Dynamic Hyperinflation During Maximal Voluntary Ventilation in Healthy Subjects

Not Applicable

• Conditions: Dynamic Hyperinflation
• Interventions: Behavioral: Healthy Subjects

• Registration Number: NCT02831465
• Lead Sponsor: Centre Hospitalier Universitaire Saint Pierre

Brief Summary

Maximal Voluntary Ventilation (MVV) correlates well with maximal exercise capacity and is used to assess the ventilatory function during exercise in COPD (Chronic Obstructive Pulmonary Disease) patients. Dynamic hyperinflation (DH) often occurs during MVV in COPD and is believed to be due to expiratory flow limitation.

The present study is intended to assess whether DH can also occur during MVV in normal subjects without expiratory flow limitation.

Detailed Description

Maximal voluntary ventilation (MVV) correlates well with maximal exercise capacity and is used to assess the ventilatory function during exercise in COPD (Chronic Obstructive Pulmonary Disease) patients. Dynamic hyperinflation (DH) often occurs during MVV in COPD and is believed to be due to expiratory flow limitation. The present study is intended to assess whether DH can also occur during MVV in normal subjects without expiratory flow limitation.

Study design: healthy subjects with normal lung function will perform MVV at increasing breathing frequencies and maximal tidal volume, from 10 to 100 cycles per minute. Inspiratory capacity (IC) will be measured at rest and after each 12 seconds of MVV in order to detect DH. From the moment DH appeares at a given frequency, only one additional MVV at a higher breathing frequency will be conducted to confirm DH.

Study Timeline

• Study Start: 2015-04
• Status Verified: 2016-07
• Study First Submitted: 2016-07-11
• Study First Submitted QC: 2016-07-12
• Study First Posted: 2016-07-13
• Last Update Submitted: 2017-02-01
• Last Update Posted: 2017-02-02
• Primary Completion: 2017-05
• Study Completion: 2017-06

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 45

Inclusion Criteria

• Healthy subjects

Exclusion Criteria

• History of asthma, obstructive syndrome on basic lung function

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
healthy subjects	Healthy Subjects	Subjects with normal lung function between 40 and 70 years old.

Primary Outcome Measures

Name	Time	Method
Frequency which induces Dynamic Hyperinflation	day one	We analyze Frequency of Maximal Voluntary Ventilation (MVV) which induces a significant decrease of the Inspiratory Capacity (IC) post MVV compared to the IC at rest.

Secondary Outcome Measures

Name	Time	Method
Correlation between the frequency which induces Dynamic Hyperinflation (DH) and Forced Vital Capacity	day one	We analyze if there is a good correlation between the frequency which induces a significant Dynamic Hyperinflation (DH) and Forced Vital Capacity
Correlation between the frequency which induces Dynamic Hyperinflation (DH) and IC/FVC ratio (IC : Inspiratory Capacity at rest ; FVC : Forced Vital Capacity)	day one	We analyze if there is a good correlation between the frequency which induces a significant Dynamic Hyperinflation (DH) and IC/FVC ratio (IC : Inspiratory Capacity at rest ; FVC : Forced Vital Capacity)
Correlation between the frequency which induces Dynamic Hyperinflation (DH) and Forced Expiratory Volume in one second	day one	We analyze if there is a good correlation between the frequency which induces a significant Dynamic Hyperinflation (DH) and Forced Expiratory Volume in one second
Correlation between the frequency which induces Dynamic Hyperinflation (DH) and body mass index	day one	We analyze if there is a good correlation between the frequency which induces a significant Dynamic Hyperinflation (DH) and body mass index
Correlation between the frequency which induces Dynamic Hyperinflation (DH) and age	day one	We analyze if there is a good correlation between the frequency which induces a significant Dynamic Hyperinflation (DH) and age
Correlation between the frequency which induces Dynamic Hyperinflation (DH) and Forced Expiratory Flows at 25%, 50% and 75% of Forced Vital Capacity	day one	We analyze if there is a good correlation between the frequency which induces a significant Dynamic Hyperinflation (DH) and Forced Expiratory Flows at 25%, 50% and 75% of Forced Vital Capacity
Comparison Maximal Voluntary Ventilation with Forced Expiratory Volume in one second multiplied by 35	day one	We compare Maximal Voluntary Ventilation at the different frequencies with the common predictive value of maximal ventilation obtained by multiplying Forced Expiratory Volume in one second by 35
Correlation between the frequency which induces Dynamic Hyperinflation (DH) and Inspiratory Capacity at rest	day one	We analyzed if there is a good correlation between the frequency which induces a significant Dynamic Hyperinflation (DH) and Inspiratory capacity at rest

Trial Locations

Locations (1)

CHU St. Pierre; 🇧🇪 Brussels, Brussels Capital Region, Belgium