Comparison of the Endotracheal Cardiac Output Monitor to Thermodilution in Cardiac Surgery Patients

Objectives: 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 Design: Prospective study. Setting. One academic hospital. Participants: Forty volunteer patients undergoing cardiac surgery Interventions: Intraoperative CO measurements Measurements and Main 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 COE(COM) 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. (C) 2010 Elsevier Inc. All rights reserved.