A pulmonary function technologist is reviewing an asthma action plan. The patient takes a low-dose inhaled corticosteroid and a long-acting beta2-agonist twice daily. The patient's personal best peak flow is 600 L/min. Which of the following instructions should be given to the patient when the peak flow drops to 500 L/min?

A patient will undergo bronchial provocation testing with methacholine chloride (Provocholine). Baseline spirometry reveals the FVC is 4.00 L and FEV1is 3.00 L.
The provocative dose 20% (PD20) can be calculated when which of the following measurements occur?

Which of the following is an appropriate reason to perform a multiple-breath nitrogen washout test?

The following data are obtained after an exercise (stress) test for exercise-induced asthma:

Based on these data, the post-exercise FEVi represents a decrease of approximately

A helium dilution test has just been performed on a patient. The following results are obtained:
FRC 5.0 L VC 4.0 L ERV 1.5 L
TLC was calculated to be 6.0 L by plethysmography. From this information, a pulmonary function technologist should conclude that the patient