The commercially available instruments are much smaller than their traditional research counterparts and are much easier to use and maintain. The cost of the instruments is in the range of $12,000 to $20,000. Laboratory space requirements are minimal: the instrument is usually mounted on an adjustable arm attached to a small table or cart. Technical personnel familiar with spirometry or other pulmonary function tests will not have difficulty learning the techniques to used to set up and calibrate the instruments. However, it should be stressed that the devices cannot be considered maintenance free. Like spirometers or body plethysmographs, they contain flowmeters and pressure transducers the accurate calibration of which is essential to obtaining accurate data.
Will these devices replace spirometry or plethysmography in the routine testing laboratory? Probably not, in the near future. Several studies have shown results of FO testing to be no more sensitive than spirometry in detecting disease or in correlating with symptoms. Because standard reporting procedures are not firmly established, and because there are only a few large population studies showing the range of normal and the patterns of abnormality with disease, the interpretation of the data should be performed very conservatively. itat on
In conclusion, the determination of pulmonary resistance parameters using FO is a technique that has been in development for nearly 30 years, but recent efforts at automating the technique may make it available for wider clinical application. The potential advantages of FO include the ability to measure lung function with minimal patient effort, making testing available in the very young or in patients unable to perform spirometry or plethysmographic resistance tests’ and the ability to separate resistance components of the system (upper airway vs lower airway). At their current state of development and validation, these tests do not replace existing pulmonary function tests.
Category: Pulmonary Function
Tags: flow-volume, Forced oscillation, negative expiratory pressure, nitric oxide