Hemodynamic Measurements After Cardiac Surgery: Transesophageal Doppler Versus Pulmonary Artery Catheter

Objective: The purpose of this study was to compare hemodynamic data derived from the transesophageal Doppler monitor (Medicina TECO, Berkshire, United Kingdom) against those obtained from a pulmonary artery catheter after coronary artery bypass grafting (CABG). Design: Prospective, nonrandomized, clinical study. Setting: Single, tertiary referral center. Participants: Thirty-five adult patients. Interventions: Cardiac output and hemodynamic variables were measured and compared at 4 predefined time points in patients undergoing elective off-pump CABG surgery from January 2003 through June 2003. Measurement and Main Results: A total of 140 pairs for cardiac output (CO) data were obtained. Transesophageal cardiac output (TECO) values ranged from 1.9 to 8.7 L/min. Thermodilution cardiac output (TDCO) values ranged from 2.7 to 7.6 L/min. Matched measurements were made with each patient at intervals of 30 minutes. Bland-Altman analysis revealed a mean bias of 1.18 ± 1.36 L/min, with a correlation (r) of 0.593 (p < 0.000) between TECO and TDCO. Similarly poor correlation was observed among cardiac index (r = 0.523), stroke volume (r = 0.615), systemic vascular resistance (r = 0.595), left ventricular stroke work index (r = 0.594), and right ventricular stroke work index (r = 0.590) measured by an esophageal Doppler monitor against a pulmonary artery catheter. Conclusion: A transesophageal Doppler device (Medicina TECO) cannot be relied on as a sole method for monitoring cardiac output and derived hemodynamic variables in patients after CABG surgery.