Bronchial challenge test
Sometimes, to assess the reversibility of a particular condition, a bronchodilator is administered to counteract the effects of the bronchoconstrictor before repeating the spirometry tests. This is commonly referred to as a reversibility test, or a post bronchodilator test (post BD), and may help in distinguishing asthma from chronic obstructive pulmonary disease. Also, a DLCO test can be used to distinguish asthma from COPD.
False positives and negatives are possible in the bronchial challenge test. In addition, asthma may be temporary due to an exposure to noxious stimuli or exercise.
The bronchial challenge test is physically demanding, and the results can be affected by muscular weakness or exhaustion. The inhaled drug can stimulate the upper airway sufficiently to cause violent coughing. This can make spirometry difficult or impossible. This test is contraindicated in patients with severe airway obstruction due to the obvious worsening of the obstruction. Also contraindicated by the presence of an aortic aneurysm, as spirometry will increase blood pressure, in proportion to both the patient's effort and the degree of obstruction in the lungs.
- Subtype Of
- Pulmonary function tests
- https://en.wikipedia.org/wiki/Bronchial challenge test
- Relevant Specialties
- Respiratory and Sleep Medicine
- Medical Conditions
- Chronic obstructive pulmonary disease