Renal: Renal Regulation of Acid-Base Balance Flashcards
Acids and bases are subject to the same constraints of input and output balance as other substances.
There are multiple routes for the entry of acids or bases
Balance Principle
How do Acids and Bases enter?
- Metabolism
- Activity of the GI tract adding acids or bases
- Processing ingested food
- Metabolism of stored fat and glycogen
- Kidneys
What is a Buffer?
Prevents large changes in pH
Maintain normal range
Doesn’t have an infinite capacity
What is the ECF’s buffer?
C02-bicarbonate system.
( CO2 + H2O H2CO3 HCO3- +H )
ECF is the 1st line of defense of ingested acids
Carbonic Acid is what formula?
H2CO3
What are the ICF’s buffers?
Protein
Phosphate
K+/H+ Exchanger.
True/False:
More buffering in the body is done by the ICF.
True. Because ICF has more fluid there are LOT more buffers in the ICF
What’s the normal pH range?
7.35-7.45
Explain events of Acidosis
Too much acids outside the cell; causes K+ to move out and H+ to move in.
The H+ ion is buffered inside the cell
The concentration of CO2 is essentially constant. Is CO2 an acid or base?
Acid
CO2 changes impact pH (short-term). What’s one of the long-term effects of CO2 changes?
Impact on Kidney’s function of Bicarbonate.
True/False: Changes in H+ content changes BICARBONATE levels, NOT CO2.
True
What are the characteristics of Bicarbonate?
Freely Filtered
Plasma concentration of 24mmol/L
Normal GFR is 180L/day
What’s the Filtered Load of Bicarbonate?
Plasma Concentration - 24mmol/L
Normal GFR - 180L/day
GFR x Px = 4320mmol/day
True/False:
About 100% of Bicarbonate is reabsorbed
True.
Bicarbonate is 100% reabsorbed regardless of too much acid/base in body.
