Requirements: Electrolytes

Sodium (Na )	1 mmol/kg/24 hours
Potassium (K )	0.5 mmol/kg/24hours

Therefore maintenance for average 70 kg adult

• 3 litre H O / 24 hr

• 80-100 mmol Na / 24hr

• 60 mmol K / 24hr

Common daily regimen for maintenance requirements (each litre is infused over eight hours or at 125 ml/hour)

• 1L 5% Dextrose + 20 mmol KCl

• 1L NaCl 0.9% + 20 mmol KCl

• 1L 5% Dextrose + 20 mmol KCl

Alternative daily regimen for maintenance requirements (each litre is infused over eight hours or at 125 ml/hour)

• 3L Solution 18 + 20 mmol KCl per litre

CAUTION with KCl

• Avoid concentration of $>$ 40 mmol/500 ml

• Avoid infusion rate of $>$ 15 mmol/hour

• Avoid potassium immediate post-op due to Cushing's response