What are fluid requirements for healthy adults age 55-75?

• A. 25 ml/kg
• B. 30 ml/kg
• C. 35 ml/kg
• D. 40 ml/kg

Answer: (B)

Maintenance fluid needs for healthy adults are commonly estimated using body weight, with a practical baseline of about 30 ml per kilogram of body weight per day. This amount helps replace the daily losses from urine, stool, sweat, and respiration under typical conditions, while also recognizing that thirst sensation can be less reliable in older adults. For someone weighing 70 kg, that’s roughly 2.1 liters per day; for 60 kg about 1.8 liters; for 90 kg about 2.7 liters. In healthy adults aged 55–75, 30 ml/kg/day is a widely used starting point to ensure adequate hydration without pushing fluid balance toward overload, which can be a concern in aging kidneys or with cardiovascular issues. The other options either under- or over-shoot typical maintenance needs for this group, making 30 ml/kg/day the best general target.