Final answer:
A peak flow meter measures the highest airflow during a forced expiration. It is a critical self-monitoring tool for asthma patients to manage their condition and detect airflow obstruction.
Step-by-step explanation:
The peak flow meter measures the highest airflow during a forced expiration. This tool is crucial for individuals with asthma as it allows them to monitor their lung function at home, helping to detect early signs of an asthma attack. Measurement of peak expiratory flow gives an idea of how well the air is moving out of the lungs and can assist in managing the condition effectively. It does not measure inspiratory airflow or the airflow during normal respiration.
Spirometry, which includes measuring forced expiratory volume (FEV) and forced vital capacity (FVC), is a clinical method to diagnose lung diseases such as asthma, by analyzing airflow and lung volumes. In patients with asthma, due to the resistance in the lung, there is usually a reduced FEV1/FVC ratio indicating airway obstruction and difficulty in exhalation.