oxygen dissociation curve - lek

[ArchivalUser]

where does it shift, right or left, after extensive physical training at high altitudes in a healthy individual?

[ArchivalUser]

this one is from NBME 3/4

[ArchivalUser]

HIGH ALTITUDE always RT bec of hypoxia( Pa O2and PAO2 remain low even after acclimitization) and increase 2,3 DPG
i hope it is clear

[ArchivalUser]

its clear, almanfi, thanks!! I was going for resp alcalosis at high altitude

[ArchivalUser]

the FA pnemonic also helps...
CADET fce RIGHT..i.e shifts to rt. with increase of
C...C02
A...ACID/ALTITUDE
D...DPG(2,3 DPG)
E...EXERCISE
T...TEMPERATURE

[ArchivalUser]

thanks!!!

[ArchivalUser]

on the right side of the body, blood is going up. so everything in term of O2 dissociation curve is going to increase.
on the left side, blood is going down, so everything decreased.

exception is the PH. so use H+ concentration instead.

[ArchivalUser]

initially, you'll have lower P50 for hemoglobin. so that means high affinity and difficult O2 unloading (shift to the L). after 12-24 hrs, there will be increased 2,3-DPG in RBC which will shift it back to the right so that normal P50 is restored. got it from kaplan! here's more info:

adaptations to high altitude: increased respiration, respi alkalosis, lower P50 (initially), increased glycolysis rate, increased 2,3 DPG, normal P50 for Hb restored by increased 2,3 DPG, increased Hb and Hct (days to weeks)

[ArchivalUser]

oh, and according to the kaplan video lecture, athletes train at high altitudes so that when they return at sea level, O2 unloading will be much easier (shift to the R) since they have adapted to the condition at high altitudes where O2 unloading is more difficult.

[ArchivalUser]

thanks, mdsurgeon and okazakimd, now this is stuck in my head ) (hopefully fowever)