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Intravenous Fluids

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These guidelines are not intended for:

  • use in Neonatal Intensive Care Units (NICU) or Special Care Baby Units/Nurseries (SCBU)
  • neurosurgical patients on specific neurosurgical fluid management protocols
  • paediatric oncology hydration fluid protocols


Specialist opinion should always be sought in the following situations:

  • Prematurity
  • Renal failure (including oliguric, polyuric or anuric)
  • Endocrine disturbances of electrolyte status
  • Known or suspected inborn errors of metabolism

Enteral rehydration and feeding is usually preferable and safer than IV fluids in children. The choice of enteral or IV fluids for a specific patient is outside the scope of this document.

Total parenteral nutrition administration and preparations are outside the scope of this document.

Standard intravenous fluids

1000ml bags should be prescribed whenever available

Where electrolytes are significantly outside the normal range, discuss with senior medical staff.

Resuscitation - all ages

10-20ml/kg boluses of 0.9% sodium chloride (or Plasma-Lyte 148 under specialist advice)
Maximum 1000ml per bolus

Use boluses in children with significant contraction of extracellular fluid volume or impending shock. See also sepsis and shock guidelines.

Resuscitation/bolus fluids DOs and DON'Ts

  • Do not use fluids with added glucose or potassium
  • Do not use starches
  • Do not use 4% albumin except under specialist advice

Maintenance and replacement fluids < 4 weeks corrected age

0.9% sodium chloride + 10% glucose + 20mmol/L potassium chloride†

Maintenance and replacement fluids ≥ 4 weeks corrected age

0.9% sodium chloride + 5% glucose + 20mmol/L potassium chloride†


Plasma-Lyte 148 + 5% glucose + 15mmol/L potassium chloride (already contains 5mmol/L of potassium chloride)

†See Maintenance fluid - when to prescribe Potassium.

Standard maintenance fluid rates (ml/hr)

In most circumstances use 70% maintenance. See exceptions.

100% maintenance is calculated using the 100/50/20 or 4/2/1 rule as per chart.

Maximum rate = 100ml/hr ie all children >60kg receive fluids as if they were 60kg.

These are indicative starting fluid rates only. These should be reassessed as clinically indicated and adjusted to the clinical situation.

Weight (kg) Infusion rate in ml/hr
  70% maintenance 100% maintenance 50% maintenance
4 11 16 8
5 14 20 10
6 17 24 12
7 20 28 14
8 22 32 16
9 25 36 18
10 28 40 20
12 31 44 22
14 34 48 24
16 36 52 26
20 42 60 30
30 49 70 35
40 56 80 40
50 63 90 45
60 and above 70 100 50

Exceptions to 70% maintenance rate

  1. 100% maintenance for children:
    1. Receiving  pre-operative fluids because they are nil by mouth (post-operative fluids should be calculated at 70%)
    2. With diarrhoea and vomiting
    3. With diabetic ketoacidosis
  2. 50% maintenance for children:
    1. With known or suspected meningitis, encephalitis or major head injury
    2. Intubated and cannot tolerate enteral feed
    3. With unexplained low serum sodium, pending investigations and confirmation of aetiology
    4. In whom hyponatraemia or respiratory distress develops or worsens despite being on 70% rate
  3. Children with inborn errors of metabolism - fluid rates and glucose concentration as per the metabolic team
  4. Children on dialysis or post renal transplant - fluid rates as per the renal team

Monitoring of fluid rate, electrolytes and glucose

All children who require IV fluids also require:

  • Immediately prior to administration of fluids:
    • Serum electrolytes (Na, K, urea, creatinine)
    • Glucose
  • Daily
    • Serum electrolytes (Na, K)
    • Accurate fluid balance with all intake and output recorded
    • Weight where feasible

Children with significant electrolyte or glucose abnormalities will need serum testing more often than daily. See relevant guidelines and seek senior medical advice.

  • Fluid rate should be reviewed frequently:
    • usually within 6 hours of commencement
    • at least daily
  • Fluids should be charted for no longer than 24 hours at a time (maximum)

Prescribing DOs and DON'Ts

  • Do prescribe the percentage sodium chloride (e.g. 0.9% sodium chloride, or 0.45%, or 0.225%)
  • Do not prescribe "normal saline", "N/S", "N/2" or variations on these
  • Do prescribe glucose, not dextrose
  • Do prescribe potassium chloride, not KCl
  • Do prescribe Plasma-Lyte 148, not P148

Delivery method DOs and DON'Ts

  • Do use an infusion pump for all children
  • Do clearly label additives as per standard labelling recommendations
  • Do use paediatric infusion sets with inline burette when intravenous additives (eg antibiotics) are being given. The burette must be filled with an appropriate amount of fluid and closed to the attached bag of fluid

Resuscitation/bolus fluids - notes

Starches have been shown in two well conducted randomised controlled trials to increase rates of renal failure in critically unwell adults2,3 and are expensive. They are not recommended for paediatric fluid administration.

