What is the most appropriate maintenance fluid and infusion rate for a 13-year-old male post-appendectomy?

The most appropriate maintenance fluid for a 13-year-old male post-appendectomy is 5% dextrose and 1/4 normal saline at 95 mL/h.

In pediatric patients, maintenance fluid calculations are often based on the “4-2-1 rule," which helps determine the required hourly fluid intake based on weight. This technique involves administering 4 mL/kg/h for the first 10 kg of body weight, then 2 mL/kg/h for the next 10 kg, and finally 1 mL/kg/h for each kilogram over 20 kg.

For a 13-year-old, we assume a weight of perhaps around 40 kg. Using the 4-2-1 rule, the calculation would be:

• For the first 10 kg: 10 kg x 4 mL = 40 mL

• For the next 10 kg: 10 kg x 2 mL = 20 mL

• For the remaining 13 kg: 3 kg x 1 mL = 3 mL

Adding these together gives a total of 63 mL/h. Maintenance fluid is usually rounded to a common infusion rate, and 95 mL/h provides