Acid base 3 Flashcards
1
Q
what is metabolic alk
A
alk due to high serum HCO3-
2
Q
what is met alk comp?
A
slight rise in CO2 - hypocapnea
3
Q
what usually accompanies met alk
A
hypokalemia
4
Q
4 sources of extra HCO3-
A
- reduced ECF vol - increases [c]
- vomiting - loss of HCl
- hypokalemia and inclreased aldo - increased urine NH4
- hypokalemia - shifts H into cells
5
Q
2 ways vomiting raises HCO3-
A
- loss of HCl is compensated for and HCO3- is biproduct
2. lots of vomiting leads to volume depletion and increases [c]
6
Q
how does aldosterone increase HCO3- (2)
A
- RAAS (A2 esp) activate NHE3 pump to pull in more Na and this ends up reabsorbing more HCO3-
- aldosterone pushes our H into lumen which bind with NH3 and get more NH4+ flushed out
7
Q
how does hypokalemia affect HCO3- levels
A
- K comes out of cell and H goes in
- esp kidney cell thinks its acidemic
- tell it to behave as if it’s acidemic and reabsorb and make more HCO3-
8
Q
2 reasons for absorbing more HCO3- in met alk
A
- hypokalemia - body thinks acidemia
2. ECF volume depletion - RAAS acitvation
9
Q
how does vomiting create hypokalemia
A
- vomiting creates high levels of HCO3-
- body needs to excrete HCO3- as NaHCO3
- high urine flow takes lots of K with it
10
Q
how to diff met alkalosis with hypokalemia
A
hypertension present or not
11
Q
2 causes if high BP
A
- primary hyperadrenalism - Conns
2. renal art stenosis - kidney not getting blood so activates RAAS
12
Q
3 causes if normotensive
A
- diuretics
- vomiting
- barter or gitelman syndrome