From the Research
To calculate the milliequivalents (mEq) of sodium per liter in a 2% sodium solution, we need to convert the percentage concentration to mEq/L, which equals 870 mEq/L, as supported by the principles of chemistry and physiology 1, 2, 3, 4, 5.
Calculation
A 2% sodium solution contains 2 grams of sodium per 100 mL, which equals 20 grams per liter.
- Since sodium has an atomic weight of 23 g/mol and a valence of +1, one mole of sodium equals one equivalent.
- Therefore, 20 grams of sodium equals 20 ÷ 23 = 0.87 moles per liter.
- As each mole of sodium provides 1 equivalent, this equals 0.87 equivalents per liter, which is 870 mEq/L.
Clinical Context
This is an extremely high concentration of sodium compared to normal serum sodium levels of 135-145 mEq/L, as discussed in the context of treating hyponatremia 3, 4, 5.
- Such high concentrations would only be used in specific pharmaceutical preparations and would never be administered directly to patients without significant dilution, as it would cause severe electrolyte imbalances and potentially fatal consequences.
- The most recent and highest quality study on the treatment of severe hyponatremia supports the use of hypertonic saline solutions, but with careful consideration of the dose and administration route to avoid overcorrection 5.