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Updated: Nov 6, 2025

Continuous Venous-Arterial Doppler Ultrasound During a Preload Challenge
Published on: January 20, 2023
Assessing volume responsiveness using right ventricular dynamic indicators of preload
Michael F Graessler1, Karin H Wodack2, Hans O Pinnschmidt3
1Department of Anesthesiology, Centre for Anesthesiology and Intensive Care Medicine, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany. m.graessler@uke.de.
Purpose:
Dynamic indicators of preload currently only do reflect preload requirements of the left ventricle. To date, no dynamic indicators of right ventricular preload have been established. The aim of this study was to calculate dynamic indicators of right ventricular preload and assess their ability to predict ventricular volume responsiveness.
Materials And Methods:
The study was designed as experimental trial in 20 anaesthetized pigs. Micro-tip catheters and ultrasonic flow probes were used as experimental reference to enable measurement of right ventricular stroke volume and pulse pressure. Hypovolemia was induced (withdrawal of blood 20 ml/kg) and thereafter three volume-loading steps were performed. ROC analysis was performed to assess the ability of dynamic right ventricular parameters to predict volume response.
Results:
ROC analysis revealed an area under the curve (AUC) of 0.82 (CI 95% 0.73-0.89; p < 0.001) for right ventricular stroke volume variation (SVVRV), an AUC of 0.72 (CI 95% 0.53-0.85; p = 0.02) for pulmonary artery pulse pressure variation (PPVPA) and an AUC of 0.66 (CI 95% 0.51-0.79; p = 0.04) for pulmonary artery systolic pressure variation (SPVPA).
Conclusions:
In our experimental animal setting, calculating dynamic indicators of right ventricular preload is possible and appears promising in predicting volume responsiveness.
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