Lecture 26 - Control of ventilation Flashcards
where is the respiratory center located
brainstem
where are the chemoreceptors for ventilation located
central and peripheral
what does the respiratory center control
autonomic (non-voluntary) breathing by controlling action of respiratory muscles
what does the medulla control
dorsal and ventral respiratory group
what does the pons control
pneumotaxic and apneustic center
describe the job of the medullary respiratory system
- the basic rhythm of ventilation
- initiate and modify contraction of muscles for inspiration and expiration
what is the pneumotaxic center responsible for
limits inspiration and prevents over-inspiring
what is the apneustic center responsible for
controls deep inspirations and is affected by anesthetic drugs/injury
what do the central chemoreceptors detect
CO2
what do peripheral chemoreceptors detect
PaO2 and blood pH
what is most important for minute-minute control of ventilation
central chemoreceptors
where are the locations of peripheral chemoreceptors
- aortic arch
- carotid bodies
the central chemoreceptor is activated by
H+ concentration
T/F: CO2 easily diffuses into CSF
TRUE
T/F: CCR can sense O2 levels when carbon dioxide is inadequate
FALSE
when increased H+ is detected, what happens
- increased ventilation rate
- decreased PaCO2
peripheral chemoreceptors respond to
- decreased arterial PaO2 (only very low; <50)
- increased PaCO2 and H+
what takes over ventilation if PaO2 is too low
peripheral chemoreceptor
where are the locations of stretch receptors
- lung tissue
- respiratory muscles
describe the Hering-Breuer Inflation Reflex
- increase lung volume
- increased firing stretch receptors decrease further inspiration
- stimulate expiration
describe J receptors
- juxta capillary receptors
- activated with pulmonary dysfunction
- causes rapid, shallow breathing
describe irritant receptors
- located between airway epithelial cells
- response to noxious gas, smoke, etc.
- bronchoconstriction and decreased ventilation
what two changes to the airway impact ventilation
- bronchoconstriction
- bronchodilation
what is the sympathetic nervous system’s relationship with airways
B2 receptors activated and cause bronchodilation
what is the parasympathetic nervous system’s relationship with airways
muscarinic receptors activated and cause bronchoconstriction
what is the non-adrenergic inhibitory pathway’s relationship with airways
release nitric oxide to smooth muscle and causes bronchodilation
what is the most important factor in control of ventilation
PaCO2
the relationship between PaCO2 and Vmin is ____
direct
