How does the ionised calcium alter with changes in pH?

  • Ca2+ ions compete for binding sites on albumin with H+ ions
    • As pH changes the proportion of calcium bound to albumin and freely ionised in the plasma varies
    • For every 0.1 unit reduction in plasma pH, the albumin bound calcium decreases by 0.07 mmol/L and ionised calcium increases by 0.07 mmol/L