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Respiratory Study Guide

Respiratory Volumes

Respiratory volumes

1). Respiratory Volumes:

i). Tidal Volume:

Amount of air inhaled & exhaled in one breath at rest.

ii). Inspiratory Reserve Volume

The amount of air that can be forcibly inspired beyond the tidal volume

iii). Expiratory Reserve Volume

The amount of air that can be forcibly expired beyond the tidal volume.

iv). Residual Volume

Is the air still remaining in the lungs after forced expiration.

This keeps the alveoli inflated.

2). Respiratory Capacity

Capacities involve 2 or more volumes.

i). Inspiratory Capacity:

Total amount of air that can be inspired after tidal expiration or

Inspiratory Reserve Volume + Tidal Volume

ii). Functional Residual Capacity

The air remaining in the lungs after tidal expiration.

Expiratory Reserve Volume + Residual Volume

iii). Vital Capacity

The total amount of exchangeable air

Expiratory Reserve Volume + Inspiratory Reserve Volume + Tidal Volume

3). Dead Space refers to the inspired air that fills the conducting system and is not involved in gas exchange.