Fluid-responsiveness in Children Ventilated With LOW Tidal Volume - The FLOW Study.

NCT07494643 | Recruiting

• 1 other identifier: CHUBX 2025/059
• Study Type: interventional
• Target: 60
• Locations: 1 country
• Sites: 6

Brief Summary

In this study of diagnostic accuracy, the investigators aim to validate a fluid-responsiveness test in critically ill children mechanically ventilated with low tidal volume. This test is the famous respiratory variability of peak aortic velocity (ΔVPeak), which is based on cardiopulmonary interactions but is only validated in mechanically ventilated children with a tidal volume of at least 8ml/kg, which is uncommon nowadays. This would help physicians to identify children ventilated with low tidal volume and suffering from acute circulatory failure that could benefit from a volume expansion, thus avoiding a potentially useless or even dangerous fluid expansion that could lead to fluid overload. To this end, the diagnostic accuracy of ΔVPeak to predict fluid responsiveness (define as a 15% increase in echocardiographically measured SV after volume expansion) will be measured in mechanically ventilated children with low tidal volume and requiring fluid bolus.

Conditions

Circulatory Failure (Shock)

Keywords

echocardiography; fluid responsiveness; goal-directed fluid management; shock; volume expansion

Outcome Measures

Primary Outcomes (1)

• Area under the ROC curve (AUROC, %) of ΔVPeak to diagnose fluid responsiveness

  The primary outcome measure of a diagnostic accuracy study is the discriminative ability of an index test (expressed as an area under the ROC curve) to diagnose a condition (defined by a positive gold-standard reference test). In this study: * The index test is ΔVPeak at baseline = difference between maximal and minimal peak aortic velocity (m/s) during 5 cardiac cycles, divided by mean peak aortic velocity (m/s). Peak aortic velocity is measured by transthoracic echocardiography with pulsed-Doppler in the left ventricular outflow tract from an apical 5-chambers view. * The condition is "fluid responsiveness" * The gold-standard reference test to diagnose fluid responsiveness is a stroke volume (SV) increase of at least 15% between baseline and after volume expansion: ΔSV-VE \> 15% = ((SV after volume expansion - SV at baseline) / SV at baseline) \> 15%. SV (ml) will be measured by transthoracic echocardiography as the product of left ventricular outflow tract surface (cm², from a par

  Baseline

Secondary Outcomes (21)

• AUROC (%) of the following index test to diagnose fluid responsiveness

  Baseline

• Influencing factors

  Baseline

• Poor respiratory tolerance

  Baseline , immediately after volume expansion

• Proportion of patients in each age category, according to fluid responsiveness

  Baseline

• Sex, in patients with and without fluid responsiveness

  Baseline

Study Arms (1)

Diagnostic accuracy of ΔVPeak

EXPERIMENTAL

Procedure: Echocardiographic

Interventions

Echocardiographic PROCEDURE

Patients included in this study would have received volume expansion anyway, as the prescription of 10ml/kg volume expansion by the physician in charge is the main inclusion criterion. The purpose of this study is to evaluate the diagnostic accuracy of a fluid responsiveness test. To this end, patients will undergo echocardiographic assessments, which are non-invasive, non-radiative, well tolerated and commonly used in this population as a standard of care in our center. No additional blood test or invasive parameters will be collected be collected.

Diagnostic accuracy of ΔVPeak

Eligibility Criteria

• Age: 0 Days - 15 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17)

You may qualify if:

• Age between 0 days and 15 years old
• Patient hospitalized in a pediatric intensive care unit.
• Prescription of a 10ml/kg (±20%) fluid expansion by the physician in charge, as a standard care treatment of circulatory failure (precise indication is up to the physician in charge).
• Mechanical ventilation
• Tidal volume \< 6ml/kg (±15%)
• Fluid responsiveness echocardiographic assessment as of routine care

You may not qualify if:

• Prematurity (corrected gestational age bellow 37 weeks)
• Arythmia
• Hemodynamic instability making dangerous the delay necessary for any measurement.
• Prone position
• Impairment of echocardiographic acoustic window
• Extracorporeal membrane oxygenation
• Respiratory rate (measured) \> 60 cycles per minute (including high frequency oscillation)
• Significant breathing movements (high work of breathing, clinically assessed)
• Restlessness with desynchronization patient/ventilator
• Open chest
• Cardiogenic pulmonary oedema
• Known intracardiac or vascular shunt
• Known hemodynamically significant valvopathy
• Opposition to participate expressed by the patient or by a parent or legal guardian

Sponsors & Collaborators

• University Hospital, Bordeaux: lead

Study Sites (6)

CHU d'Amiens Picardie

Amiens, France

RECRUITING

CHU de BORDEAUX

Bordeaux, France

RECRUITING

CHU de LIMOGES

Limoges, France

RECRUITING

Hôpital Necker-Enfants Malades

Paris, France

RECRUITING

Hôpital Robert Debré

Paris, France

RECRUITING

CHU de Rouen Normandie

Rouen, France

RECRUITING

MeSH Terms

Conditions

Shock

Condition Hierarchy (Ancestors)

Pathologic Processes; Pathological Conditions, Signs and Symptoms

Central Study Contacts

Julien GOTCHAC, MD

CONTACT

0556795913; julien.gotchac@chu-bordeaux.fr

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: February 2, 2026
• First Posted: March 27, 2026
• Study Start: November 10, 2025
• Primary Completion (Estimated): November 1, 2027
• Study Completion (Estimated): November 1, 2027
• Last Updated: March 27, 2026

Record last verified: 2026-03

Locations

FR (6)