A patient has normal pulmonary and cardiac function. Which of the following is most likely when the patient reaches the anaerobic threshold during incremental stress testing?

The following data were obtained from a bronchial challenge test:

APC20of 2 mg/mL was obtained the next day in another laboratory. Which of the following is the most likely explanation for these data?

A smoking cessation program using a nicotine patch is started for all smokers in a factory. Results revealed that smokers who reported they had quit had exhaled carbon monoxide levels less than 6 ppm. A pulmonary function technologist should conclude that

During calibration of a spirometer, injection of air with a 3-liter syringe results in the following:
Using another 3-liter syringe, air is again injected with the following results:
A pulmonary function technologist should conclude that the

Which of the following is the most reliable indicator that a patient has achieved his maximum exercise capacity during a progressive exercise (stress) test?