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Gastroenteritis – Emergency

Gastroenteritis – Emergency management in children

Key points

  • Gastroenteritis is usually characterised by a sudden onset of diarrhoea, with or without vomiting, fever or abdominal pain
  • Management is primarily aimed at rehydration or prevention of dehydration.
  • Where possible, enteral methods of fluid administration are preferable to intravenous (IV).
  • Oral rehydration is effective in the majority of cases.


This document provides clinical guidance for all staff involved in the care and management of a child presenting to an Emergency Department (ED) with gastroenteritis in Queensland.

This guideline has been developed by senior ED clinicians and Paediatricians across Queensland and endorsed for statewide use by the Queensland Emergency Care of Children Working Group in partnership with the Queensland Emergency Department Strategic Advisory Panel and the Healthcare Improvement Unit, Clinical Excellence Queensland.


Acute gastroenteritis accounts for approximately 6.3% of emergency presentations in Australia and New Zealand.1 It is usually characterised by a sudden onset of diarrhoea, with or without vomiting, fever or abdominal pain.2 There is often a history of contact with another person with similar symptoms.

Viral pathogens including norovirus are responsible for approximately 70% of episodes of acute infectious diarrhoea in children.3,4,5 Bacterial infections (most commonly Campylobacter and Salmonella) account for approximately 15% of episodes.3,4

Dehydration can occur secondary to gastroenteritis. While untreated or poorly treated dehydration may be fatal, there are also risks associated with over-hydration and/or inappropriate electrolyte replacement, which can result in death from cerebral oedema.6

Hypernatraemia is a complication of gastroenteritis most commonly seen in infants less than one year of age, particularly those who have been given inappropriately concentrated formula or hyperosmolar home-made rehydration solutions, or in children who are unable to express the feeling of thirst and self-regulate fluid intake.7

Risk factors for dehydration

  • age less than one year, particularly pre-term infants and those less than six months
  • infants with low birth weight and failure to thrive
  • greater than five diarrhoeal stools in last 24 hours, especially in infants
  • stopped breast feeding during illness
  • signs of malnutrition
  • immunocompromised
  • underlying chronic medical conditions

Oral rehydration therapy

Acute gastroenteritis can often be managed effectively with oral rehydration therapy (ORT). This has been shown to reduce inpatient admissions when used in ED.8

Oral rehydration solutions use the principle of glucose-facilitated sodium transport whereby glucose enhances sodium and secondarily water transport across the mucosa of the upper intestine. Water absorption across the lumen of the gut is maximised when solutions with a sodium to glucose ratio of 1:1.4, and a sodium concentration of 60mmol/L are used.9 Appropriate rehydration solutions include Glucolyte, GastrolyteTM, HYDRAlyteTM and PedialyteTM.


The purpose of the assessment (history-taking and physical examination) is to:

  • confirm the diagnosis of gastroenteritis
  • understand extent of/potential for dehydration


History should include specific information on:

  • gastrointestinal symptoms (including date/time of onset, frequency, presence of blood in stools, bile stained vomiting, location and severity of abdominal pain)
  • other symptoms including fever, rash, headache
  • feeding
  • previous medical history
  • known illness in contacts


The aim of the physical examination is to assess hydration level, identify comorbidities and exclude other non-infectious causes of vomiting/diarrhoea. A careful assessment of conscious state and abdominal examination is required.

Hydration status

In the absence of the ability to accurately measure weight loss, a combination of clinical signs and symptoms are used to estimate the degree of dehydration.

Recognising the severity of dehydration (especially mild to moderate) can be challenging as parental report of vomiting, diarrhoea, and oral intake is unreliable6 and clinical signs can be imprecise and incorrect.3,10,11

  • Consider seeking senior emergency/paediatric advice as per local practice if uncertain of hydration status.
  • Seek senior emergency/paediatric advice as per local practice for a child in shock.
Hydration assessment
None Clinical dehydration
(5-10% fluid loss)
Clinical shock
(over 10% fluid loss)
Level of consciousness Alert and responsive Altered responsiveness Decreased level of consciousness
Skin colour Skin colour unchanged Skin colour unchanged Pale or mottled skin
Extremities Warm extremities Warm extremities Cold extremities
Eyes Eyes not sunken Sunken eyes Sunken eyes
Mucous membranes Moist mucous membranes Dry mucous membranes Dry mucous membranes
Heart rate HR normal HR normal Increased HR
Breathing RR normal Increased RR Increased RR
Peripheral pulses Peripheral pulses normal Normal peripheral pulses Weak peripheral pulses
Capillary refill Capillary refill normal Capillary refill normal Prolong capillary refill (greater than 2 seconds)
Skin turgor Skin turgor normal Decreased skin turgor Decreased skin turgor
Blood pressure BP normal BP normal Decreased BP (decompensated shock)
  • More numerous/pronounced symptoms and signs indicate greater severity.
  • For clinical shock, one or more of the symptoms or signs will be present.
  • If in doubt, manage as if dehydration falls into the more severe category.

