Monitoring of cardiac output in cardiogenic shock and low-output heart failure: LiDCO vs pulmonary artery catheter thermodilution

Introduction

Determination and possibly monitoring of cardiac output (CO) is essential in cardiogenic shock (CS) and low-output heart failure (HF). The value of pulse contour analysis in these patients is unknown.

Hypothesis

The aim of the present study was to assess the feasibility of LiDCO-pulse contour analysis in patients with CS and HF and to compare LiDCO with the standard pulmonary artery catheter (PAC).

Methods

A total of 27 patients (17 male, age 62 ± 13 years, SAPS II 52 ± 19; mechanical ventilation n = 24; CS and HF, group 1, n = 14; control, group 2, n = 13) and a total of 72 measurements were included (a mean of 2.17 consecutive measurements/patient). The CO was measured using PAC and LiDCO simultaneously in all patients. The LiDCO was calibrated according to the manufacturer.

Results

CO-PAC and CO-LiDCO showed a significant correlation (r = 0.66, P = 0.001) for the group as a whole. The correlation was lower in group 1 (r = 0.45, P = 0.004) vs group 2 (r = 0.58, P = 0.001). There was good agreement between the two methods for the entire group (mean difference 0.086, 95% CI -0.29 to 0.47). Respective values were 0.08 (95% CI -0.37 to 0.54) for group 1 and 0.09 (95% CI -0.58 to 0.7) for group 2.

Conclusion

There was a somewhat lower correlation between CO-PAC and CO-LiDCO in patients with CS and HF when compared with controls. From a clinical standpoint, agreement between the two methods was fairly good.