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Relationship between bronchial responsiveness to hyperventilation with cold and methacholine in asthma
The Journal of Allergy and Clinical Immunology
|August 1, 1983
Summary
Asthma patients
Area of Science:
- Pulmonary Medicine
- Respiratory Physiology
Background:
- Asthma is characterized by bronchial hyperresponsiveness.
- Assessing bronchial hyperresponsiveness is crucial for asthma management.
Purpose of the Study:
- To compare methacholine (M) challenge with isocapnic hyperventilation (HV) of cold air.
- To determine if HV reflects nonspecific bronchial hyperresponsiveness.
Main Methods:
- Twenty-seven subjects with asthma underwent M and HV challenges.
- Dose-response curves were generated to find the provocative dose (PD20) causing a 20% fall in FEV1.
- PD20 values for M and HV were correlated.
Main Results:
- A significant correlation was found between M PD20 and HV PD20 (in liters per minute).
- HV reflects nonspecific bronchial hyperresponsiveness.
- Absolute ventilation level is the optimal measure for HV dose.
Conclusions:
- Isocapnic hyperventilation with cold air is a valid method for assessing nonspecific bronchial hyperresponsiveness in asthma.
- HV results correlate with methacholine challenge, supporting its use.
- HV dose should be standardized by ventilation volume.
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