Hypernatraemia

Clinical Features:

• Muscle weakness.
• Restlessness.
• Extreme thirst.
• Confusion.
• Lethargy.
• Irritability.
• Seizures.
• Unconsciousness.

Rx:

• Restriction of salt
  

1. inf.5%DA(1L)....I/V 10 drops/min

2. Inj.Lasix

• 2amp I/V stat...BD(8 am& 4 pm) if BP Normal

Formula for correction :

1) level of Na+

• 145-157mEq/L ➖ 24 hour
  
• 158-170 mEq/L➖ 48 hours
• 171-183 mEq/L➖ 72 hours
• 184-196 mEq/L➖ 84 hours

2) Any sign of shock :

• Correction by Normal saline bolus 20 ml/kg.Repeat if needed.

3) Solution contain Na+

• 3%Nacl ➖ 51mEq/L/100ml
  
• 0.9%Nacl➖15.4mEq/L/100ml
• 0.45%Nacl➖7.7mEq/L/100ml
• 0.25%Nacl➖3.8mEq/l/100ml

4)Formula:

Replacement Volume = 

FWD × 154/(154-conc.of Na+ Replacement Fluid)

NB: 

• 0.9Nacl ➖154mEq/L/1000ml
• 0.45%Nacl➖77mEq/L/1000ml

Free water deficit(FWD)=

( Current Na -145)/145 ×0.6 × weight

Exam: Newborn wt 3 kg & Na conc 160mEq/l

FWD=(160-145)/145 ×0.6×3=0.186

So,Replacement Fluid=

FDW× 154/(154-77)

=0.186×2

=0.372L 

So,372 ml 0.45% Nacl given in desired duration ( 48 hours) with maintain hence fluid.