Background: The need to rapidly evaluate patients presenting to emergency departments and cardiology services for ruling in and ruling out acute myocardial infarction (AMI) is widely recognized as a clinical challenge. We determined the impact of incorporating point-of-care (POC) cardiac troponin I (cTnI) testing into a cardiology service regarding assay turn around time (TAT), patient length of stay (LOS), financial matrixes and patient outcomes compared to central laboratory cTnI testing.
Methods: Patients presenting with symptoms suggestive of acute coronary syndrome (ACS) were enrolled pre-POC (PreCS, n=271) and post-POC (PostCS, n=274). POC cTnI determinations were performed at the bedside on the Dade Behring Stratus CS by nursing staff. Routine cTnI determinations were performed in the central laboratory (Dade Behring Dimension) by laboratory staff. Data were collected and analyzed on each patient per hospital stay by review of electronic medical and financial records. In addition, risk stratification outcomes for all cause death were determined at 30 days and 1 y following baseline sampling based on the 99th percentile cutoff concentrations of <0.1 microg/l for both assays.
Results: There was a decrease in time from blood draw to result to healthcare provider (PreCS mean 76 min; PostCS mean 19.5 min; p<0.001) as well as a decrease trend in charge per patient admission (4281 dollars savings) following implementation of POC testing. Total charges per patient admission decreased by 25% PostCS vs. PreCS (17,163 dollars vs. 12,882 dollars); a composite of lower charges for: boarding (-21%), other departments (-58%), pharmacy (-28%), labs (-22%), non-cardiac procedures (-28%), cardiac procedures (-14%). The mean LOS also decreased 8% (p=0.05) from PreCS (2.36 days) to PostCS (2.19 days). cTnI reagents charges to the laboratory were higher for the POC assay, 10.54 dollars, vs. the central lab assay, 3.83 dollars. One year survival was greater in the <0.1 microg/l patients (PreCS 96.2%, PostCS 97.2%) compared to the >0.1 microg/l patients (PreCS 77.7%, PostCS 75.5%); both p<0.001. Kaplan-Meier survival curves showed early separation by 30 days in each group.
Conclusions: Our study demonstrates the cost effectiveness and clinical effectiveness of implementation of POC whole blood, cTnI testing for assisting clinicians with diagnostic and risk assessment of ACS patients.