Randomised controlled trial of intravenous maintenance fluids

J Paediatr Child Health. 2009 Jan-Feb;45(1-2):9-14. doi: 10.1111/j.1440-1754.2007.01254.x. Epub 2007 Nov 25.


Aim: Traditional paediatric intravenous maintenance fluids are prescribed using hypotonic fluids and the weight-based 4:2:1 formula for administration rate. However, this may cause hyponatraemia in sick and post-operative children. We studied the effect of two types of intravenous maintenance fluid and two administration rates on plasma sodium concentration in intensive care patients.

Methods: A Factorial-design, double-blind, randomised controlled trial was used. We randomised 50 children with normal electrolytes without hypoglycaemia who needed intravenous maintenance fluids for >12 h to 0.9% saline (normal saline) or 4% dextrose and 0.18% saline (dextrose saline), at either the traditional maintenance fluid rate or 2/3 of that rate. The main outcome measure was change in plasma sodium from admission to 12-24 h later.

Results: Fifty patients (37 surgical) were enrolled. Plasma sodium fell in all groups: mean fall 2.3 (standard deviation 4.0) mmol/L. Fluid type (P = 0.0063) but not rate (P = 0.12) was significantly associated with fall in plasma sodium. Dextrose saline produced a greater fall in plasma sodium than normal saline: difference 3.0, 95% confidence interval 0.8-5.1 mmol/L. Full maintenance rate produced a greater fall in plasma sodium than restricted rate, but the difference was small and non-significant: 1.6 (-0.7, 3.9) mmol/L. Fluid type, but not rate, remained significant after adjustment for surgical status. One patient, receiving normal saline at restricted rate, developed asymptomatic hypoglycaemia.

Conclusion: Sick and post-operative children given dextrose saline at traditional maintenance rates are at risk of hyponatraemia.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adolescent
  • Child
  • Child, Preschool
  • Double-Blind Method
  • Fluid Therapy / adverse effects
  • Fluid Therapy / methods*
  • Glucose / administration & dosage*
  • Humans
  • Hyponatremia / blood
  • Hyponatremia / etiology
  • Hyponatremia / prevention & control
  • Hypotonic Solutions / administration & dosage
  • Infant
  • Infusions, Intravenous / methods
  • Intensive Care Units, Pediatric
  • Isotonic Solutions / administration & dosage
  • Postoperative Care / methods
  • Sodium / blood
  • Sodium Chloride / administration & dosage*
  • Treatment Outcome


  • Hypotonic Solutions
  • Isotonic Solutions
  • Sodium Chloride
  • Sodium
  • Glucose