Reliability of Cardiac Output Measurements Using LiDCOrapid and Calibration by Transesophageal Echocardiography With the Continuous Pulmonary Artery Thermodilution Method in Patients Undergoing Aortic Valve Replacement for Aortic Stenosis

Abstract

This study investigated the accuracy of arterial waveform analysis estimations of cardiac output (COAW) and the efficacy of calibrations involving transesophageal echocardiography with continuous cardiac output values obtained using a pulmonary artery catheter. Prospective cohort study. University hospital operating room. Twelve patients undergoing aortic valve replacement for aortic stenosis. A pulmonary artery catheter was placed in each patient, and continuous cardiac output was determined using thermodilution principles. LiDCOrapid and transesophageal echocardiography were used to measure COAW and to perform the calibration, respectively. Simultaneous recording of continuous cardiac output and COAW values were performed every 20 minutes, after inducing anesthesia. COAW was calibrated using transesophageal echocardiography (COAW-cal) before and after initiating cardiopulmonary bypass (CPB); the COAW and COAW-cal were recorded concurrently using a LiDCOrapid monitor. For the pre-CPB dataset (34 data pairs), the mean bias and percentage error were, respectively, 0.10 L/min and 34% for COAW versus continuous cardiac output and -0.098 L/min and 27% for COAW-cal versus continuous cardiac output. Similarly, for the post-CPB (45 data pairs), the mean bias and percentage error were, respectively, 0.75 L/min and 34% for COAW and 0.059 L/min and 26% for COAW-cal. A 4-quadrant plot demonstrated an acceptable pre-CPB concordance rate of 93.3% for COAW and 93.8% for COAW-cal. COAW measurements, using LiDCOrapid, have acceptable trending ability pre-CPB. The determination of cardiac output variations, using transesophageal echocardiography, is useful for managing patients undergoing aortic valve replacement for aortic stenosis.