What is the minimum expected urine output for a child per hour?

• A. 0.5 mL/kg/hour
• B. At least 1 mL/kg/hour
• C. 2 mL/kg/hour
• D. 0.1 mL/kg/hour

Answer: (B)

Urine output per hour reflects how well the kidneys are filtering and how well circulating volume is being maintained. In children, a practical minimum target is at least 1 mL of urine per kilogram of body weight per hour. So, for a child weighing 20 kg, you’d expect about 20 mL of urine each hour at a minimum. This level indicates adequate renal perfusion and fluid status.

If urine output drops below that threshold, it can signal dehydration, reduced blood flow to the kidneys, or possible kidney dysfunction, and it calls for assessment and possible fluid adjustment or further evaluation. The other values aren’t used as the standard minimum: 2 mL/kg/hour is higher than necessary for the minimum, while 0.5 or 0.1 mL/kg/hour are too low to be considered acceptable minimums in most pediatric contexts.