Flashcards in 19. Response to high altitude Deck (18):
1. increased ventilation
2. increased erythropoietin
3. increased 2.3 BPG
4. Cellular changes
5. RIght ventricular hypertrophy
6. Increased renal exertion of HCO3--
PCO2- ? ( mechanism)
because of the increased ventilation
ventilation ( chronic
decreased atmospheric PO2--> decreased PaO2--> increased ventilation --> decreased PaCO2
heart structure changes ?
chronic hypoxic pulmonary vasoconstriction results in RIGHT ventricular hypertrophy
ncreased 2.3 BPG ---> bind to Hb so that
1. increased erythropoietin --> increased hematocrit and Hb ( chronic hypoxia)
2. Increased renal exertion of HCO3- to compensate for respiratory alkalosis
compensation of respiratory alkalosis
increased renal excretion of HCO3
renal excretion of HCO3 can augment with
• A hiker goes up to high altitudes for an afternoon. What happens to his ventilation, PaO2, and PaCO2?
PaO2 and PaCO2 decrease, as ventilation is increased
• A patient has been living high in the mountains for years. What happens to his erythropoietin levels?
In response to high altitude, erythropoietin levels are increased, as are hematocrit and hemoglobin
A hiker ascends a mountain. What happens to his level of 2,3-bisphosphoglycerate?
In response to high altitude, the 2,3-BPG level increases
• What substance binds to hemoglobin so that hemoglobin releases more oxygen as a physiologic response to high altitude?
A hiker climbs up a tall mountain. What cellular change occurs in response to this?
An increase in the number of mitochondria occurs in response to high altitude
The increased renal excretion of bicarbonate that is seen in response to high altitude compensates for what?
The respiratory alkalosis that occurs as a result of increased ventilation
The increased renal excretion of bicarbonate that is seen in response to high altitude can be augmented using what?