Acid/Base balance by Kidneys Flashcards
Buffering equation
HCO3- + H+ → H2CO3 <ca>⇒ CO2 + H2O</ca>
Normal values:
pH
CO2
HCO3
pH: 7.4 (7.35-7.45)
CO2: 40 mmhg (35-45)
HCO3: 24 mM (20-28)
acute respiratory acidosis
Increased CO2
decreased pH
increased HCO3-
normal BE
chronic respiratory acidosis
increased CO2
close to normal pH
very increased HCO3-
> +2 BE
acute metabolic acidosis
decreased CO2
decreased HCO3- or increased H+
decreased pH
negative
Chronic metabolic acidosis
decreased CO2
decreased HCO3-
about normal pH
negative
Acute respiratory alkalosis
decreased CO2
decreased HCO3-
increased pH
normal BE
chronic respiratory alkalosis
decreased CO2
very decreased HCO3-
about normal pH
negative
acute metabolic alkalosis
increased CO2
increased HCO3-
increased pH
positive >+2 BE
chronic metabolic alkalosis
increased CO2
increased HCO3-
about normal pH
positive >+2 BE
anion gap
Na+ - (Cl- + HCO3-)
high anion gap = addition of acid
normal anion gap = loss of base
Where does bicarb reabsorption take place?
proximal tubule
thick ascending limb of Henle
Collecting duct
Under normal conditions, do you excrete bicarb in urine?
No
How many millimoles of bicarb in our ultrafiltrate?
How much do we reabsorb?
24 millimoles
100%
Generally, diuretics work by
altering osmolality of the urine filtrate, preventing the reabsorption of the water, resulting in an increase of urine volume.
* usually lose Na, then water follows