Skip to main content

Mini-fluid challenge: how much fluid and what parameter to use?

Introduction

The mini-fluid challenge is a widely used strategy to manage fluid loading in the ICU and OR. Although it might be a rational strategy, data on the mini-fluid challenge and its reliability are very limited. We investigated the value of changes in pulse contour cardiac output as a result of a mini-fluid challenge of 50 and 100 ml to predict fluid loading responsiveness.

Methods

We measured the effects after the administration of 50, 100 and 500 ml bolus colloid infusions on CO (Modelflow (COm) and LiDCO (COli)), CVP and MAP in 21 patients on mechanical ventilation after elective cardiothoracic surgery. From the data we analysed the smallest volume that was predictive for the effects of 500 ml on cardiac output.

Results

COli and COm increased after 50, 100 and 500 ml fluid loading. Best results are observed for changes in COm after 100 ml fluid loading (area under the ROC 0.86, 95% CI between 0.65 and 1.00). A change in Modelflow CO of at least 4.3% has a sensitivity of 67% and a specificity of 100% after 100 ml fluid loading. Sensitivity is 60% and specificity 83% for a similar cutoff in CO measured with the LiDCO device after 100 ml fluid loading. In our patient population, MAP and COli did not predict responsiveness with more accuracy than mathematical chance. See Figure 1.

Conclusion

Changes in pulse contour CO can be used in a mini-fluid challenge to assess fluid responsiveness in our postcardiac surgery patients.

Author information

Affiliations

Authors

Corresponding author

Correspondence to B Geerts.

Rights and permissions

This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data.

Reprints and Permissions

About this article

Cite this article

Geerts, B., De Wilde, R., Maas, J. et al. Mini-fluid challenge: how much fluid and what parameter to use?. Crit Care 17, P204 (2013). https://doi.org/10.1186/cc12142

Download citation

Keywords

  • Patient Population
  • Cardiac Output
  • Mechanical Ventilation
  • Emergency Medicine
  • Small Volume