Resp physiology Flashcards
increasing acidity (or pCO2) means O2 binds less well to Hb
Bohr effect
increase pO2 means CO2 binds less well to Hb
Haldane effect
What 3 areas are in control of respiration
central regulatory centres
central and peripheral chemoreceptors
pulmonary receptors
What are the central regulatory centres which control respiration
medullary respiratory centre
apneustic centre (lower pons)
pneumotaxic centre (upper pons)
What signals central chemoreceptors to increase respiration?
raised [H+] in ECF stimulates respiration
What do peripheral chemoreceptors respond to that influences respiration?
raised pCO2 & [H+], lesser extent low pO2
where are peripheral chemoreceptors found?
carotid + aortic bodies
What are the 3 types of pulmonary receptor which play a role in respiration?
stretch receptors, lung distension causes slowing of respiratory rate (Hering-Bruer reflex)
irritant receptor, leading to bronchoconstriction
juxtacapillary receptors, stimulated by stretching of the microvasculature
Why does a fall in the partial pressure of oxygen in the blood lead to vasoconstriction of the pulmonary arteries?
Allows blood to be diverted to better aerated areas of the lung and improves the efficiency of gaseous exchange
What is lung compliance?
change in lung volume per unit change in airway pressure
Causes of increased lung compliance
age
emphysema - due to loss alveolar walls and associated elastic tissue
Causes of decreased lung compliance
pulmonary oedema
pulmonary fibrosis
pneumonectomy
kyphosis
