Bronchoprovocation methods: direct challenges.

Donald W Cockcroft

doi:10.1385/criai:24:1:19

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PubMed · 12644716

Bronchoprovocation methods: direct challenges.

Donald W Cockcroft

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Abstract

Inhalation challenges with direct-acting stimuli histamine and methacholine are widely used to measure airway responsiveness. Three widely used methods (2-min tidal breathing method, breath-activated dosimeter method, hand-held manual nebulizer) are described. Careful standardization is important so as to best differentiate normal from increased airway responsiveness and to permit comparison between methods. With current methods standardized as suggested by the ATS, a methacholine (or histamine) PC(20) > 16 mg/mL is considered normal. A PC(20) < 16 mg/mL is highly sensitive for current symptoms of asthma. Interpretation of methacholine or histamine inhalation test requires that symptoms be current (within a few days) and that FEV(1) be normal.

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Administration, Inhalation Asthma Bronchial Provocation Tests Histamine Humans Methacholine Chloride Nebulizers and Vaporizers Practice Guidelines as Topic Sensitivity and Specificity Comparative Study Journal Article Review

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Donald W Cockcroft. 2003. Bronchoprovocation methods: direct challenges.. https://doi.org/10.1385/criai%3A24%3A1%3A19

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