Analyser for functional respiratory volumes - has exhalation valve and inflatable sac with partial volume bleed syringe

摘要

The instrument is for measuring functional respiratory volumes and comprises a mouthpiece (1) which can be connected via an automatic breathing valve (2) to a gas storage tank (3). On the other side of the mouthpiece is an exhalation valve (4) leading to an exhalation receptacle (5), and a gas analyser. The exhalation receptacle has a capacity limit when full, and an indicator and/or signal generator is provided for indicating that it is filled with exhaled air. A large syringe (9, 10) is provided for extracting a given partial volume for gas analysis. The gas analyser is calibrated and provided with a scale to allow direct reading of the functional respiratory volume. The exhalation receptacle may consists of a non-stretch, non-rigid bag with a capacity of 50 1., or an elastic "bag in a box" with a capacity of 50 1.