In children fluids are supplemented during surgery to provide volume, to maintain blood glucose levels, electrolyte balance and to meet the ongoing fluid losses during surgery. Fluid replacement during surgery since decades has been based on the Holliday and Segar method.These authors proposed that water maintenance in children includes: 100 millilitre (ml)/100 kilocalorie (kcal) for the first 10 kg of body weight, 50mL/100 kcal for 11-20 kg and 20mL/100 kcal for every kilogram of body weight above 20 kg. The maintenance electrolyte requirements of 3 mEq/100 kcal for sodium and 2 mEq/100 kcal for potassium per day, were based upon the electrolyte composition of breast and cow's milk. Based on these recommendations hypotonic fluid (0.45% saline) was considered as the ideal fluid for maintenance in children undergoing surgery.