PHS3300 Acid-Base Balance Test
Study Set
acid - Answer compound that forms H+ ions in solution
base - Answer compound that produces OH- ions in solution
as [H+] ___, pH ____ - Answer increases, decreases
normal arterial pH - Answer 7.4
-normal range: 7.35 to 7.45
acidosis - Answer pH < 7.35
alkalosis - Answer pH > 7.45
pH depends on...? - Answer [HCO3-] from kidney/PCO2 from lungs
-kidneys: metabolic, plasma HCO3-
-lungs: respiratory, pCO2
ratio of HCO3 to H2CO3 - Answer -20:1
-if H2CO3 increases, HCO3 must to maintain normal values
normal HCO3- - Answer 24mM
normal H2CO3 - Answer 1.2mM
acid base equation - Answer H2O + CO2
H2CO3
HCO3- + H+
how do kidneys produce HCO3-? - Answer 1. convert buffered acids into more acid salts
2. kidneys produce new HCO3 (glutamine = NH4 + HCO3)
where is HCO3 lost? - Answer -gut
-neutralizing of HCl
when is HCO3- production impacted? - Answer -when only 30% nephrons remain
-GFR drop by 70%
steps of HCO3 recycling in kidneys - Answer 1. Na from glomerular filtrate goes into
, tubular cell
2. H+ from tubular cell goes into glomerular filtrate
3. H+ and HCO3- in glomerular filtrate make H2CO3
4. H2CO3 dissociates into CO2 and H2O
5. H2O and CO2 go back into tubular cell, join to make H2CO3
6. H2CO3 dissociates into HCO3- and H+
7. HCO3- goes into plasma
stimulus to kidney altering HCO3- production - Answer 1. decrease in pH (acidosis) =
increase HCO3-
2. increase in pH (alkalosis) = decrease HCO3-
is renal compensation to pH change ST or LT? - Answer LT: days to weeks
stimulus to lungs altering pCO2 production - Answer 1. decrease in pH (acidosis) =
increase ventilation, decrease CO2
2. increase in pH (alkalosis) = decrease ventilation, increase CO2
is lung compensation to pH change ST or LT? - Answer ST: immediate
types of changes in blood pH - Answer metabolic OR respiratory
normal plasma HCO3- - Answer 22 to 28 mM
metabolic acidosis - Answer < 22 mM
-indicates deficit in base
-decreases pH
metabolic alkalosis - Answer > 28 mM
causes of metabolic acidosis - Answer -decreased renal HCO3- (e.g.: ARF, CRF, renal
deficits)
-loss of base from GI tract (e.g.: diarrhea)
-increased addition of fixed (e.g.: untreated DM, lactic acid in severe hypoxia)
MALA - Answer -metformin associated lactic acidosis
-metformin increases anaerobic metabolism and LA production
results of met acidosis - Answer -decreased brain function
Study Set
acid - Answer compound that forms H+ ions in solution
base - Answer compound that produces OH- ions in solution
as [H+] ___, pH ____ - Answer increases, decreases
normal arterial pH - Answer 7.4
-normal range: 7.35 to 7.45
acidosis - Answer pH < 7.35
alkalosis - Answer pH > 7.45
pH depends on...? - Answer [HCO3-] from kidney/PCO2 from lungs
-kidneys: metabolic, plasma HCO3-
-lungs: respiratory, pCO2
ratio of HCO3 to H2CO3 - Answer -20:1
-if H2CO3 increases, HCO3 must to maintain normal values
normal HCO3- - Answer 24mM
normal H2CO3 - Answer 1.2mM
acid base equation - Answer H2O + CO2
H2CO3
HCO3- + H+
how do kidneys produce HCO3-? - Answer 1. convert buffered acids into more acid salts
2. kidneys produce new HCO3 (glutamine = NH4 + HCO3)
where is HCO3 lost? - Answer -gut
-neutralizing of HCl
when is HCO3- production impacted? - Answer -when only 30% nephrons remain
-GFR drop by 70%
steps of HCO3 recycling in kidneys - Answer 1. Na from glomerular filtrate goes into
, tubular cell
2. H+ from tubular cell goes into glomerular filtrate
3. H+ and HCO3- in glomerular filtrate make H2CO3
4. H2CO3 dissociates into CO2 and H2O
5. H2O and CO2 go back into tubular cell, join to make H2CO3
6. H2CO3 dissociates into HCO3- and H+
7. HCO3- goes into plasma
stimulus to kidney altering HCO3- production - Answer 1. decrease in pH (acidosis) =
increase HCO3-
2. increase in pH (alkalosis) = decrease HCO3-
is renal compensation to pH change ST or LT? - Answer LT: days to weeks
stimulus to lungs altering pCO2 production - Answer 1. decrease in pH (acidosis) =
increase ventilation, decrease CO2
2. increase in pH (alkalosis) = decrease ventilation, increase CO2
is lung compensation to pH change ST or LT? - Answer ST: immediate
types of changes in blood pH - Answer metabolic OR respiratory
normal plasma HCO3- - Answer 22 to 28 mM
metabolic acidosis - Answer < 22 mM
-indicates deficit in base
-decreases pH
metabolic alkalosis - Answer > 28 mM
causes of metabolic acidosis - Answer -decreased renal HCO3- (e.g.: ARF, CRF, renal
deficits)
-loss of base from GI tract (e.g.: diarrhea)
-increased addition of fixed (e.g.: untreated DM, lactic acid in severe hypoxia)
MALA - Answer -metformin associated lactic acidosis
-metformin increases anaerobic metabolism and LA production
results of met acidosis - Answer -decreased brain function
