CVR 32 altitude phys

Question 1

A 21-year old woman on a hiking holiday in the Himalayas is at an altitude of 4,000m. She has had a headache for 2 days. She awakes with dyspnoea and subsequently cannot walk due to extreme dyspnoea.

Answer 1

Acute mountain sickness with pulmonary eodema

Question 2

Treatment of acute mountain sickness

Answer 2

descent
dexamethasone
gamow bag
prohylactic acetazolimide

Question 3

Chronic effects of altitude

Answer 3

Cardiac output and heart rate return towards normal but not pulmonary arterial pressure. There is increased tissue vascularity, erythropoietin, HCT [to 60-65%], haemoglobin (to 22 g/dl), Blood Volume (by 20-30%) and diffusing capacity

Question 4

where is the death zone

Answer 4

26,000 feet

Question 5

5 acclimatization factors

Answer 5

increased pulmonary ventilation
increased RBC number
Increased diffusing capacity of lungs
increased vascularity of perifpher
increased abilit of tissue cells to use 02

Question 6

Three main causes of chronic mountain sickness

Answer 6

increased blood viscosity polycythemia
pulmonary arteriole vasoconstriciton due to hypoxia
right heart failute
pulmonary shunt blood dlow due to alvelore spasm