Acid-Base Flashcards
Volatile vs fixed acids
Volatile - exhaled (CO2)
Fixed - not exhaled (lactic, sulfuric, ingested, etc.)
pH values for acidosis and alkalosis
Acidsosis < 7.2
Basic > 7.6
Intercellular buffers
Bicarb and phosphate
Respiratory alkalosis
PCO2 is below 40, HCO3- is normal
Respiratory acidosis
PCO2 is above 40
HCO3- is normal
Metabolic alkalosis
PCO2 is normal
HCO3- is above 28
Metabolic acidosis
PCO2 is normal
HCO3- is below 18
How does pH change for every 10mm increase/decrease in CO2?
10mm CO2 increase = .08 pH decrease
Acidosis/acidemia and alkalosis/alkalemia
Acidosis < 7.35 (more common, body tends toward this)
Alkalosis > 7.45
Buffers in the body
Bicarb (primary) Phosphate Plasma proteins (albumin) Hgb ATP 2-3 DPG
Carpal pedal spasm
Hyperventilation leads to hypocalcemia leads to spasming of extremities
Anion gap
Use to differentiate b/w types of metabolic acidosis
Normal - 8-16
High = acid overproduction (too much + charge)
Low = likely hypoalbuminea
Normal = likely low bicarb and Cl- is being held onto to compensate for ionic difference
How do we maintain a constant pH?
Use of buffers (adjusts w/in seconds)
Respiration (adjusts w/in minutes)
Renal excretion of H+ and reabsorption/production of HCO3- (adjusts w/in hours or days)
What is the equilibrium constant (pKa)?
The pH where an acid or base is 50% associated (HA/BH+) and 50% disassociated (A-/B)
How does the kidney maintain pH?
Reabsorption of HCO3- in proximal tubule
Excreting fixed acids (NH4, etc.)
Secretion of H+
Making HCO3-
