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Peak flow meter

Recently, there has been recognized the necessity of monitoring a respiration function of a patient, inter alia a postoperative serious case. To effect this, it is essential to continuously monitor a flow velocity or flow rate of the respiration, as its basic approach. Asthma is recognized as a chronic disease which can manifest itself in bronchial inflammation of which the patient may be unaware, and has the ability to result in an acute attack under a variety of circumstances, resulting in the partial or complete obstruction of the breathing of the individual. In the treatment of such conditions as asthma it has been recognised that regular sampling of peak flow can reveal a trend in the state of the condition and provide a useful warning to the subject to take action that will prevent the condition worsening. Because of its chronic nature, asthma patients must be continuously on guard to become aware of symptoms which might forebode an attack. The use of effective anti-asthma drugs can substantially limit or eliminate such attacks, but need to be dispensed with care to prevent both over- and under-dosing. The peak-flow is often measured for people who suffer from asthma, bronchitis, mucoviscidosis, or who have been lung transplanted. Indeed, especially for those suffering from asthma, this measure allows the anticipation of an asthma crisis and, during treatment, allows the dosage of medicine intake. Asthma is typically monitored using a simple device to measure Peak Expiratory Flow Rate (PEFR). Peak flow meters are widely used for this purpose. Peak flow meters measure the peak expiratory flow rate, that is, the maximum rate of air flow which can be exhaled under various circumstances and at various times throughout the day. This permits the patient to monitor the respiratory function and receive warning of changes in respiratory function which may indicate an impending asthma attack. Peak flow meters measure the muscular effort to exhale forcibly from fully inflated lungs as well as the elastic recoil of the lungs and airways function. Thus, peak expiratory flow rate is a simple expression of a complex process of lung emptying.

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