title: A comparison of endotracheal bioimpedance cardiography and transpulmonary thermodilution in cardiac surgery patients.
abstract: OBJECTIVE
  The authors hypothesized that bioimpedance cardiography measured by the Endotracheal Cardiac Output Monitor (ECOM; ConMed, Utica, NY) is a convenient and reliable method for both cardiac index (CI) assessment and prediction in fluid responsiveness.
  
  
  METHODS
  A prospective observational study.
  
  
  METHODS
  A teaching university hospital.
  
  
  METHODS
  Twenty-five adult patients.
  
  
  METHODS
  Admission to the intensive care unit after conventional cardiac surgery and investigation before and after a fluid challenge.
  
  
  RESULTS
  Simultaneous comparative CI data points were collected from transpulmonary thermodilution (TD) and ECOM. Correlations were determined by linear regression. Bland-Altman analysis was used to compare the bias, precision, and limits of agreement. The percentage error was calculated. Pulse-pressure variations (PPVs) and stroke-volume variations (SVVs) before fluid challenge were collected to assess their discrimination in predicting fluid responsiveness. A weak but statistically significant relationship was found between CI(TD) and CI(ECOM) (r = 0.31, p = 0.03). Bias, precision, and limits of agreement between CI(TD) and CI(ECOM) were 0.08 L/min/m(2) (95% confidence interval, -0.11 to 0.27), 0.68 L/min/m(2), and -1.26 to 1.42 L/min/m(2), respectively. The percentage error was 51%. A nonsignificant positive relationship was found between percent changes in CI(TD) and CI(ECOM) after fluid challenge (r = 0.37, p = 0.06). Areas under the ROC curves for both PPV and SVV to predict fluid responsiveness were 0.86 (95% confidence interval, 0.67-1.06) and 0.89 (95% confidence interval, 0.74-1.04, respectively; p = 0.623).
  
  
  CONCLUSIONS
  Continuous measurements of CI under dynamic conditions are consistent and easy to obtain with ECOM although not interchangeable with transpulmonary thermodilution. SVV given by ECOM is a dynamic parameter that predicts fluid responsiveness with good accuracy and discrimination.
authors: Department of Anesthesiology and Critical Care Medicine, CHU de Caen, Caen, France. fellahi-jl@chu-caen.fr
authors: Jean-Luc
authors: JL
authors: Fellahi
authors: Marc-Olivier
authors: MO
authors: Fischer
authors: Olivier
authors: O
authors: Rebet
authors: Massimo
authors: M
authors: Massetti
authors: Jean-Louis
authors: JL
authors: Gérard
authors: Jean-Luc
authors: JL
authors: Hanouz
mesh_terms: D000368:Aged; D002302:Cardiac Output / Q000502:physiology*; D006348:Cardiac Surgical Procedures / Q000379:methods*; D002307:Cardiography, Impedance / Q000379:methods; D017097:Electric Impedance; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D013815:Thermodilution / Q000379:methods