08 Acid Base Principles

• Equilibrium constantly in plasma
• pH at set point

• low bicarb, drive equation right, make more H, acidic

• don't memorize
• bicarb up, pCO2 down, increase pH
• bicarb down, pCO2 up, lower pH

• sample taken in arterial sys, radial a, for accurate pCO2

Acidosis

• blow CO2 off
• drop CO

• high CO2 = narcotic (people with pneumonia die painless death from high CO2 in older times)

Bohr effect:

• less saturation at any level
• H push O2 off hemoglobin
• O2 more easily leave

Alkalosis

• shift curve to left

Acid Base Problems

Examples

Compensation

• buffers prevent low pH from killing kidney

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• vomiting: alkalotic. Diarrhea: acidotic

Mixed Disorders

Metabolic Acidosis

• any kind of meta acidosis, compensation is respiratory alka

• simple metabolic acidosis with no secondary disorder

Metabolic Alkalosis

Respiratory acidosis

• acute: within minutes, intracellular buffer soaks up acid via hemoglobin, more HCO3

• low yield. Don't memorize

Respiratory alkalosis

• high altitude, respiratory alkalosis

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• special: respiratory acidosis and metabolic alkalosis or metabolic acidosis and alkalosis