Bicarbonate Flashcards
1
Q
what’s the formula that makes bicarbonate
A
water + CO2 = HCO3 + H+
2
Q
what does pH approximate
A
HCO3 / pCO2
3
Q
What the kidney does
A
• Bicarbonate filtration • Bicarbonate reabsorption • Bicarbonate regeneration by: – Titratable acid excretion – Ammonium excretion
4
Q
bicarbonate regeneration is by two processes
A
titrate acid excretion
ammonium excretion
5
Q
buffers in urine
A
- urate
- creatinine
- beta-hydroxybutyrate
6
Q
ammonium excretion
A
Glutamine - taken up by renal tubule, converted to glucose or co2 and water and ammonium is the by product which is excreted into the urine and this process uses up protons
7
Q
where glutamine formed
A
liver and the muscles and is triggered by a decrease in pH
8
Q
Respiratory acidaemia
A
- Rise in pCO2
- Parallel change inside the renal tubule cells
- Intracellular acidaemia
- Increases uptake & use of glutamine & hence ammonium excretion
- Increasing bicarbonate regeneration
- Low intracellular pH increases tubular proton secretion and ensures optimum reabsorption of bicarbonate
9
Q
Respiratory alkalaemia
A
- Fall in pCO2
- Parallel change inside the renal tubule cells
- Intracellular rise in pH
- Proton secretion falls
- Bicarbonate reabsorption rfalls
10
Q
What happens when kidney function is impaired?
A
- AKI & CKI
- Damage to glomerulus & tubule
- Will result in metabolic acidaemia
- Decrease in ammonium secretion by tubule