What are fluid requirements for healthy adults age 18-55?

What are fluid requirements for healthy adults age 18-55?

• A. 20 ml/kg
• B. 25 ml/kg
• C. 35 ml/kg
• D. 45 ml/kg

Answer: (C)

Maintaining hydration in healthy adults relies on a maintenance fluid target of about 30–35 mL per kilogram of body weight per day. The upper end, 35 mL/kg/day, is a commonly cited value for daily maintenance in adults, reflecting normal insensible losses (skin and lungs) plus obligatory renal and gastrointestinal needs. For example, a 70 kg person would be around 2.4–2.5 liters of fluid per day (70 × 35). Values much lower than this (like 20 or 25 mL/kg/day) would under-hydrate most adults, while a much higher value (like 45 mL/kg/day) could lead to unnecessary fluid excess in someone with normal kidney and heart function. Adjustments are needed for fever, hot climates, high activity, or medical conditions that alter fluid balance.

Maintaining hydration in healthy adults relies on a maintenance fluid target of about 30–35 mL per kilogram of body weight per day. The upper end, 35 mL/kg/day, is a commonly cited value for daily maintenance in adults, reflecting normal insensible losses (skin and lungs) plus obligatory renal and gastrointestinal needs. For example, a 70 kg person would be around 2.4–2.5 liters of fluid per day (70 × 35). Values much lower than this (like 20 or 25 mL/kg/day) would under-hydrate most adults, while a much higher value (like 45 mL/kg/day) could lead to unnecessary fluid excess in someone with normal kidney and heart function. Adjustments are needed for fever, hot climates, high activity, or medical conditions that alter fluid balance.