Differential diagnoses

Differential diagnoses for child presenting with gastrointestinal symptoms
Surgical conditions Appendicitis, intussusception, bowel obstruction, malrotation with volvulus, strangulated hernia
Non-enteric infections Sepsis, UTI, meningitis, pneumonia, otitis media, other focal infections
Metabolic disease DKA and inborn errors of metabolism
Other Haemolytic uremic syndrome, inflammatory bowel disease, raised ICP

Red flags to suggest an alternative diagnosis

  • severe or localised abdominal pain
  • abdominal distension
  • isolated vomiting
  • bilious (green) vomit
  • blood in stool or vomit
  • child appears very unwell or is very drowsy
  • high grade fever – over 39℃ or 38.5℃ if aged less than three months
  • headache
  • rash

The very young infant and the malnourished child are more likely to have another diagnosis.

  • Consider seeking senior emergency/paediatric advice as per local practice if red flags are identified on assessment.


No investigations are routinely recommended. Tests to differentiate between bacterial and viral aetiology are not recommended as this will not influence management.

Other investigations may be considered based on possible alternative diagnoses.

Investigations that may be considered for children with gastroenteritis
Investigation type Indication
Blood glucose level Consider as part of initial assessment for children who are very lethargic or have had very little oral intake.
Biochemistry (Na+, K+, urea, creatinine, and glucose) and venous blood gas Consider for the following children:

  • require IV therapy
  • clinical suspicion of hypernatraemia (jittery movements, increased muscle tone, hyperflexia, convulsions, drowsiness or coma)
  • an altered level of consciousness
  • acute change in clinical condition
  • renal disease or taking diuretics
  • hyper or hypotonic fluids given orally at home
Point of care ketone testing Urinary or blood ketones can be used as a surrogate biochemical marker of a starvation state. Ketosis will also exacerbate nausea and vomiting. If available, may help guide decisions around the need/length of fluid trial/rehydration but should be used in conjunction with clinical picture.
Stool MCS Recommended for the following children:

  • suspected septicaemia
  • blood and/or mucous in stool
  • immunocompromised state

Consider for a child with a recent history of overseas travel, diarrhoea greater than seven days or uncertain gastroenteritis diagnosis.


Refer to flowchart for a summary of the emergency management for children presenting with symptoms of gastroenteritis.

Fluid management is the mainstay of therapy directed by the degree of hydration. Medication is not routinely recommended.2,6

Most children presenting to an ED with symptoms of gastroenteritis can be managed conservatively with an oral fluid trial as outlined below. For any child who requires nasogastric (NG) or IV rehydration, strict fluid balance must be recorded, with weighing of all nappies if relevant and at least daily weights.


Child in shock

  • Seek senior emergency/paediatric advice as per local practice for a child in shock.
  • Seek urgent paediatric critical care advice (onsite or via Retrieval Services Queensland (RSQ)) if signs of shock persist after two fluid boluses.
Fluid resuscitation for the management of shocked children
Bolus dose (IV or IO) Sodium Chloride 0.9% administered rapidly in 20 mL/kg bolus.
Repeat in 20 mL/kg boluses as clinically indicated.
Maintenance Fluid 100 mL/kg of Sodium Chloride 0.9% + Glucose 5% over next eight hours.
Reassess frequently and replace significant ongoing losses.
Rate may be revised on senior emergency/paediatric advice following identification of an electrolyte disturbance.
Consider sepsis in child with persisting signs of shock following fluid bolus.

Child with clinical signs of dehydration

In children with clinical signs of dehydration, the focus is on rehydration.

