The respiratory system and homeostasis.
Respiratory homeostasis is concerned with the regulation of a blood gas composition that is compatible with maintaining cellular homeostasis. Provided that the lung-capillary exchange barrier does not prevent the exchange of gases, then blood leaving the lung will have oxygen and carbon dioxide partial pressures that are similar to the average values found in the alveoli. Alveolar ventilation establishes these values. If blood gas composition, especially of carbon dioxide, moves outside the homeostatic range, the change is detected by chemoreceptors and respiratory responses are promoted which change alveolar ventilation, alter alveolar gas composition and so reverse the change. Ventilation therapies provide the means of artificially restoring alveolar gas composition. In general terms, they do this by raising the partial pressure of oxygen within the alveoli either by using oxygen-enriched gas mixtures, or by improving the ventilation of alveoli using positive pressure.
Clancy
J
J
McVicar
A
A
D001784:Blood Gas Analysis; D006706:Homeostasis; D006801:Humans; D011659:Pulmonary Gas Exchange; D012121:Respiration, Artificial / Q000009:adverse effects / Q000379:methods; D012143:Respiratory Physiological Phenomena