Holliday-Segar Fluid Requirement

How to use it

1. 1

   100/50/20 rule (per day). 0–10 kg: 100 mL/kg/day. 10–20 kg: add 50 mL/kg/day. > 20 kg: add 20 mL/kg/day.

2. 2

   4-2-1 rule (per hour). Divide by 24 or use: 4/2/1 mL/kg/h for each weight band.

3. 3

   Adjust for deficits and ongoing losses. Vomiting, diarrhoea, pyrexia: add replacement on top of maintenance.

When to use it

Paediatric IV fluid prescription

Isotonic fluid (0.9% NaCl or Hartmann) preferred over 0.45% to avoid hyponatraemia.

Nil by mouth perioperatively

Maintain IV maintenance during prolonged fasting.

Fluid resuscitation (not maintenance)

Shock: 10–20 mL/kg bolus crystalloid, repeated as needed — separate from maintenance.