Comparison of Three Noninvasive Ventilation Modes: a Physiological Study in Healthy Volunteers

Study Overview
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Brief Summary
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Noninvasive ventilation (NIV) is a well established, safe, and effective technique in improving gas exchange while reducing dyspnea and inspiratory effort in patients with either hypoxemic and hypercapnic acute respiratory failure (ARF) and averts the risk secondary to endotracheal intubation.Crucial factors for NIV success, in any forms of respiratory failure, are the tolerance to the interface used and the ability of the interface to unload inspiratory-muscle. Helmet is better tolerated over time, allowing continuous application of NIV for longer periods, while face mask has been proved to be more efficient at iso-support in unloading the respiratory muscles and improving patient-ventilator synchrony. Helmet NEXT (CaStar, NIV model, Starmed, Mirandola, Italy) is a novel type of helmet with a better compliant wall, that avoid the use of armpit braces potentially improving, compared to the standard helmet, both pressurization and patient-ventilator interaction and tolerance. The objective of this study is to compare the effects of NIV delivered via face mask, standard helmet, and NEXT helmet in terms of work of breathing, patient-ventilator interaction, and comfort.

Detailed Description
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16 Healthy volunteers will be enrolled. They will be ventilated with non invasive ventilation. The Work of breathing, ventilator/patient asynchrony, and ventilatory comfort produced between face mask, Helmet and NEXT helmet will be compared.

Official Title
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Comparison of Helmet NEXT, Helmet Standard and Facemask for Noninvasive Ventilation: a Physiological Study in Healthy Volunteers

Conditions
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Respiratory Failure, Non Invasive Ventilation on Healthy Volunteer

Intervention / Treatment
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* Device: Non invasive ventilation HELMET
* Device: Non invasive ventilation facemask (Respironics)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy volunteers Exclusion Criteria: contraindications for nasogastric tube placement Respiratory disease Pregnancy No French health insurance

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 60 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Supportive Care
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: HELMET<br>The HELMET and HELMET NEXT modes will be tested by each patient. | Device: Non invasive ventilation HELMET<br>* The HELMET and HELMET NEXT modes will be tested by each patient.<br>|
| Sham Comparator: Facemask<br>The facemask will be used by each patient. | Device: Non invasive ventilation facemask (Respironics)<br>* The facemask Respironics (Herrsching, Germany) will be used by each patient.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Work of breathing | To estimate the work of breathing, we will determine the swings in transdiaphragmatic pressure (Pdi) and the transdiaphragmatic pressure-time product (PTPdi) | during the single visit study (day 1) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Ventilatory comfort | The comfort will be assessed by a self-assessment of the patient on a visual analog scale between 0 (excellent) and 10 (discomfort). | during the single visit study (day 1) | 
| Patient-ventilator asynchronies | The patient-ventilator asynchronies will be assessed by the asynchronie index (number of asynchronies / number of respiratory cycles). The number of asynchronies will be assessed by the investigator, on the records of the pression curves and the respiratory outputs. | during the single visit study (day 1) | 
| Ventilatory parameters | The respiratory frequency and current volume will be measured. | during the single visit study (day 1) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Non invasive ventilation, Helmet, NEXT Helmet, Work of breathing, Intensive care