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Maintenance Fluid Calculator

Calculate daily maintenance fluid requirements for dogs and cats based on weight and condition.

Maintenance Fluid Guidelines

Standard Calculation Methods:

  • Weight-based method: 2-3 ml/kg/hr or 40-60 ml/kg/day
  • Body surface area method:
    • For the first 10 kg: 4 ml/kg/hr
    • For the second 10 kg: add 2 ml/kg/hr
    • For each kg over 20 kg: add 1 ml/kg/hr

Adjustment Factors:

  • Reduce by 25-50% for patients with cardiac disease or renal failure
  • Increase by 25-50% for patients with fever, hyperthermia, or increased respiratory losses
  • Adjust based on ongoing monitoring of hydration status, urine output, and electrolyte balance

Common Maintenance Fluids:

  • Lactated Ringer's Solution
  • Normosol-R
  • Plasma-Lyte
  • 0.9% NaCl (use with caution for long-term maintenance)
  • 0.45% NaCl with 2.5% dextrose (for cats)