title: Simultaneous measurement of cardiac output by thermodilution, thoracic electrical bioimpedance and Doppler ultrasound.
abstract: To evaluate the accuracy of two non-invasive techniques for cardiac output (CO) measurement, we have measured CO simultaneously by thoracic electrical bioimpedance (TEB), pulsed Doppler ultrasound (DU) and standard thermodilution methods (TD) under different clinical conditions. Measurements were made in 10 patients: (I) during steady state anaesthesia with controlled IPPV ventilation (n = 131), spread over the entire ventilatory cycle; (II) during apnoea (n = 56); (III) during spontaneous breathing (n = 152) in the intensive care unit. Mean (SD) cardiac output values were: (I) COTD 3.5 (1.0) litre min-1, COTEB 3.4 (0.7) litre min-1, CODU 2.8 (0.7) litre min-1; (II) COTD 3.6 (0.6) litre min-1, COTEB 3.5 (0.4) litre min-1, CODU 2.9 (0.7) litre min-1; (III) COTD 7.7 (1.5) litre min-1, COTEB 7.6 (1.9) litre min-1, CODU 5.2 (1.4) litre min-1. The mean percentage deviation of TEB from TD ranged from -2.2% to 1.4% and that of DU from TD was from -16% to -32%. There were no statistically significant differences between TD and TEB, but TD and DU differed significantly during IPPV, apnoea and spontaneous ventilation (P < 0.0001).
authors.affiliation: Department of Anaesthesiology, University of Saarland, Homburg, Germany.
authors.forename: G
authors.initials: G
authors.lastname: Castor
authors.forename: R K
authors.initials: RK
authors.lastname: Klocke
authors.forename: M
authors.initials: M
authors.lastname: Stoll
authors.forename: J
authors.initials: J
authors.lastname: Helms
authors.forename: I
authors.initials: I
authors.lastname: Niedermark
mesh_terms: D000328:Adult; D000368:Aged; D001049:Apnea / Q000503:physiopathology; D002302:Cardiac Output / Q000502:physiology*; D017097:Electric Impedance; D005260:Female; D006801:Humans; D007385:Intermittent Positive-Pressure Ventilation; D008297:Male; D008875:Middle Aged; D013815:Thermodilution; D014463:Ultrasonography