.24-0.35 INR units. Positive bias increased as the INR values increased. We conclude that clinicians should exercise caution when interpreting results generated by POC monitors, particularly at high INR values. A high POC measurement of INR does not necessarily warrant decreasing the warfarin dose. Instead, a predefined cut-off range for high INR values generated by POC instruments should mandate confirmatory testing with central laboratory instrumentation.

Key Words: international normalized ratio (INR) • prothrombin time (PT) • warfarin

Vascular Medicine, Vol. 10, No. 1, 23-27 (2005)
DOI: 10.1191/1358863x05vm587oa


CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?