Fluid Requirements in Adults

Method 1

Weight (kilogram [kg]) x 25-35 milliliter (mL)=mL fluid required daily:

  • 25 mL/kg for congestive heart failure or renal disease
  • 30 mL/kg for average adults
  • 35 mL/kg for patients with infection or draining wounds

Method 2

  • 1000 mL for the first 10 kg actual body weight
  • +50 mL fluid/kg for the next 10 kg actual body weight (or 1500 mL for the first 20 kg of body weight)
  • +15 mL fluid/kg for each additional kg over 20 kg (add this to the base of 1500 mL)

Method 3*

1 mL/kilocalorie of intake = mL fluid required daily

*If a patient’s calorie intake is poor, this method will underestimate fluid needs in many cases.

Method 4

(kg body weight – 20) x 15 +1500 = mL fluid required daily

Method 5

  • Average healthy adult: 30-35 mL/kg body weight
  • Adult 55-75 years: 30 mL/kg body weight
  • Adult >75 years: 25 mL/kg body weight

Dietary Reference Intakes: adequate intakes (AIs) for water

  • Adult males (>19 years): 3.7 liters (L)/day
  • Adult females (>19 years): 2.7 L/day

An increase or decrease in a patient’s fluid needs is based on a number of factors. Use clinical judgment to adjust fluid estimates as needed. The following factors can increase fluid requirements:

  • Fever
  • Nasogastric tube for suctioning
  • Fistula wound drains
  • Diarrhea
  • Vomiting
  • Hyperventilation
  • Respirator
  • Excessive perspiration
  • Pressure ulcer (stages II, III, IV)
  • Circulating air bed for wound-healing treatment

The following factors can decrease fluid requirements:

  • Congestive heart failure
  • Cardiac disease
  • Renal disease
  • Dilutional hyponatremia
  • Edema or ascites

References and recommended readings

Eckstein L, Adams K, eds. Pocket Resource for Nutrition Assessment. Chicago, IL: Dietetics in Health Care Communities Dietetic Practice Group, Academy of Nutrition and Dietetics; 2013.

Institute of Medicine of the National Academies; Panel on Dietary Reference Intakes for Electrolytes and Water, Standing Committee on the Scientific Evaluation of Dietary Reference Intakes, Food and Nutrition Board. Dietary Reference Intakes for Water, Potassium, Sodium, Chloride, and Sulfate.Washington, DC; National Academies Press; 2005. http://www.nal.usda.gov/fnic/DRI/DRI_Water/water_full_report.pdf. Accessed March 26, 2014. 

Mahan LK, Escott-Stump S, Raymond JL. Krause’s Food and the Nutrition Care Process. 13th ed. St Louis, MO: Elsevier Saunders; 2012.

Review Date: 
Saturday, March 1, 2014
Nutrition411 Staff