Stroke volume index assessment using two minimal invasive devices during hemodynamic postoperative optimization

Introduction

Postoperative hemodynamic optimization has been proved to reduce morbidity in high-risk patients [1]. Nowadays stroke volume index (SVI) monitoring is available with different less invasive techniques that have shown different levels of agreement and precision with the pulmonary artery catheter [2]. The aim of this study was to evaluate agreement and precision between SVI obtained with a calibrated (LiDCO™plus; LiDCO Ltd, Cambridge, UK) and an uncalibrated pulse contour analysis device (FloTrac/Vigileo; Edwards Lifesciences, Irvine, CA, USA), in patients undergoing postoperative hemodynamic optimization.

Methods

Patients undergoing a hemodynamic optimization protocolized care according to a previous published trial [1] to reach an oxygen delivery index >600 ml/minute/m² after abdominal surgery were enrolled. After calibration of the LiDCO™plus, SVI data obtained from LiDCO™plus, and FloTrac/Vigileo (version 1.07) were recorded every 15 minutes for 6 hours. Agreement and precision between SVI obtained with LiDCO (SVI_LI) and SVI obtained with Vigileo (SVI_FT) were evaluated with Bland and Altman analysis.

Results

Thirteen patients (nine males, four females), mean age 68.5 (± 28.3) years were enrolled into the study. Two hundred and seventy SVI data pairs were analyzed. Bias was 1.79 ml/m², with a precision (1.96SD of the bias) of 25.1 ml/m² (Figure 1).

Figure 1

Bland and Altman analysis.

Conclusions

SVI obtained from the uncalibrated low-invasive, pulse contour analysis technique seems as accurate as the calibrated technique in a clinical hemodynamic protocolized setting to increase oxygen delivery in postoperative high-risk patients.