title: Comparability of Results between Point-of-Care and Automated Instruments to Measure B-type Natriuretic Peptide.
abstract: OBJECTIVE
  Heart failure is one of the leading causes of death in the U.S. The incorporation of B-type natriuretic peptide (BNP) measurements when triaging patients presenting with shortness of breath has improved the diagnostic and prognostic ability of physicians. Currently, there are no point-of-care systems for quantifying BNP that can be used without sacrificing accuracy. We compared the analytical performance of the Abbott i-STAT analyzer, a handheld point-of-care system for measuring BNP, with the lab-based system, the Abbott ARCHITECT.
  
  
  METHODS
  One-hundred fifty samples were collected from three clinical settings: 41 from the Emergency Department, 58 from the inpatient wards, and 51 from heart failure outpatient clinics. Linear regression and bias difference analyses were run to evaluate the accuracy of the i-STAT. Correlation between the i-STAT and Architect BNP values were made with values of BNP.
  
  
  RESULTS
  The correlation coefficient was r=0.977 (N=150, p<.0001). The average bias was significant (-36) and there were concentration-dependent differences at higher BNP values. Precision of the i-STAT was poor compared to the lab-based platform.
  
  
  CONCLUSIONS
  Although the precision of the i-STAT was poor, there was good clinical agreement between the i-STAT and the lab-based platform.
authors.affiliation: Veterans Administration San Diego Healthcare System, Cardiology, La Jolla, CA.
authors.forename: Kevin
authors.initials: K
authors.lastname: Shah
authors.forename: Garrett J
authors.initials: GJ
authors.lastname: Terracciano
authors.forename: Kevin
authors.initials: K
authors.lastname: Jiang
authors.forename: Alan S
authors.initials: AS
authors.lastname: Maisel
authors.forename: Robert L
authors.initials: RL
authors.lastname: Fitzgerald
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