To calculate the amount of potassium supplement, one should have an estimate of the potassium deficit.
On average, a reduction of serum potassium by 0.3 mmol/l suggests a total body deficit of 100 mmol. Based on this formula, a patient with a serum potassium of 2.6 mmol/l needs at least 300 mmol of potassium for the correction of the deficit.
In calculating the total body potassium deficit one has to consider factors that can independently affect serum potassium. A patient with a serum potassium of 2.6 mmol/l has less total body deficit at blood pH of 7.5 than 7.3. The reason is that alkaline serum pH (that is, 7.5) can independently lower the serum potassium by intracellular shift.
 |
|
