L25: Breathing In Unusal Environments Flashcards
How many phases does exercise have
3
What is phase 1
Neural phase information that makes the limbs move are take to the cortex
What is phase 2
Humoral phase
Information is carried in the blood e.g p02, pc02 etc
What is phase 3
Steady state
What is hyperpnea
When ventilation increases appropriately due to increasing metabolism so paco2 does not increase
What is hyperventilation
After ventilation being proportional to metabolic demands, the ventilation increases disproportionately and paco2 decreases
What is an anaerobic threshold
An accumulation of lactic acid (low ph)
When can hyperpnea occur
During exercise
Why does ventilation increase more in exercise than at rest
The sensitivity to carbon dioxide increases
What causes an increase of carbon dioxide sensitivity during exercise
Adrenaline
What happens to the barometric pressure and therefore oxygen when we increase altitude
Decreases
What happens to ventilation as you go up an altitude
Increases
Why do we get hyperventilation in high altitudes
Hypoxia stimulates peripheral chemoreceptors
How does hyperventilation affect carbon dioxide and what does it lead to
Hypocapnia
What does hypocapnia lead to
Decrease in ventilation
Overall at low to moderate altitude was happens to the ventilation
No change in ventilation as hypoxia and hypocapnia responces cancel it out
What happens when you get to even higher altitudes
Hypoxia wins and takes control resulting in hyperventilation
What does hypocapnia result in due to increase in hyperventilation at higher altititudes
Respiratory alkolosis
Which organ compensates for respiratory alkolosis
Kidney
How is someone able to survive without supplementary oxygen at mountain Everest
An increase in ph (due to alkolotic blood) shifts the hb saturation curve to the left via the Bohr effect. The person will have a higher saturation of hb at a lower partial pressure of oxygen.
What happens to atmospheric pressure as you dive
Increases
Why is a snorkel never longer than 40cm
If you dive a lot lots of pressure will build onto your thorax so the person will not be able to breath
What will a narrow tube of snorkel create
Resistance so air wont get into the snorkel quick
What happens to the gas density as you go down to deep levels in diving
Increases
