Proper evaluation of serum calcium level requires estimation of:: (A) Serum potassium, (B) Serum phosphorus, (C) Serum albumin, (D) Urinary output
Answer is C. Concentration of serum protein especially serum albumin is an impoant determinant of calcium ion concentration. Calcium is mostly bound to serum albumin. % of protein bound calcium = 0.8 x albumin (g/l) + 0.2 x globulin (gll) + 3. This formula is used for calculation of calcium bound to proteins. A rough formula is to add 1 mg/dl, to the serum calcium level for every l g/dl, by which serum albumin level is below 4 g/dL.