title: Validation of a continuous, arterial pressure-based cardiac output measurement: a multicenter, prospective clinical trial.
abstract: BACKGROUND
  The present study compared measurements of cardiac output by an arterial pressure-based cardiac output (APCO) analysis method with measurement by intermittent thermodilution cardiac output (ICO) via pulmonary artery catheter in a clinical setting.
  
  
  METHODS
  The multicenter, prospective clinical investigation enrolled patients with a clinical indication for cardiac output monitoring requiring pulmonary artery and radial artery catheters at two hospitals in the United States, one hospital in France, and one hospital in Belgium. In 84 patients (69 surgical patients), the cardiac output was measured by analysis of the arterial pulse using APCO and was measured via pulmonary artery catheter by ICO; to establish a reference comparison, the cardiac output was measured by continuous cardiac output (CCO). Data were collected continuously by the APCO and CCO technologies, and at least every 4 hours by ICO. No clinical interventions were made as part of the study.
  
  
  RESULTS
  For APCO compared with ICO, the bias was 0.20 l/min, the precision was +/- 1.28 l/min, and the limits of agreement were -2.36 l/m to 2.75 l/m. For CCO compared with ICO, the bias was 0.66 l/min, the precision was +/- 1.05 l/min, and the limits of agreement were -1.43 l/m to 2.76 l/m. The ability of APCO and CCO to assess changes in cardiac output was compared with that of ICO. In 96% of comparisons, APCO tracked the change in cardiac output in the same direction as ICO. The magnitude of change was comparable 59% of the time. For CCO, 95% of comparisons were in the same direction, with 58% of those changes being of similar magnitude.
  
  
  CONCLUSIONS
  In critically ill patients in the intensive care unit, continuous measurement of cardiac output using either APCO or CCO is comparable with ICO. Further study in more homogeneous populations may refine specific situations where APCO reliability is strongest.
authors: Critical Care Division, Baystate Medical Center, 759 Chestnut Street, Springfield, MA 01199, USA. william.t.mcgee@bhs.org
authors: William T
authors: WT
authors: McGee
authors: Jeffrey L
authors: JL
authors: Horswell
authors: Joachim
authors: J
authors: Calderon
authors: Gerard
authors: G
authors: Janvier
authors: Tom
authors: T
authors: Van Severen
authors: Greet
authors: G
authors: Van den Berghe
authors: Lori
authors: L
authors: Kozikowski
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001795:Blood Pressure Determination / Q000295:instrumentation / Q000379:methods; D002302:Cardiac Output; D002407:Catheterization, Swan-Ganz; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000295:instrumentation / Q000379:methods*; D011446:Prospective Studies; D017534:Radial Artery; D015203:Reproducibility of Results