Anatomical dead space

Definition

Anatomical dead space is the portion of the respiratory system where air is present but not involved in gas exchange. It includes the trachea, bronchi, and bronchioles up to the terminal bronchioles.

5 Must Know Facts For Your Next Test

1. Anatomical dead space typically amounts to about 150 milliliters in an average adult.
2. It does not participate in gas exchange because these areas lack alveoli.
3. The volume of anatomical dead space can be affected by factors such as body size and posture.
4. Understanding anatomical dead space is crucial for calculating effective alveolar ventilation.
5. It differs from physiological dead space, which includes both anatomical and any additional spaces where gas exchange is impaired.

Review Questions

• What components of the respiratory system are included in anatomical dead space?
• How much air typically resides in the anatomical dead space of an average adult?
• Why does air in the anatomical dead space not participate in gas exchange?

Related terms

Alveolar Ventilation: The amount of fresh air that reaches the alveoli per minute.

Physiological Dead Space: Includes both anatomical dead space and additional volumes where gas exchange is impaired.

Alveoli: Tiny air sacs within the lungs where gas exchange with the blood takes place.