The most appropriate route of fluid administration (oral, NG or IV) is influenced by the age of the child and the severity of dehydration. Where possible enteral (NG and oral) rehydration is preferred (see Trial of fluids form) (QH only). In comparison with IV administration, enteral rehydration has been associated with better health outcomes (quicker return to normal diet, less vomiting and diarrhoea and improved weight gain at discharge), fewer complications, shorter hospital stay, and is more cost effective. NG rehydration is usually successful regardless of vomiting (though vomiting usually ceases following commencement of NG fluids). 3,12

Breastfeeding should always be continued throughout the rehydration phase.

Recommended routes of fluid administration for children with clinical signs of dehydration

  • Routinely recommended as initial route of choice for children with mild to moderate clinical dehydration.
  • Contraindicated in children with reduced level of consciousness (due to risk of aspiration) or ileus.

  • Consider for children aged less than two years:
    • with more severe dehydration
    • unable to tolerate oral rehydration (due to persistent vomiting/fluid refusal)
  • May be considered for older children but generally not well tolerated.
  • Contraindicated in children with reduced level of consciousness (due to risk of aspiration) or ileus.

  • Consider for children aged more than two years:
    • with more severe dehydration
    • unable to tolerate oral rehydration (due to persistent vomiting/fluid refusal)
  • Consider for children aged less than two years if NG fluids have failed.
Fluid administration for children with clinical signs of dehydration

  • Offer small amounts of oral rehydration solution (0.5 mL/kg) every five minutes via syringe/cup (better tolerated than larger volumes).13-16
  • Appropriate rehydration solutions include Glucolyte, GastrolyteTM, HYDRAlyteTM and PedialyteTM
  • Dilute apple juice, although not electrolyte replete, has been shown to have fewer treatment failures than oral rehydration solutions in mild gastroenteritis.17
  • Soft drinks and cordials should preferably not be used as rehydration fluid due to the minimal sodium content.

  • Rapid rehydration (50 mL/kg over 4 hours) using oral rehydration solution (NG) or Sodium Chloride 0.9% + Glucose 5% (IV) is routinely recommended.
  • Slower rate (over 8-12 hours) is recommended in children
    • with significant co-morbidities (e.g. renal disease, cardiac disease, diabetes, on diuretics)
    • infants less than 6 months of age to avoid fluid overload.
  • Replace significant losses to due to vomiting and diarrhoea (add volume loss to replacement and administer over next hour).

Regular reassessment is recommended. Rehydration therapy is regarded as successful if the clinical signs of dehydration have resolved.

Persistence of signs after four hours may be due to:

  • initial underestimation of the fluid deficit
  • persistent vomiting and/or diarrhoea
  • alternative/additional diagnosis

If signs of dehydration persist, further rehydration via NG or IV therapy is recommended. Consider testing for electrolyte abnormality.

  • Seek senior emergency/paediatric advice as per local practice if electrolyte abnormalities are identified on blood testing (as fluid adjustments may be required).

Feeding (using usual fluids) should be reintroduced after the acute phase of rehydration (two to four hours) or earlier if indicated by the child. Refer to Gastroenteritis Factsheet for further advice on feeding for parents/caregivers.

Child with no clinical signs of dehydration

In children with gastroenteritis without clinical signs of dehydration the focus is on prevention of dehydration.

Children should receive a fluid challenge with an oral rehydration solution at triage while awaiting medical assessment. Small amounts of oral rehydration solution (0.5 mL/kg) should be offered every five minutes via syringe/cup (better tolerated than larger volumes). See Trial of fluids form) (QH only).

Where relevant, breastfeeding should be encouraged.


A single dose of oral ondansetron is recommended to reduce vomiting.

Ondansetron has been shown to reduce the need for IV rehydration, rate of representation and length of hospital stay in children with gastroenteritis.

Ondansetron for the management of vomiting in children with gastroenteritis
Dose Given orally or sublingually at a dose of 0.15 mg/kg (maximum 8 mg).

Tablets and wafers are available in 4 mg and 8 mg doses. Recommended doses are as follows:

  • 8-15 kg: 2 mg
  • 15-30 kg: 4 mg
  • greater than 30 kg: 8 mg

Not recommended for children aged less than 6 months, weight less than 8 kg or with ileus.

Considerations Ondansetron prolongs the QT interval in a dose–dependent manner. Exercise caution in children who have or may develop prolongation of QTc (such as those with electrolyte disturbances, heart failure or on medications that may lead to a prolongation of the QTc).18,19


Antibiotics are not routinely recommended. Aetiology is commonly viral and there is no evidence of benefit and potential harm in uncomplicated bacterial gastroenteritis.

