Compensation

Explain the principles underlying acid-base chemistry

Metabolic Acidosis

Compensation to metabolic acidosis includes:

• Buffering
  Occurs over minutes to hours. Includes:
  • ECF buffers
    • Bicarbonate
    • Plasma proteins
      • Albumin
  • ICF buffers
    • Include phosphate, proteins
    • Leads to hyperkalaemia due to H⁺/K⁺ exchange
      K⁺ increases by 0.6mmol.L^-1 per 0.1 unit fall in pH.
  • Bone
    Exchange of Na⁺ and Ca²⁺ in bone.
    • Leads to demineralisation and release of alkaline compounds
• Respiratory compensation
  Occurs in minutes.
  • Rapid response
  • Cannot compensate completely
• Renal compensation
  Occurs over days to weeks. Includes:
  • Elimination of H⁺ bound to filtered buffers
    • Include ammonium, phosphate
  • Reabsorption of bicarbonate
  • Active secretion of H⁺ in the DCT/CT
    Under control of aldosterone.

References

1. Diaz, A. Describe how the body handles metabolic acidosis. Primary SAQs.