Expiratory Flow Limitation Assessment

NCT03462849 | Completed

• 2 other identifiers: 69HCL17_05952017-A02557-46
• Study Type: interventional
• Target: 25
• Locations: 1 country
• Sites: 2

Brief Summary

This study intended to assess the expiratory flow limitation (EFL) during tidal breath in patients intubated in intensive care unit (ICU) for moderate or severe acute respiratory distress syndrome (ARDS). EFL is defined as the lack of increase in expiratory flow in response to an increase in alveolar-to-atmospheric pressure gradient. It reflects airway closure. Early studies have been done using the Negative expiratory pressure (NEP) technique, which is no longer available. We proposed in present study a new method, which consists of diverting manually the expiratory flow to the atmosphere by-passing the expiratory valve. We aimed at assessing EFL at positive expiratory pressure (PEP) 5 cmH2O in semi-recumbent then in supine position together with measurement of trans-pulmonary pressure and regional lung ventilation. Higher PEP levels will be tested, namely 10, 15 and a trans-pulmonary PEP of 3 cmH2O, in semi-recumbent position.

Conditions

Acute Respiratory Distress Syndrome

Keywords

ARDS; expiratory flow limitation; trans-pulmonary pressure; airway closure

Outcome Measures

Primary Outcomes (1)

• EFL at PEP 5 cmH2O

  A Fleish 2 pneumotachograph and a port to measure airway pressure are attached at the Y piece of the ventilator circuit and connected to a Biopac 150. At the end of inspiration the air is expelled to the atmosphere upstream the expiratory valve. The flow volume loop at baseline and that during the manoeuver are plotted and patients classified as EFL or not EFL (NFL). Measurements are taken in semi-recumbent then after 5 minutes in supine position.

  at inclusion

Secondary Outcomes (16)

• Trans-pulmonary pressure at end expiratory at PEP 5

  at inclusion

• Trans-pulmonary pressure at end expiratory at PEP 10 in EFL and NFL patients

  15 minutes after PEP set to 10 cm H2O

• Lung compliance at PEP 10 in EFL and NFL patients

  15 minutes after PEP set to 10 cm H2O

• lung ventilation distribution at PEP 10 in EFL and NFL patients

  15 minutes after PEP set to 10 cm H2O

• Transcutaneous oxygen saturation (SpO2) at PEP 10 in EFL and NFL patients

  15 minutes after PEP set to 10 cm H2O

Study Arms (2)

Patients with EFL at PEP 5

OTHER

Patients with EFL at PEP 5 at the time of inclusion either in supine or semi-recumbent position

Other: increase in positive end expiratory pressure

Patients with no EFL at PEP 5

OTHER

Patients with no EFL at PEP 5 at the time of inclusion in both supine and semi-recumbent positions

Other: increase in positive end expiratory pressure

Interventions

increase in positive end expiratory pressure OTHER

increase in positive end expiratory pressure from 5 to 10 then 15 cmH2O then at the value for trans pulmonary end expiratory pressure amounting to 3 cmH2O

Patients with EFL at PEP 5; Patients with no EFL at PEP 5

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• years or more in age
• moderate to severe ARDS according to the Berlin definition : Intubated (or tracheotomized) and mechanically ventilated in the ICU
• no pregnancy
• informed consent from the next of kin

You may not qualify if:

• Contra-indication to PEP \> 5 cmH2O
• extracorporeal membrane oxygenation (ECMO)
• chest tube
• mean arterial pressure \< 65 mmHg
• Contra-indication to oesophageal device
• underlying disease fatal in less than one year
• active therapy limitation
• under guardian
• refusal to participate
• not affiliated to insurance regimen
• speaking barrier of the next of kin
• investigator not available

Sponsors & Collaborators

• Hospices Civils de Lyon: lead

Study Sites (2)

CHU Grenoble Alpes

Grenoble, France

Location

Hôpital de la Croix Rousse

Lyon, 69004, France

Location

Related Publications (1)

• Guerin C, Terzi N, Galerneau LM, Mezidi M, Yonis H, Baboi L, Kreitmann L, Turbil E, Cour M, Argaud L, Louis B. Lung and chest wall mechanics in patients with acute respiratory distress syndrome, expiratory flow limitation, and airway closure. J Appl Physiol (1985). 2020 Jun 1;128(6):1594-1603. doi: 10.1152/japplphysiol.00059.2020. Epub 2020 Apr 30.

  PMID: 32352339 RESULT

MeSH Terms

Conditions

Respiratory Distress Syndrome

Interventions

Positive-Pressure Respiration

Condition Hierarchy (Ancestors)

Lung Diseases; Respiratory Tract Diseases; Respiration Disorders

Intervention Hierarchy (Ancestors)

Respiration, Artificial; Airway Management; Therapeutics; Respiratory Therapy

Study Officials

• Claude Guerin, Pr

  Hospices Civils de Lyon

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: DIAGNOSTIC
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: March 6, 2018
• First Posted: March 13, 2018
• Study Start: February 5, 2018
• Primary Completion: May 2, 2019
• Study Completion: May 2, 2019
• Last Updated: December 5, 2025

Record last verified: 2025-11

Locations

FR (2)