COMPARISON OF METHODS OF CARDIAC-OUTPUT MEASUREMENTS DETERMINED BY DYE DILUTION, PULSED DOPPLER-ECHOCARDIOGRAPHY AND THERMODILUTION IN HORSES

Cardiac output (CO) measurements by the three methods of dye dilution, pulsed Doppler echocardiography and thermodilution in horses under an esthetized conditions were compared. Although CO determined by the the rmodilution method was slightly higher than those obtained by the othe r two methods, the measurements by all methods showed almost similar r esults. The coefficients of correlation between the dye dilution and t hermodilution methods, the dye dilution and pulsed Doppler echocardiog raphy methods, and the thermodilution and pulsed Doppler echocardiogra phy methods were 0.87, 0.89, and 0.88, respectively (P<0.01). These re sults indicate that pulsed Doppler echocardiography and thermodilution methods could be no less useful than the traditional dye dilution met hod for evaluating of CO in horses. The pulsed Doppler echocardiograph y method may offer some advantage over other two methods; it is non-in vasive and enables continuous measurement of CO.