What device is specifically used to measure the peak expiratory flow rate (PEFR)?

The peak flow meter is the device specifically designed to measure the peak expiratory flow rate (PEFR). This handheld instrument provides a simple and effective means of determining how quickly a person can exhale air from their lungs after taking a deep breath. It is particularly useful for monitoring conditions such as asthma, where fluctuations in airflow can indicate management of the condition or the onset of an exacerbation.

The peak flow meter operates on the principle of measuring the maximum speed of airflow during expiration, giving real-time insights into lung function. Regular use can help patients track their condition and adjust their medication or seek medical advice if their readings fall below normal ranges.

In contrast, a spirometer is a broader tool that measures various parameters of breathing, including tidal volume, vital capacity, and forced expiratory volume, but it does not focus solely on peak expiratory flow. A pulsometer typically assesses pulse oximetry or heart rate, while a capnometer measures the concentration of carbon dioxide in exhaled air. These devices serve important functions but do not measure PEFR, which is why the peak flow meter is the correct choice for this specific task.