Peak expiratory flow meter capable of spirometric test for asthma monitoring

The present study designed a miniatured air chamber installed within a commercialized peak expiratory flow meter (PEFM), to obtain continuous flow signal measurement. Pressure in the chamber accurately estimated the flow with a volume error <1%, well meeting the criteria of the American Thoracic Society (ATS), which enabled spirometric parameters evaluation. Data communication thru RS232C by the electronic circuitry would be of great use for remote management of asthma.