Estimation of Cardiac Output by Noninvasive Echocardiographic Techniques in the Critically Ill Subject

18 critically ill patients (19 studies) in a general intensive care unit requiring pulmonary artery catheterization, with diagnoses including pulmonary embolus, cardiogenic shock, septic shock, Legionnaire's disease, and perioperative myocardial infarction.

Transthoracic echocardiographic techniques for cardiac output estimation (two-chamber Simpson's, four-chamber Simpson's, and left ventricular outflow tract [LVOT] Doppler methods).

Thermodilution technique via pulmonary artery catheterization.

Accuracy and agreement of cardiac output estimation (measured via correlation coefficient and Bland-Altman limits of agreement).surrogate