title: Comparison of the endotracheal cardiac output monitor to thermodilution in cardiac surgery patients.
abstract: OBJECTIVE
  To compare cardiac output (CO) measurements from a novel endotracheal bioimpedance cardiac output monitor device (ECOM; ConMed, Irvine, CA) to simultaneous pulmonary artery thermodilution (TD) CO.
  
  
  METHODS
  Prospective study.
  
  
  METHODS
  One academic hospital.
  
  
  METHODS
  Forty volunteer patients undergoing cardiac surgery.
  
  
  METHODS
  Intraoperative CO measurements.
  
  
  RESULTS
  Simultaneous comparative data points were collected from ECOM and TD at 4 periods: post-induction, post-sternotomy, post-cardiopulmonary bypass, and post-chest closure. The mean CO(TD) was compared with CO(ECOM) for each operative period then assessed for agreement by linear regression, Bland-Altman analysis, and percent error methods. There were 35 men (87.5%) with a mean age of 66 ± 10.7 years in the present study population. R values (p value) for the 4 time periods were 0.50 (0.002), 0.33 (0.035), 0.42 (0.007), and 0.48 (0.002). Bias and 95% limits of agreement in L/min were -0.11 (-2.40 to 2.18), 0.04 (-2.57 to 2.65), -0.06 (-2.86 to 2.74), and 0.02 (-2.42 to 2.45). Percent errors of the 4 time periods were 51%, 53%, 50%, and 48%.
  
  
  CONCLUSIONS
  ECOM did not adequately agree with TD in patients undergoing cardiac surgery.
authors.affiliation: Division of Cardiothoracic Anesthesiology, The Texas A&M University System Health Sciences Center College of Medicine, Scott & White Memorial Hospital, Temple, TX 76508, USA. tball@swmail.sw.org
authors.forename: Timothy R
authors.initials: TR
authors.lastname: Ball
authors.forename: Benjamin C
authors.initials: BC
authors.lastname: Culp
authors.forename: Vivekkumar
authors.initials: V
authors.lastname: Patel
authors.forename: David F
authors.initials: DF
authors.lastname: Gloyna
authors.forename: David P
authors.initials: DP
authors.lastname: Ciceri
authors.forename: William C
authors.initials: WC
authors.lastname: Culp
mesh_terms: D000368:Aged; D002302:Cardiac Output / Q000502:physiology*; D006348:Cardiac Surgical Procedures / Q000379:methods*; D005260:Female; D006801:Humans; D007442:Intubation, Intratracheal / Q000379:methods*; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods*; D011446:Prospective Studies; D013815:Thermodilution / Q000379:methods