5.4 Pulmonary Flashcards
what is CO2 and O2 environments like in lungs and tissues?
lungs= increase O2; decrease CO2 tissue= decrease O2; increase CO2
globin
protein that can carry CO2 and H+
heme
protoporphyrins that actually carries O2
*also has higher affinity for CO than O2 by 210x
define capacity
- capacity= the most amount of oxygen Hb that blood can carry
- content= what do they actually have
Hb vs Hb-
Hb= deoxyhemoglobin Hb-= oxy
1 gram of hemoglobin carries ____ mL of O2 at 100% saturation
1.34
how muc Hb in 100 mL of blood?
15 g Hb (hemoglobin)
-tends to be higher in males
when one heme group binds to O2 it changes the affinity of?
the other heme subunits so they can bind to O2 quicker
-can go from deoxy to a fully saturated oxy quickly
lack of functional Hb means?
anemia!
*all anemia’s have this ONE thing in common
how do you calculate capacity?
take 1.34 carrying capacity of Hb times how much Hb you have
a PaO2 of 100 torr results in ____% saturation of Hb
97%
-not a lot of room for improvement
actual O2 content in blood is due to?
physically dissolved O2 and O2 carried by Hb
*both determined primarily by Pa O2
how do you calculate content?
take capacity times the % of saturation
1) capacity depends on?
2) content depends on?
3) % saturation depends on?
1) amount of functional Hb
2) saturation of the functional Hb you have
3) PP of arteriolized O2 (PaO2)
typical pH of blood an d ECF?
7.4
primary determinant of whether oxyheme releases O2 is?
PP of O2
*lower PP, greater the oxyheme release
standard conditions?
7.4 pH
40Torr of PCO2
37 degrees
basic vs acidic environments
- basic= upward L-shift; greater affinity
- acidic= downward R-shift; lower affinity
- –indicates metabolically active and release of O2
high vs low CO2 environments
- high CO2= upward L-shift; greater affinity
- –indicates metabolically active and release of O2
- low CO2= downward R-shift; lower affinity
high vs low temp environment?
- high temp= upward L-shift; greater affinity
- –indicates metabolically active and release of O2
- low temp= downward R-shift; lower affinity
No 2,3 DPG vs more than normal ?
- none= upward L-shift; greater affinity
- more= downward R-shift; lower affinity
- –indicates metabolically active and release of O2
Hb gets an increase in O2 affinity when acidic or basic?
alkalic / basic
why is 2,3 BPG levels important to check when giving blood
bc if the blood is low on BPG, then the blood will bind to and hold onto oxygen (aka not release it ats needed areas)
at high altitude you make more or less 2.3 BPG? important why?
more
**important bc it increases the Hb tendency to release oxygen
CO2 binds to the?
globin subunit of the deoxygemoglobin
how is CO2 carried?
1) dissolved in plasma (5-10%)
2) as carbamino compounds (5-10%)
3) as bicarbonate (70-90%)
what happens when deoxyhemoglobin gets into a high O2 environment?
CO2 and proton comes OFF of the globin part and oxygen then bidns to the heme subunit
loading and unloading O2 and CO2 at the lungs and tissures
1) deoxyhemoglobin can bind H+ and CO2 HbH-CO2
2) high PP of O2 will displace the H+ and CO2
