Certified Pulmonary Function Technologist (CPFT) Practice Exam

If a patient is tested for asthma and shows normal spirometry with no response to a bronchodilator, what should be examined next?

1. Peak flow rate

2. sGaw (specific airway conductance)

3. Lung capacity

4. Airway resistance

The correct answer is: sGaw (specific airway conductance)

In the context of asthma diagnosis and management, if a patient has normal spirometry results and does not show a response to a bronchodilator, the next step often involves evaluating specific airway conductance (sGaw). sGaw is a measurement that provides insight into the airway's ability to conduct air. It reflects airway caliber and responsiveness more sensitively than routine spirometry, particularly in cases where airway obstruction may not be present at rest but could still be functionally relevant. Asthma is characterized by variable airway obstruction that may not always be detectable in standard spirometry tests. By assessing sGaw, healthcare providers can detect subtle changes in airflow dynamics that might indicate bronchial hyperreactivity or other functional abnormalities that could be missed with traditional tests. This makes sGaw a valuable tool when initial tests do not indicate asthma or other obstructive conditions. While assessing peak flow rate, lung capacity, and airway resistance can provide useful information in the evaluation of patients with respiratory conditions, they do not have the same direct correlation with the swift detection of airway reactivity seen with specific airway conductance measurements. Thus, following up with sGaw after normal spirometry and lack of bronchodilator response is a logical and clinically relevant next step.