Related Experiment Video
Updated: Aug 9, 2026
Bedside Ultrasound for Guiding Fluid Removal in Patients with Pulmonary Edema: The Reverse-FALLS Protocol
Published on: July 28, 2018
Does Respiratory Variation in Inferior Vena Cava Diameter Predict Fluid Responsiveness: A Systematic Review and
Elliot Long1, Ed Oakley, Trevor Duke
1*Department of Emergency Medicine, The Royal Children's Hospital, Parkville, Victoria, Australia†Murdoch Childrens Research Institute, Parkville, Victoria, Australia‡Department of Paediatrics, Faculty of Medicine, Dentistry, and Health Sciences, University of Melbourne, Melbourne, Victoria, Australia§Paediatric Intensive Care Unit, The Royal Children's Hospital, Parkville, Victoria, Australia.
Background:
The aim of fluid resuscitation is to increase stroke volume, yet this effect is observed in only 50% of patients. Prediction of fluid responsiveness may allow fluid resuscitation to be administered to those most likely to benefit. The aim of this study was to systematically review the test characteristics of respiratory variation in inferior vena cava (IVC) diameter as a predictor of fluid responsiveness in patients with acute circulatory failure.
Methods:
Electronic searches combined with reference review of identified studies. Prospective observational studies of all patient groups and ages that used a recognized reference standard, stratified participants into fluid responders and fluid non-responders, and used summary statistics to describe their results were selected for inclusion. Study design, size, setting, patient population, use of mechanical ventilation and tidal volume, definition of fluid responsiveness, fluid challenge strategy, and summary statistics were abstracted. Quality assessment was performed using the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) domains.
Results:
Seventeen studies involving 533 patients were included, in whom 253 (47%) were fluid responders. The pooled sensitivity and specificity for a positive IVC ultrasound as a predictor of fluid responsiveness were 0.63 (95% confidence interval [CI]: 0.56-0.69) and 0.73 (95% CI: 0.67-0.78), respectively, with a pooled area under the receiver operating characteristic curve of 0.79 (standard error 0.05). In subgroup analysis, respiratory variation in IVC diameter was a better predictor of fluid responsiveness in mechanically ventilated patients.
Conclusions:
Respiratory variation in IVC diameter has limited ability to predict fluid responsiveness, particularly in spontaneously ventilating patients. A negative test cannot be used to rule out fluid responsiveness. Clinical context should be taken into account when using IVC ultrasound to help make treatment decisions.
Related Concept Videos
01:20Assessment of Ventilation I: Respiratory Rate
A Ventilation assessment is critical for monitoring a patient's health status. Respiration, one of the most accessible vital signs, provides insights into the function of numerous body systems and can indicate serious health issues, such as brainstem injuries from head trauma.
Critical Guidelines for Assessing Ventilation:
01:15Respiratory Volumes
Tidal Volume (TV) Tidal volume (TV) is the air inhaled or exhaled in a...
01:29Assessment of Ventilation II: Respiratory Depth and Rhythm
Respiratory depth measures the volume of air inhaled or exhaled during a breath. It can vary from shallow to deep and typically remains consistent when a person is at rest or asleep. Occasionally, individuals will automatically inhale deeply, known as sighing, which inflates the lungs with more air than normal breathing.
To assess respiratory depth, observe the degree of chest excursion or movement:
01:20Vascular Resistance
The primary determinants of vascular resistance are vessel diameter, blood viscosity, and vessel length. Among these, vessel diameter plays the most significant role due to the fourth power relationship described by...
01:19Factors Affecting Pulmonary Ventilation
Alveolar Surface Tension
The alveolar fluid lines the luminal surface of the alveoli and exerts a force called surface tension. This force is caused by the polar water molecules in the liquid being more strongly attracted to each...
01:22Respiratory Volumes and Capacities