title: Continuous cardiac output monitoring with pulse contour analysis: a comparison with lithium indicator dilution cardiac output measurement.
abstract: OBJECTIVE
  Pulse contour analysis can be used to provide beat-to-beat cardiac output (CO) measurement. The current study sought to evaluate this technique by comparing its results with lithium dilution CO (LiCO) measurements.
  
  
  METHODS
  Prospective, observational study.
  
  
  METHODS
  Surgical intensive care unit.
  
  
  METHODS
  Twenty-two patients after cardiac or major noncardiac surgery.
  
  
  METHODS
  After initial calibration of the pulse contour CO (PCO) method, CO was measured by PCO and by LiCO methods at 4, 8, 16, and 24 hrs. Recalibration of PCO was performed every 8 hrs. The systemic vascular resistance and dynamic response characteristics of the arterial catheter-transducer system were measured at each time point to determine whether these influenced the agreement between PCO and LiCO methods.
  
  
  RESULTS
  There was an excellent correlation between methods (r = .94). Bias was small (-0.005 L/min), and clinically acceptable limits of agreement were demonstrated between techniques. Although many catheter-transducer systems had poor dynamic response characteristics, this did not influence the level of agreement between the two techniques. An increase in systemic vascular resistance between two time points did tend to cause overestimation of LiCO by the PCO.
  
  
  CONCLUSIONS
  PCO measurement compared well with the lithium dilution method and can be considered an accurate technique for measuring beat-to-beat CO with limited risk to the patient.
authors.affiliation: Duke University Medical Center and Durham Veterans Affairs Medical Center, Durham, NC, USA.
authors.forename: James
authors.initials: J
authors.lastname: Pittman
authors.forename: Shahar
authors.initials: S
authors.lastname: Bar-Yosef
authors.forename: John
authors.initials: J
authors.lastname: SumPing
authors.forename: Matthew
authors.initials: M
authors.lastname: Sherwood
authors.forename: Jonathan
authors.initials: J
authors.lastname: Mark
mesh_terms: D002302:Cardiac Output / Q000502:physiology*; D002404:Catheterization; D006801:Humans; D007201:Indicator Dilution Techniques; D018021:Lithium Chloride; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000379:methods*; D011182:Postoperative Care; D011446:Prospective Studies; D011674:Pulse; D014159:Transducers; D014655:Vascular Resistance / Q000502:physiology
chemical_list: D018021:Lithium Chloride