Control of Respiration

Respiration control

Controlled by high PCO2 or low PO2

Stimulus to breathe

When PCOs is more than 40mmHg

Hypercapnia

When blood PCO2 is more than 45mmHg, increased carbon dioxide = increased carbonic acid = increased hydrogen ions = acidosis which can depress nervous system

Main causes of hypercapnia

Hypoventilation = inadequate oxygen delivery and carbon dioxide removal and lung disease = decreased gas exchange

Consequences of hypercapnia

Respiratory acidosis, decreased cns activity, lethargy, coma and death

Hypocapnia

When blood PCO2 is less than 40mmHg, no breathing until PCO2 reaches over threshold, decreased carbon dioxide = decreased carbonic acid = decreased hydrogen ions

Main causes of hypocapnia

Hyperventilation = increased carbon dioxide removal

Consequences of hypocapnia

Respiratory alkalosis, increased cns activity, pins and needles, dizziness

pH balance in body

pH maintained in narrow range for homeostasis

How does the body compensate for acidosis or alkalosis

Chemical buffers that occur in seconds, respiratory changes which occur in minutes, hydrogen ion excretion and carbonic acid synthesis in kidneys which occurs in hours or days