4% Albumin is expensive, a pooled blood product and in limited supply. It may be harmful in head injured adults4. Use should be restricted to specialist advice.

Children with electrolyte abnormalities

Children with moderate-severe electrolyte abnormalities should be discussed with senior medical staff, and consider discussing severe abnormalities with a paediatric endocrinologist, nephrologist or intensivist.

0.9% sodium chloride containing fluids are suitable for non-severe cases of hyponatraemia and hypernatraemia.

0.45% sodium chloride containing fluids may be considered in special circumstances on senior medical advice. See 0.45% sodium chloride section below.

See hyperkalaemia guideline.

Maintenance fluid rate - notes

The standard maintenance formula (originally published by Holliday and Segar, and known as 100% maintenance, or the 100/50/20 or 4/2/1 rule) assumes that the majority of water losses are respiratory in origin. The original study did not include enough children to capture a good sample of those who have appropriate ADH secretion (children with intravascular volume depletion) or those with inappropriate ADH secretion (such as occurs commonly in those with pneumonia, meningitis, nausea, vomiting and pain, along with a myriad of other stimuli. Note that nausea and vomiting is a potent stimulus of ADH secretion and why hypotonic fluid in children with gastroenteritis frequently leads to hyponatraemia).

This guideline therefore recommends a rate of 70% of the standard maintenance formula in most circumstances.

The fluids recommended in this guideline at the 50% rate or above should not result in hypoglycaemia unless the patient has impaired glucose metabolism, as occurs in:

  • Liver failure
  • Severe sepsis and septic shock
  • Inborn errors of metabolism

Seek specialist advice when treating these patients, and for children who develop hypoglycaemia on restricted fluid volumes.

Maintenance fluid - when to prescribe Potassium

  • Fluids started in the emergency department generally do not require potassium (unless treating low potassium).
    • Only prescribe Potassium after serum potassium and creatinine results have been reviewed.
  • For patients receiving ongoing IV fluids on the ward, potassium should be added unless there is a high serum potassium or risk of (or known) renal impairment.
  • The standard amount of added potassium for most circumstances is 20mmol/L - this may be altered for individual patients.
  • Plasma-Lyte 148 + 5% glucose contains 5mmol/L potassium. If potassium addition is required, add 15mmol/L to bring the concentration to 20mmol/L.

Replacement of ongoing losses

The fluids used to replace patient losses should roughly match the electrolyte composition of the fluid being lost. In some cases, the lab may be able to analyse the fluid.

Gastrointestinal losses should be replaced in the first instance with 0.9% sodium chloride + 20mmol/L potassium chloride.

Standard ward fluids

Glucose 50% 500ml
Glucose 5% 1000ml
Glucose 10% 1000ml
Glucose 5% + Sodium chloride 0.9% 1000ml
Glucose 2.5% + Sodium chloride 0.45% 500ml
Plasma-Lyte 148 1000ml
Plasma-Lyte 148 in Glucose 5% 1000ml
Sodium chloride 0.9% 1000ml
Sodium chloride 0.9% + 20mmol/L KCl 1000ml

Additives to fluid bags

Use premade bags where possible.

Indication Prescription Use this

Resuscitation fluid

0.9% sodium chloride 1000mL bag 0.9% sodium chloride
Alternative under specialist advice Plasma-Lyte 148 1000mL bag of Plasma-Lyte 148
> 4 weeks corrected age maintenance  0.9% sodium chloride + 5% glucose 1000mL bag 0.9% sodium chloride + 5% glucose
0.9% sodium chloride + 5% glucose + 20mmol/L potassium chloride 1000mL bag 0.9% sodium chloride + 5% glucose and add 20mL of 10mmol/10mL potassium chloride
Alternative under specialist advice  Plasma-Lyte 148 + 5% glucose + 15mmol/L potassium chloride 1000mL bag Plasma-Lyte 148 + 5% glucose and add 15mL of 10mmol/10mL potassium chloride 
 < 4 weeks corrected age maintenance   0.9% sodium chloride + 10% glucose 1000mL bag 0.9% sodium chloride + 5% glucose and add 100mL 50% glucose 
0.9% sodium chloride + 10% glucose +20mmol/L potassium chloride  1000mL bag 0.9% sodium chloride + 5% glucose and add 100mL 50% glucose plus add 20mL of 10mmol/10mL potassium chloride
Ongoing fluid loss replacement  0.9% sodium chloride + 20mmol/L potassium chloride 1000mL bag 0.9% sodium chloride + 20mmol/L potassium chloride 

