To determine how much hypertonic solution to give a patient with hyponatremia:
- calculate sodium deficit (mEq) = weight (kg) x 0.6 x (desired Na – actual Na)
- use 0.5 for females
- desired sodium in mEq/L
- calculate the safe rate of sodium correction for the patient in mEq/hr (0.5-1 mEq/L/hr) = weight (Kg) x 0.6 x 1.0 (rate of correction desired)
- 3% hypertonic saline contains 513 mEq/L; 2% contains 342 mEq/L; 1.5% contains 256 mEq/L and 0.9% contains 154 mEq/L
- desired rate = (safe rate of correction / 513) x 1000
- infusion time (hrs) = sodium deficit (mEq) / safe rate of correction (mEq/hr)
Marino: estimate initial infusion rate of 3% NaCl by multiplying patient’s KgBW by the desired rate of increase in plasma Na. Example: 70Kg male, desired rise in plasma is 0.5 mEq/L per hour, then infusion rate = 70×0.5 = 35 ml/Hr
Globalrph.com,. “Sodium Chloride 3% – Intravenous (IV) Dilution”. N.p., 2016. Web. 30 Jan. 2016.
Marino, 2014. The ICU Book.