What is the purpose of a peak flow meter in asthma management?

A peak flow meter is a valuable tool in asthma management primarily used to assess asthma control and monitor lung function. It measures the peak expiratory flow rate (PEFR), which indicates how well air moves out of the lungs. This data helps patients and healthcare providers understand how well the asthma is controlled and can identify when asthma symptoms may be worsening, even before a full-blown attack occurs.

Monitoring PEFR can guide treatment decisions, such as adjusting medications or responding to changes in asthma symptoms. By regularly using the peak flow meter, individuals with asthma can track their lung function over time, providing crucial information for effective asthma management.

The other options listed do not relate to the function of a peak flow meter. Blood pressure measurement, medication delivery, and heart rate evaluation are managed through different medical devices and practices, making those options incorrect in this context.