0.45% sodium chloride with additives

0.9% sodium chloride containing fluids are suitable for most clinical situations, however occasionally 0.45% sodium chloride is required on specialist advice. Instructions for making these are set out below:

Note: 0.45% sodium chloride is only available in 500ml bags

Indication Prescription Use this
>  4 weeks corrected age maintenance  0.45% sodium chloride + 5% glucose 500mL bag 0.45% sodium chloride + 2.5% glucose and add 25mL 50% glucose
0.45% sodium chloride + 5% glucose + 20mmol/L potassium chloride 500mL bag 0.45% sodium chloride + 2.5% glucose and add 25mL 50% glucose plus add 10mL of 10mmol/10mL of potassium chloride 
 < 4 weeks corrected age maintenance   0.45% sodium chloride + 10% glucose 500mL bag 0.45% sodium chloride + 2.5% glucose and add 75mL 50% glucose
0.45% sodium chloride + 10% glucose +  20mmol/L potassium chloride 500mL bag 0.45% sodium chloride + 2.5% glucose and add 75mL 50% glucose plus add 10mL of 10mmol/10mL of potassium chloride
  •   Adding 50ml of 50% glucose will increase the glucose concentration of:
    • 500ml bag of fluid by 5%
    • 1000ml bag of fluid by 2.5%
  • Highly concentrated sodium is available (labelled "4 molar sodium chloride", "23% sodium chloride" or "80 mmol sodium chloride in 20ml").  Addition of sodium chloride should be avoided - the calculations are provided for completeness.
Addition of 75mmol sodium chloride (=18.75ml of 4mmol/ml sodium chloride) to 1000ml bag will increase sodium concentration by 0.45%
Addition of 150mmol sodium chloride (=37.5ml of 4mmol/ml sodium chloride) to 1000ml bag will increase sodium concentration by 0.9%


The authors would like to acknowledge the following documents used as a basis for this guideline:

  • NSW KIDS + Families Standards for Paediatric IV Fluids, Second edition
  • Sick Children's Hospital Toronto Fluid and Electrolyte Administration In Children, Clinical Practice Guidelines
  • Royal Children's Hospital Melbourne, Clinical Practice Guidelines: IV Fluids - for children beyond the newborn period


  1. McNab S, Duke T, South M, Babl FE, Lee KJ, Arnup SJ, Young S, Turner H, Davidson A. 140 mmol/L of sodium versus 77 mmol/L of sodium in maintenance intravenous fluid therapy for children in hospital (PIMS): a randomised controlled double-blind trial. Lancet 2014;6736(14):1-8. doi:10.1016/S0140-6736(14)61459-8.
  2. Brunkhorst FM, Engel C, Bloos F, Meier-Hellmann A, Ragaller M, Weiler N, Moerer O, Gruendling M, Oppert M, Grond S, Olthoff D, Jaschinski U, John S, Rossaint R, Welte T, Schaefer M, Kern P, Kuhnt E, Kiehntopf M, Hartog C, et al. Intensive insulin therapy and pentastarch resuscitation in severe sepsis. N. Engl. J. Med. 2008;358(2):125-139. doi:10.1056/NEJMoa070716.
  3. Myburgh JA, Finfer S, Bellomo R, Billot L, Cass A, Gattas D, Glass P, Lipman J, Liu B, McArthur C, McGuinness S, Rajbhandari D, Taylor CB, Webb SAR. Hydroxyethyl starch or saline for fluid resuscitation in intensive care. N. Engl. J. Med. 2012;367(20):1901-11. doi:10.1056/NEJMoa1209759.
  4. Finfer S, Bellomo R, Boyce N, French J, Myburgh J, Norton R. A comparison of albumin and saline for fluid resuscitation in the intensive care unit. N. Engl. J. Med. 2004;350(22):2247-56. doi:10.1056/NEJMoa040232.
  5. Holliday MA, Segar WE. The maintenance need for water in parenteral fluid therapy. Pediatrics 1957;19(5):823-32. Available at: Accessed September 25, 2014.
  6. Moritz ML, Ayus JC. The changing pattern of hypernatremia in hospitalized children. Pediatrics 1999;104(3 Pt 1):435-439. doi:10.1542/peds.104.3.435.
  7. Hillier, T. A., Abbott, R. D., & Barrett, E. J. (1999). Hyponatremia: evaluating the correction factor for hyperglycemia. Am J Med, 106(4), 399-403.

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Document Control

  • Date last published: 18 May 2016
  • Document type: Clinical Guideline
  • Services responsible: ADHB Pharmacy, General Paediatrics, Paediatric Intensive Care Unit
  • Author(s): Brent McSharry, Greg Williams, Kaajal Dijkstra
  • Editor: Greg Williams
  • Review frequency: 2 years

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