Maintenance Fluid Regimen for Adults and Pediatric Patients
For pediatric patients, isotonic balanced solutions should be used as maintenance fluids, with volume calculated using the Holliday-Segar formula and restricted to 65-80% of calculated volume in patients at risk of increased ADH secretion.
Pediatric Maintenance Fluid Regimen
Fluid Type
- Use isotonic balanced solutions for maintenance fluid therapy 1
- Isotonic fluids significantly reduce the risk of hyponatremia compared to hypotonic solutions 1, 2
- Balanced solutions (containing buffers that replace some chloride with organic anions) are preferred over normal saline to reduce length of stay 1
- Avoid lactate buffer solutions in patients with severe liver dysfunction 1
Volume Calculation
- Calculate maintenance fluid volume using the Holliday-Segar formula 1:
- First 10 kg: 100 ml/kg/day (4 ml/kg/hour)
- Second 10 kg: 50 ml/kg/day (2 ml/kg/hour)
- Each additional kg: 25 ml/kg/day (1 ml/kg/hour)
Volume Restriction
- In acutely and critically ill children at risk of increased ADH secretion, restrict maintenance fluid volume to 65-80% of the calculated Holliday-Segar volume 1
- For children with heart failure, renal failure, or hepatic failure, restrict to 50-60% of calculated volume 1
- Consider all fluid sources in the total daily fluid intake calculation, including IV medications, blood products, arterial/venous line flush solutions, and enteral intake 1
Fluid Composition
- Include glucose in maintenance fluids to prevent hypoglycemia, guided by blood glucose monitoring 1
- Add appropriate potassium based on clinical status and regular monitoring 1
- Routine supplementation of magnesium, calcium, phosphate, vitamins, and trace elements is not recommended without evidence of deficiency 1
Adult Maintenance Fluid Regimen
While specific guidelines for adult maintenance fluids were not provided in the evidence, general principles include:
- Use isotonic balanced solutions
- Calculate volume based on weight, typically 30-35 ml/kg/day for adults
- Adjust based on clinical status, with restriction for patients with heart failure, renal failure, or conditions with increased ADH secretion
- Monitor electrolytes, especially sodium levels
Monitoring and Reassessment
- Reassess patients receiving maintenance fluids at least daily for fluid balance and clinical status 1
- Regularly monitor electrolytes, especially sodium levels 1
- Adjust fluid therapy based on clinical response and laboratory values
Special Considerations
- Enteral or oral route should be preferred for maintenance fluid therapy when tolerated 1
- Patients with increased risk of hyponatremia (postoperative state, CNS disorders, pulmonary disorders) require careful monitoring when receiving maintenance fluids 1
- Avoid fluid overload as it is associated with increased morbidity and mortality 3
Common Pitfalls to Avoid
- Using hypotonic solutions (like 0.2% or 0.45% saline) as maintenance fluids, which increases risk of hyponatremia 1, 2
- Failing to account for all sources of fluid intake, leading to "fluid creep" 1
- Not adjusting maintenance fluid rates in conditions with increased ADH secretion
- Inadequate monitoring of electrolytes, especially sodium
- Not recognizing signs of fluid overload or electrolyte disturbances
By following these evidence-based recommendations for maintenance fluid therapy, clinicians can optimize patient outcomes while minimizing the risks of hyponatremia, fluid overload, and other complications.