Dead space (physiology)
Dead space (physiology)
Dead space in physiology refers to the volume of air that is inhaled that does not take part in the gas exchange, either because it (1) remains in the conducting airways, or (2) reaches alveoli that are not perfused or poorly perfused. In other words, not all the air we breathe in is available for gaseous exchange purposes. The air that does not participate in gaseous exchange is termed the dead space.
Pronunciation
- Dead space: /dɛd speɪs/
Etymology
The term "dead space" is derived from the concept that this portion of the air inhaled during respiration is "dead" to the process of gas exchange. It is a space in the respiratory system where air exists but does not contribute to respiration.
Types of Dead Space
There are three types of dead space: anatomical, alveolar, and physiological.
- Anatomical dead space is the volume of the conducting airways which transport gas to the alveoli. It includes the nose, pharynx, larynx, trachea, bronchi, bronchioles, and terminal bronchioles.
- Alveolar dead space is the volume of the alveoli which are ventilated but not perfused with pulmonary blood and therefore not participating in gas exchange.
- Physiological dead space is the sum of anatomical and alveolar dead space. It is usually slightly larger than the anatomical dead space due to diseases that cause certain areas of the lung to be ventilated but not perfused.
Related Terms
See Also
External links
- Medical encyclopedia article on Dead space (physiology)
- Wikipedia's article - Dead space (physiology)
This WikiMD dictionary article is a stub. You can help make it a full article.
Languages: - East Asian
中文,
日本,
한국어,
South Asian
हिन्दी,
Urdu,
বাংলা,
తెలుగు,
தமிழ்,
ಕನ್ನಡ,
Southeast Asian
Indonesian,
Vietnamese,
Thai,
မြန်မာဘာသာ,
European
español,
Deutsch,
français,
русский,
português do Brasil,
Italian,
polski