The respiratory therapist is performing a pulmonary function study on a patient who has periodic symptoms of asthma. The pulmonary function results are within normal limits

Question

What further testing can the therapist recommend to aid in either confirming or negating the possible diagnosis?
a. Inhaled methacholine challenge testing
b. Body plethysmography
c. Inhaled digitalis
d. Warm, humid air challenge

Answer 1

A
Because some patients have clinical manifestations associated with asthma but normal lung function, measurements of airway responsiveness to inhaled methacholine or a cold air challenge may be useful in confirming a diagnosis of asthma. A warm, humid air challenge would not be effective in producing results consistent with airway reactiveness. Body plethysmography is used to determine functional residual capacity. This would not be helpful in establishing a diagnosis of asthma.