Normalizing CO2 in Chronic Hyperventilation by a Novel Breathing Mask: A Pilot Study

Study Overview
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Brief Summary
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Background: Chronic Idiopathic Hyperventilation (CIH) is a form of dysfunctional breathing which has proven hard to treat effectively. The investigators hypothesised that by periodically inducing normocapnia over several weeks, it would be possible to raise the normal resting level/set point of CO2 and achieve a reduction of symptoms. Methods: Six CIH patients were treated two hours a day for four weeks with a novel breathing mask. The mask was used to induce normocapnia in these chronically hypocapnic patients. Capillary blood gases (PcCO2, pH, Standard Base Excess (SBE) etc.) were measured at baseline and once each week at least three hours after mask use, as well as spirometric values, breath holding tolerance and hyperventilation symptoms as per the Nijmegen Questionnaire (NQ),.

Official Title
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CO2 Rebreathing by a Partial Rebreathing Mask as a Treatment of Chronic Idiopathic Hyperventilation - a Pilot Study

Conditions
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Hyperventilation, Chronic Idiopathic Hyperventilation, Dysfunctional Breathing, Respiratory Alkalosis

Intervention / Treatment
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* Device: Partial Rebreathing Mask


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Chronic idiopathic hyperventilation, i.e.: PCO2 level below 4.7 kPa AND SBE value more negative than -1.0 Exclusion Criteria: Oxygen saturation of 95% or lower at rest

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Partial Rebreathing Mask<br>A novel membrane breathing mask which facilitates a partial rebreathing of expired gas (thereby raising systemic CO2), while allowing a diffusion of oxygen from the atmosphere to the user, through the membranes. | Device: Partial Rebreathing Mask<br>* Inducing normal CO2 for two hours a day for four weeks<br>* Other names: Balancair Mask;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Blood gas and acid/base status | pH, PCO2, PO2, Standard Base Excess | Once every week in the treatment period of four weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Hyperventilation symptoms | Nijmegen Questionnaire | once a week | 
| Breath Hold Tolerance |  | once a week | 
| Spirometric values | FEV1, FVC | once a week | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Hyperventilation, Chronic Idiopathic Hyperventilation, Dysfunctional Breathing, Respiratory Alkalosis, Respiratory Acidosis