111214 ventilatory response to exercise Flashcards
what happens to alveolar O2 and CO2 with exercise?
initially, alveolar O2 for the test subject decreased a little and CO2 increased a little. but with time, both went back to normal values
response to exericise–describe what happens in timing to frequency and tidal volume
with increased workload, big jump in tidal volume. breathing frequency slowly increases
what happens when you increase the airway resistance for the subject during exercise?
Co2 and O2 are not maintained at normal levels
how do pulmonary and alveolar ventilation change with increases in metabolic rate from rest to about 60% of maximal metabolic rate? how does it change above 60%?
from rest to about 60% of metabolic rate: pul and alveolar ventilation increase in proprtion to the icnrease in metabolic rate
above 60% of metabolic rate: pulm and alveolar ventilation increase proportioantely more than metabolic rate so you have hyperventilation
during exercise above 60% of maximal capacity, what happens to pH?
decreases bcause of increased lactic acid production
at high work rates (above 60%), what happens to PaO2?
it doesn’t really increase
at high work loads, what happens to A-a PO2 difference?
increases
at high work loads, what happens to diffusing capacity?
it doesn’t increase in proportion to the increase in work rate
at high work loads, what happens to the alveolar to capillary driving pressure?
increases
at high work loads, what happens to PaO2?
stays normal
temporal pattern of ventilation after exercise
has two components-fast and slow
it remains unclear what is responsible for the exercise hyperpnea
respiratory quotient vs respiratory exchange rate
ratio btwn CO2 produced and O2 consumed
respiratory quotient would need to be measured at the tissues, invasively
RER is measured by mouth
