Lung Compliance – Factors Affecting Pulmonary Ventilation (Nursing)

00:01 So the third factor that can affect pulmonary ventilation is lung compliance.

00:06 Lung compliance is the measure of a change in the lung volume that occurs with a given change in our transpulmonary pressure.

00:14 And basically it measures how much stretch the long has.

00:21 Our lung compliance is normally pretty high and this is due to the distance ability of the lung tissue.

00:27 Remember, there's a lot of elastic fibers and it's a pretty spongy organ, so there's a lot of ability to stretch.

00:35 Also because of the surfactant that is secreted by the type to alveolar cells.

00:40 We also have a decreased alveolar surface tension.

00:44 So this allows for the lungs to be able to expand pretty easily.

00:50 Higher lung compliance means that it's easier to expand the lungs.

00:56 We can explain lung compliance mathematically as well.

01:01 In this compliance is equal to a change in the volume of the lungs over the transpulmonary pressure or the intrapulmonary pressure minus the intrapleural pressure.

01:16 Compliance can be diminished by things such as fibrosis which causes our lungs to lose some of its elastic tissue and be replaced by scar tissue.

01:28 It can also be decreased by a reduction in the production of surfactant, which makes our alveoli smaller or more likely to collapse and lastly it can be reduced by a decrease in the flexibility of our thoracic cage.

01:46 So for example, if we have an injury that makes it harder for us to really expand our lung or expand our rib cage.

01:55 This can also reduce lung compliance as well, since the lungs move with the thoracic cavity.