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Point-of-care testing for coagulation studies in a stroke protocol: a time-saving innovation
Michael J Drescher1, Andrea Spence, Darryl Rockwell
1Hartford Hospital, University of Connecticut, 06102, USA. mdresch@harthosp.org
The American Journal of Emergency Medicine
|September 10, 2010
Summary
Point-of-care testing (POCT) for international normalized ratio (INR) in the emergency department accurately guides thrombolytic therapy for stroke. This method can reduce treatment delays, improving patient outcomes.
Area of Science:
- Emergency Medicine
- Clinical Pathology
- Pharmacology
Background:
- Thrombolytic therapy is crucial for stroke treatment, but time is critical.
- An international normalized ratio (INR) above 1.7 often contraindicates this therapy.
- Rapid INR assessment is needed in the emergency department (ED) to expedite treatment decisions.
Purpose of the Study:
- To evaluate the efficacy of point-of-care testing (POCT) for INR measurement in the ED.
- To determine if POCT INR can replace central laboratory testing, thereby reducing treatment initiation time.
- To assess the accuracy of POCT INR compared to central laboratory results for patients on warfarin.
Main Methods:
- A prospective observational study was conducted comparing POCT INR (i-STAT-1) with central laboratory INR.
- Simultaneously drawn blood samples were used for both tests.
- Adult patients taking warfarin presenting to the ED of a tertiary teaching hospital were included.
Main Results:
- The study included 32 patients. Receiver operator curve analysis showed excellent performance (Area Under Curve = 0.979).
- POCT INR of 2.1 achieved 100% sensitivity and 90.5% specificity for detecting a laboratory INR > 1.7.
- POCT INR of 1.8 demonstrated 100% specificity and 62.5% sensitivity for detecting a laboratory INR < 1.7. Regression coefficient (r) was 0.9648.
Conclusions:
- POCT INR demonstrates excellent correlation with central laboratory results.
- POCT INR values are generally slightly higher (approx. 0.3) than laboratory values, which may be clinically significant around the 1.7 cutoff.
- A tiered system using POCT INR is proposed to facilitate timely decisions regarding tissue-type plasminogen activator administration in stroke patients.
