Journal of the American College of Cardiology
-
J. Am. Coll. Cardiol. · May 1989
Comparative StudyInstantaneous and continuous cardiac output obtained with a Doppler pulmonary artery catheter.
A newly developed, flow-directed, Doppler pulmonary artery catheter, capable of measuring instantaneous and continuous cardiac output, was evaluated in both an in vitro pump model and an animal model. Quantitative flow was calculated with use of the instantaneous, space-average velocity (obtained from the velocity profile) and the instantaneous area (obtained from the vessel diameter) and compared with electromagnetic flow. Additionally, simultaneous thermodilution flow measurements were obtained. ⋯ However, Doppler determinations of flow remained more accurate than did simultaneous thermodilution measurements (r2 = 0.73, m = 0.79, SEE = 0.72). Accurate, continuous and instantaneous cardiac output measurements appear possible with use of a flow-directed, Doppler pulmonary artery catheter. This catheter system also provides instantaneous diameter measurements and mapping of instantaneous velocity profiles within the main pulmonary artery and may lead to more accurate Doppler-derived assessment of cardiac output in humans.