Bronchial Hyperreactivity During Histamine Passive Exposure

Study Overview
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Brief Summary
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Bronchial hyperresponsiveness consists in excessive response to bronchial stimuli.Bronchial challenge test is used to confirm/exclude asthma (metacholine or histamine).Protection are used to avoid passive exposure of the technicians performing the test, despite the absence of evidence that they could develop a bronchoconstriction even if they suffer from BHR.The purpose of the study is to determine if patients with a high level of bronchial hyperreactivity and exposed passively to histamine during a bronchial challenge, are developing a bronchoconstriction, when placed in the same conditions that the technicians performing these tests.

Detailed Description
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Bronchial hyperresponsiveness (BHR) consists in excessive response to bronchial stimuli.Bronchial challenge test is used to confirm/exclude asthma.BHR is also present in other diseases such as allergic rhinitis, Chronic Obstructive pulmonary disease,heart failure.. Thes test is performed with metacholine or histamine with spirometric documented response to incremental doses.Protection are used to avoid passive exposure of the technicians performing the test, despite the absence of evidence that they could develop a bronchoconstriction if they suffer from BHR. The purpose of the study is to determine if patients, newly diagnosed with a high level of bronchial hyperreactivity and exposed passively to histamine during a bronchial challenge, are reacting to histamine when placed in the same conditions that the technicians performing these tests.

Official Title
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Are Technicians Showing Bronchial Hyperreactivity Able to Safely Perform Bronchial Provocation Tests?

Conditions
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Asthma, Bronchial Hyperresponsiveness

Intervention / Treatment
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* Drug: histamine-benzylic alcohol (magistral preparation)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: adult patients with positive histamine challenge test (first dose) Exclusion Criteria: other active respiratory disease

Ages Eligible for Study
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Minimum Age: 18 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: Prevention
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: asthma patients<br>patients who show a positive response at the first dos of histamine challenge test will be enrolled | Drug: histamine-benzylic alcohol (magistral preparation)<br>* passive exposure to histamine during a bronchial hyperresponsiveness challenge<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| spirometric values in patients exposed passively to histamine during BHR challenge |  | 1 hour | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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asthma, bronchial hyperresponsiveness, histamine challenge test, spirometry