102914 acid base disorders Flashcards
pCO2 can be correlated with
H+
normal pH is
7.4
life is sustained at what pH levels
6.8-7.6
where is most of the acid gotten rid of in the body?
lungs
how does the kidney buffer acid?
proximal tubule-bicarbonate is reabsorbed via actions of carbonic anhydrase
distal convoluted tubule-H ions are secreted into lumen
urine pH is
6-6.5
normal pCO2 is
40 mmHg
normal HCO3- is
24 mmol/L
respiratory acidosis is defined by values of?
pCO2 that are over 40 mmHg
metabolic alkalosis is defined by values of?
HCO3- that are over 24 mmol/L
systematic approach
pH
determine primary disorder (metabolic or respiratory)
calculate expected compensation
calculate anion gap
compensation for metabolic acidosis is calculated how
1.5 [HCO3-] + 8 = pCO2
or
last 2 digits of pH = pCO2 (this method works with pH down to 7.2)
compensation for metabolic alkalosis is calculated how
pCO2=0.9[HCO3-] + 9
in metabolic acidosis or alkalosis, pCO2 compensates in what direction in relation to bicarbonate level change?
same direction
compensation for respiratory acidosis is calculated how
acute: bicarbonate increases 1 mmol/L per 10mmHg increase in PaCO2
chronic: bicarbonate increases 4 mmol/L per 10 mmHg increase in PaCO2
compensation for respiratory alkalosis is calculated how?
acute: bicarbonate decreases 2 mmol/L per 10 mmHg decrease in PaCO2
chronic: bicarbonate decreases 4 mmol/L per 10 mmHg decrease in PaCO2
in respiratory acidosis or alkalosis, bicarb compensates in what direction in relation to changes in pCO2
same direction
what is the purpose of calculating compensation?
to determine if a secondary disorder is present
in a setting of a primary acid base disorder, what does compensation cause?
the setting of “normal” changes for the system is doing the compensation work
anion gap is normally equal to
10
anion gap equals
Na - (HCO3 + Cl)
what is considered appropriate compensation?
+/- 2
pH maintained by what?
pulmonary and renal buffering primarily
