Which statement about insensible fluid losses is true?

Which statement about insensible fluid losses is true?

• A. They include urine output.
• B. They are approximately 10 mL/kg/day.
• C. They are exactly equal to 20 mL/kg/day.
• D. They are not measurable.

Answer: (B)

Insensible fluid losses are the fluid lost through the skin and via respiration that we can’t measure directly in a patient. Clinicians use an approximate value to guide maintenance fluids, with about 10 mL per kilogram per day being a common rule of thumb. This figure provides a practical benchmark because actual losses vary with fever, environment, ventilation, and other factors, so there isn’t a fixed number like 20 mL/kg/day. Urine output is a separate, measurable loss and not part of insensible losses. While insensible losses aren’t measured precisely, using the ~10 mL/kg/day estimate helps tailor fluid management in everyday practice.

Insensible fluid losses are the fluid lost through the skin and via respiration that we can’t measure directly in a patient. Clinicians use an approximate value to guide maintenance fluids, with about 10 mL per kilogram per day being a common rule of thumb. This figure provides a practical benchmark because actual losses vary with fever, environment, ventilation, and other factors, so there isn’t a fixed number like 20 mL/kg/day. Urine output is a separate, measurable loss and not part of insensible losses. While insensible losses aren’t measured precisely, using the ~10 mL/kg/day estimate helps tailor fluid management in everyday practice.