Antibiotic therapy is recommended for the following children:

  • suspected or confirmed septicaemia
  • Clostridium difficile-associated pseudomembranous enterocolitis
  • giardiasis, shigellosis, dysenteric amoebiasis or cholera

Consider antibiotic therapy for malnourished or immunocompromised children or infants aged less than six months with salmonellosis (refer to CHQ Non-typhoidal Salmonellosis in Children Guideline).

  • Seek senior emergency/paediatric advice as per local practice regarding antibiotic prescription.

Other medications

The following medications are not routinely recommended:

  • other anti-emetics including metoclopramide, prochlorperazine or dexamethasone – no evidence to support use and associated with significant side effects (e.g. dystonic reactions).
  • anti-diarrhoeal agents including Loperamide – associated with adverse consequences including lethargy, paralytic ileus, toxic mega-colon, CNS depression, coma and even death.

Escalation and advice outside of ED

Clinicians can contact the services below if escalation of care outside of senior clinicians within the ED is needed, as per local practices. Transfer is recommended if the child requires a higher level of care.

  • Critically unwell or rapidly deteriorating child

Includes children with the following (as a guide)
• persistent signs of shock despite two fluid boluses
• physiological triggers based on age (see below)

Less than 1 year 1-4 years 5-11 years Over 12 years
• RR >50
• HR <90 or >170
• sBP <65
• SpO2 <93% in oxygen or <85% in air
• GCS ≤12
• RR >40
• HR <80 or >160
• sBP <70
• SpO2 <93% in oxygen or <85% in air
• GCS ≤12
• RR >40
• HR <70 or >150
• sBP <75
• SpO2 <93% in oxygen or <85% in air
• GCS ≤12
• RR >30
• HR <50 or >130
• sBP <85
• SpO2 <93% in oxygen or <85% in air
• GCS ≤12
Reason for contact Who to contact
For immediate onsite assistance including airway management The most senior resources available onsite at the time as per local practices.
Options may include:

  • paediatric critical care
  • critical care
  • anaesthetics
  • paediatrics
  • Senior Medical Officer (or similar)
Paediatric critical care advice and assistance Onsite or via Retrieval Services Queensland (RSQ).
If no onsite paediatric critical care service contact RSQ on 1300 799 127:

  • for access to paediatric critical care telephone advice
  • to coordinate the retrieval of a critically unwell child

RSQ (access via QH intranet)
Notify early of child potentially requiring transfer.
Consider early involvement of local paediatric/critical care service.
In the event of retrieval, inform your local paediatric service.

  • Non-critical child

Reason for contact Who to contact
(including management, disposition or
Follow local practices. Options:

  • onsite/local paediatric service
  • Queensland Children’s Hospital experts via Children’s Advice and Transport Coordination Hub (CATCH) on 13 CATCH (13 22 82)
    (24-hour service)
  • local and regional paediatric videoconference support via Telehealth Emergency Management Support Unit TEMSU (access via QH intranet) on 1800 11 44 14 (24-hour service)
Referral First point of call is the onsite/local paediatric service

Inter-hospital transfers

Do I need a critical transfer?
Request a non-critical inter-hospital transfer
Non-critical transfer forms


When to consider discharge from ED

The majority of children with gastroenteritis who present with no or mild signs of clinical dehydration can be safely discharged home following a short period of observation.

Consider discharge for the following children:

  • no signs of clinical dehydration
  • demonstrated capacity to maintain hydration during trial of oral fluids
  • parents/caregivers received education regarding management at home
  • alternate diagnoses considered and excluded

A longer period of observation in SSU or inpatient service may be considered for children with risk factors for dehydration including children aged less than one year especially if pre-term or failure to thrive, signs of malnutrition, immunocompromised or other underlying chronic medical conditions.

On discharge, parents/caregivers should be provided with a Gastroenteritis Factsheet.


With GP if symptoms worsen or persist after two to three days.

