Bronchial Provocation
Bronchial provocation (challenge) testing is the most commonly used and accepted approach for evaluating airway hyperresponsiveness (twitchy airways). Bronchial challenge testing utilizes a variety of agents and methods including aerosolized nonspecific pharmacological agents such as methacholine, specific agents such as latex, airborne irritants and occupational agents to assess airway hyperresponsiveness.
Methacholine Challenge
Specific Agent Challenge
Laryngoscopy
Preparing for a Bronchial Provocation
Methacholine Challenge
The most commonly used nonspecific challenge agent is aerosolized methacholine. In this test, the patient inhales an aerosol of one or more concentrations of methacholine. Results of pulmonary function tests (e.g., spirometry and specific conductance) performed before and after the inhalations are used to measure the response.
Performing the test
- You may do this test by performing pulmonary function tests of spirometry or lung volumes and spirometry.
- This is a timed test. You will be asked to inhale an aerosol concentration for 2 minutes.
- You will then do the pulmonary function test.
- You will continue repeating this procedure until the test is completed.
- You may have a laryngoscopy done at the end of the test.
- If required you will be given a bronchodilator treatment at the end of the test

Patient inhaling an aerosolized concentration during a Methacholine Challenge.
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Specific Agent Challenge
Bronchial challenge testing may also be done with different agents that are in your environment and/or workplace.
Performing the test
- You may do this test by performing pulmonary function tests of spirometry or lung volumes and spirometry.
- You will be exposed to the agent in the environmental chamber.
- You will then do the pulmonary function test.
- You will continue repeating this procedure until the test is completed.
- You may have a laryngoscopy done at the end of the test.
- If required you will be given a bronchodilator treatment at the end of the test

Specific Agent testing in the environmental chamber.

Patient inhaling an irritant for a specific agent challenge
How should you prepare for a bronchial provocation test?
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Laryngoscopy
This procedure is done to visualize the upper airway and most commonly used to rule out vocal cord dysfunction. The technologist assists the physician by providing all necessary equipment and medications. This procedure involves the use of a small flexible fiberoptic scope inserted through the patient’s anesthetized nasal passage. The laryngoscopy is often done following an exercise or bronchial challenge test. Actual visualization lasts approximately two minutes. The procedure is recorded on a DVD for the patient’s medical record.

Technologist showing the laryngoscope to the patient.
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