Research

Assessment of stroke volume variation for prediction of fluid responsiveness using the modified FloTrac™ and PiCCOplus™ system

Christoph K Hofer¹ , Alban Senn² , Luc Weibel¹ and Andreas Zollinger¹

¹Institute of Anaesthesiology and Intensive Care Medicine, Triemli City Hospital, Birmensdorferstrasse, CH-8063 Zurich, Switzerland

²Department of Internal Medicine, Triemli City Hospital, Birmensdorferstrasse, CH-8063 Zurich, Switzerland

author email corresponding author email

Critical Care 2008, 12:R82doi:10.1186/cc6933

Published:	20 June 2008

Abstract

Introduction

Stroke volume variation (SVV) has repeatedly been shown to be a reliable predictor of fluid responsiveness. Various devices allow automated clinical assessment of SVV. The aim of the present study was to compare prediction of fluid responsiveness using SVV, as determined by the FloTrac™/Vigileo™ system and the PiCCOplus™ system.

Methods

In patients who had undergone elective cardiac surgery, SVV_FloTrac was determined via radial FloTrac sensor, and SVV_PiCCO and pulse pressure variation were assessed via a femoral PiCCO catheter. Stroke volume was assessed by transpulmonary thermodilution. All variables were recorded before and after a volume shift induced by a change in body positioning (from 30° head-up position to 30° head-down position). Pearson correlation, t-test, and Bland-Altman analysis were performed. Area under the curve was determined by plotting receiver operating characteristic curves for changes in stroke volume in excess of 25%. P < 0.05 was considered statistically significant.

Results

Body positioning resulted in a significant increase in stroke volume; SVV_FloTrac and SVV_PiCCO decreased significantly. Correlations of SVV_FloTrac and SVV_PiCCO with change in stroke volume were similar. There was no significant difference between the areas under the curve for SVV_FloTrac and SVV_PiCCO; the optimal threshold values given by the receiver operating characteristic curves were 9.6% for SVV_FloTrac (sensitivity 91% and specificity 83%) and 12.1% for SVV_PiCCO (sensitivity 87% and specificity 76%). There was a clinically acceptable agreement and strong correlation between SVV_FloTrac and SVV_PiCCO.

Conclusion

SVVs assessed using the FloTrac™/Vigileo™ and the PiCCOplus™ systems exhibited similar performances in terms of predicting fluid responsiveness. In comparison with SVV_PiCCO, SVV_FloTrac has a lower threshold value.