When to consider admission

Admission to an inpatient service or SSU (where relevant) is recommended for the following children:

  • require NG or IV rehydration
  • concerns regarding ability to maintain adequate hydration at home

Related documents



  1. Acworth J., Babl F., Borland M., et al. Patterns of presentations to the Australian and New Zealand paediatric emergency research network. Emergency Medicine Australasia. 2009; 21 (1): 59-66.
  2. Heinz P. Management of acute gastroenteritis in children. Paediatrics and Child Health. 2008; 18 (10): 453-457.
  3. Elliott EJ., Dalby-Payne JR. Acute infectious diarrhoea and dehydration in children. Medical Journal of Australia. 2004; 181 (10): 565-570.
  4. Webb A., Starr M. Acute gastroenteritis in children. Australian Family Physician. 2005; 35 (4): 227-231.
  5. KooHL.,Nei FH,EsteslMK.,Norovirus:the most common pediatric viral enteri pathogenat a large university teaching hospital after introduction of rotavirus vaccination. Journal of Pediatric Infectious Diseases Society. August 3,2012
  6. Canavan A., Arant BS. Diagnosis and management of dehydration in children. American Family Physician. 2009; 80 (7): 692-696.
  7. Moritz ML., Ayus JC. The changing pattern of hypernatraemia in hospitalised children. Pediatrics. 1999; 104 (3): 435-439.
  8. Boyd R., Busuttil M., Stuart P. Pilot study of a paediatric emergency department oral rehydration protocol. Emergency Medicine Journal. 2005; 22 (2): 116-117.
  9. Reeves JJ., Shannon MW., Fleisher GR. Ondansetron decreases vomiting associated with acute gastroenteritis: a randomized, controlled trial. Paediatrics. 2002; 62, 109.
  10. Gorelick MH., Shaw KN., Murph KO. Validity and reliability of clinical signs in the diagnosis of dehydration in children. Pediatrics. 1997; 99 (5): 724.
  11. Steiner MJ., DeWalt DA., Byerley JS. Is this child dehydrated?. The Journal of the American Medical Association. 2004; 291 (22): 2746-2754.
  12. Nazarian LF., Berman JH., Brown G., et al. Practice parameter: The management of acute gastroenteritis in young children. Pediatrics. 1996; 97 (3):424-435.
  13. Levy JA.,Waltzman,MD.,Monuteaux,ScD,Bachur RD. Value of point of care ketones in assessing dehydration and acidosis in children with gastroenteritis. Academic Emergency Medicine 2013;20:1146-1150
  14. World Health Organisation. The treatment of diarrhoea: A manual for physicians and other senior health workers [internet]. Geneva: World Health Organisation; 1995 [cited 2011 May 9]. Available from:
  15. Centre for Disease Control and Prevention. Managing acute gastroenteritis among children: Oral rehydration, maintenance, and nutritional therapy [internet].  Atlanta (GA): Centre for Disease Control and Prevention; 2003 [cited 2011 May 9]. Available from:
  16. Freedman SB., Adler M., Seshadri R., et al. Oral ondansetron for gastroenteritis in a paediatric emergency department. The New England Journal of Medicine. 2006; 354 (16): 1698-705.
  17. Freedman SB., Willan AR., Boutis K., Schuh S. Effect of Dilute Apple Juice and Preferred Fluids vs Electrolyte Maintenance Solution on Treatment Failure Among Children with Mild Gastroenteritis. Journal of the American Medical Association. 2016, 315 (18): 1966-1974
  18. National Institute for Health and Care Excellence NICE) Evidence summary: Management of vomiting in young people and children with gastroenteritis: ondansetron Published 07 Oct 2014
  19. Ondansetron for Intravenous Use: dose-dependent QT interval prolongation: new posology. Drug Safety Update Volume 6, Issue 12, July 2013

Guideline approval

Guideline approval history
Document ID CHQ-GDL-60015 Version no. 3.0 Approval date 17/12/2020
Executive sponsor Executive Director Medical Services Effective date 17/12/2020
Author/custodian Queensland Emergency Care Children Working Group Review date 26/09/2022
Supersedes 2.0
Applicable to Queensland Health medical and nursing staff
Document source Internal (QHEPS) + External
Authorisation Executive Director Clinical Services QCH
Keywords Gastro, gastroenteritis, diarrhoea, paediatric, emergency, guideline, children, 60015
Accreditation references NSQHS Standards (1-8): 1 Clinical Governance, 4 Medication Safety, 8 Recognising and Responding to Acute Deterioration
ISO 9001:2015 Quality Management Systems: (4-10)


This guideline is intended as a guide and provided for information purposes only. View full disclaimer.
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