This document provides guidelines for treating hypernatremia. It outlines three equations for calculating water deficit, estimating the effect of intravenous fluids on serum sodium concentration, and determining the rate of fluid administration. Common intravenous fluids and their sodium contents are listed. The recommended approach is to use the equations to determine the fluid and rate needed to lower the patient's serum sodium by no more than 10 mmol/L over 24 hours, while also replacing insensible water losses.

1. Treatment of
Hypernatremia
My Notes
By Dr Sahar Salem Sasy

2. Calculate the
 water deficit = Body weight (kg)x %of TBW x Serum Na /140 -1
% of TBW :
 Equation 1:
TBW = weight (kg) x correction factor
Correction factors
 Children: 0.6
 Nonelderly men: 0.6
 Nonelderly women: 0.5
 Elderly men: 0.5
 Elderly women: 0.45

3.  Estimate the effect of 1 L of any infusate on serum Na+
concentration as follow:
 Equation 2:
Change in serum Na+ = (infusate Na+ - serum Na+) ÷ (TBW + 1)
 Equation 3:
If the infusate contain Na and Ka use the following formula :
Change in serum Na+ = ([infusate Na+ + infusate K+} – serum Na+) ÷ (TBW + 1)
Equation 2 allows for the estimation of 1 L of any infusate on serum Na+
concentration. Equation 3 allows for the estimation of 1 L of any infusate
containing Na+ and K+ on serum Na+.

4. Common infusates and their Na+ contents include the following:
 5% dextrose in water (D5 W): 0 mmol/L
 0.2% sodium chloride in 5% dextrose in water (D5 2NS): 34 mmol/L
 0.45% sodium chloride in water (0.45NS): 77 mmol/L
 Ringer's lactate solution: 130 mmol/L
 0.9% sodium chloride in water (0.9NS): 154 mmol/L
The result will show how much Na will be reduced by 1L infusate (-x)

5. The rate will be calculated as follow :
10 ÷ (x) = (A1)L of solution is required The goal is to reduce the patient’s serum
sodium by no more than 10 mmol/L in a 24-hour period
(-x ) X 1000 (ml)=(A)ml to convert from L to ml.
Add the insensible water loss to calculate the total amount of fluid
required (ml or cc) per 24h.
A1+(1000 ml to 1500 ml insensible loss )=A2(ml)
A2 ÷ 24= A2 ml or cc /24h

6. All The Best