<unk> , or pulmonary<unk> , is a measure of the<unk> 's ability to stretch and expand (distensibility of elastic tissue). In<unk> inical practice it is separated into two different measurements, static<unk>  and dynamic<unk> . Static<unk>  is the change in volume for any given applied pressure. Dynamic<unk>  is the<unk>  of the<unk>  at any given time during actual movement of air. Low<unk>  indicates a stiff<unk>  (one with high elastic recoil) and can be thought of as a thick balloon – this is the case often seen in fibrosis. High<unk>  indicates a pliable<unk>  (one with low elastic recoil) and can be thought of as a grocery bag – this is the case often seen in emphysema.<unk>  is highest at moderate<unk>  volumes, and much lower at volumes which are very low or very high. The<unk>  of the<unk> s demonstrate<unk>  hysteresis; that is, the<unk>  is different on inspiration and expiration for identical volume.
Lung compliance
Lung volumes
Airway resistance
Ventilatory threshold
Alveolar pressure
Alveolar–arterial gradient
Tidal volume
Peak inspiratory pressure