Paediatric Clinical Guideline

Gastroenterology

11.5 Gastroenteritis

PAEDIATRIC PROTOCOL

GASTROINTESTINAL: 11.5

Dec 2006

Guidelines for Assessment and Management of Acute Gastroenteritis

Background return to the top

Infective gastroenteritis is characterised by rapid onset of diarrhoea, and is often accompanied by one of the following: nausea, vomiting, fever, anorexia, abdominal cramps, flatulence, or bloating. Acute symptoms last up to 14 days (PRODIGY Guideline, 2003, Dalby-Payne and Elliott, 2002). The commonest cause of most acute diarrhoea in children is gastroenteritis. In children under 5 years 80% ofmost episodes (80%) are contattrributable to viruses, with rotavirus being the most common. The principle organisms are Rota and Adeno-virus. Other enteric infections include other viruses, bacteria – (cCampylobacter, sSalmonella, sShigella, E-Coli) and, protozoa – (Giardia, amoebia)

The commonest cause of most acute diarrhoea in children is gastroenteritis. However, it is important froorm the history and examination to consider other possible diagnoses. Differential diagnosis for acute diarrhoea and vomiting in infants and children areinclude:

  • Systemic infection – UTI, pneumonia, sepsis
  • Surgical conditions – appendicitis, intussusception, sub acute bowel obstruction, Hirchsprung’s enterocolitis.
  • Other – Metabolic conditions such as diabetes mellitus, PKU, antibiotic diarrhoea, haemolytic uraemic syndrome.

If identified these conditions should be treated accordingly and this guideline is no longer appropriate.

History

As stated above, history and examination are important in establishing a diagnosis of acute gastroenteritis, the likely cause, and the level of dehydration, if any.

  • What are the on onset, sequence and duration of symptoms?
  • Are other family members or contacts (including pets) unwell?
  • Any recent foreign travel?
  • Has there been consumption of possible unsafe foods e.g. BBQ / take away?
  • Has the child visited any farms recently?
  • Any recent medication use (particularly antibiotics)?
  • Has the child had a recent weight? Any weight loss noted?
  • Any immunodeficiency known?

Document the number of episodes of vomiting and diarrhoea in the past two to three days, and the number of times the child has urinated in the last 24 hours, and d when the number of hours since last passed urine was last past. A child who is vomiting significant amounts more than 4 times a day, passing more than 8 stools, or who has urinated less than twice in that period is considered to be at higher risk and may warrant a period of observation (Armon, 2001).

Assessment of Dehydrationreturn to the top

Note:

The most accurate way is acute weight loss.

Clinical diagnosis of dehydration is difficult and often inaccurate. The accepted gold standard is acute weight loss but this is often not possible due to lack of accurate pre-illness weight.

A weight at presentation should be recorded at presentation and compared to any recent weight measurements.

Overall assessment is more accurate than looking at individual symptoms & signs.

  • Prolonged capillary refill time, abnormal skin turgor and absent tears have been shown to be the best individual examination measures. Dry mucous membranes can also be useful. If two out of four of these parameters are present the child has a high high likelihood ratiochance of being >5% dehydrated(Steiner MJ, 2004).
  • Dehydration in obese child is frequently under-estimated.
  • Young infants (< 3 months) may progress to shock much more rapidly than older children and adults.
  • It has been recommended that as a starting point it is helpful to use a general classification in terms of dehydration status as none, some (mild/moderate), or severe. (Cincinnati Children’s Hospital Medical Centre, 2002Guidelines).The following table should be used to help make an assessment of the degree of dehydration ordered in increasing severity

Clinical Sign / Mild
<5%No dehydration (<3% weight loss) / Mild - Moderate
35-10% / Severe
>10% / Notes
Reduced urine output / YesMild / Yes / Yes / Take care to differentiate urine from watery stool
Dry mouth / YesNo / Yes / Yes / Mouth breathers may always have dry mouth
Sunken fontanelle / No / Yes / Yes
Sunken eyes / No / Yes / Yes
Reduced skin turgor / No
(Recoils instantly) / Yes
(1-2 seconds) / Yes
(> 2 seconds) / May be less apparent in hypernatraemic dehydration (doughy skin)
Prolonged capillary
refill time / No / May be slightly prolongedYes / Yes cool/mottled/pale peripheries
Tachypnoea / No / Mild / YesMod / Increased with fever and metabolic acidosis
Tachycardia / No / Mild / YesMod / May be due to fever, irritability or hypovolaemia
Hypotension / No / No / YesPoss
Drowsiness/
Irritability / No / YesNo / YesSevere

Investigations return to the top

1) Stool culture is advised if the child attends day care or school so most patients will require one to be sent. If the history suggests a bacterial pathogen stool should also be sent. In mast cases Stool for virology, microscopy for ova, cysts and parasites and culture for bacteria will be sufficient but if the episode is prolonged (>14 days) three stools on subsequent days should be sent for ova, cysts and parasites also.

all children admitted with gastroenteritis

any child with prolonged diarrhoea > 7 days or blood in stool.

2) If dehydration is mild and differential diagnoses are excluded, no other investigations are required

3) If moderate to severe dehydration and they require NG / IV replacement blood tests may be helpful:

FBC

U&E

Creatinine

Bicarbonate level can be useful either from the lab or on a Ccapillary blood gas acid base

If temp >38.5 a Blood culture and FBC may be considered if temperature > 38.5

Fluid Management return to the top

Fluids should be prescribed at a volume which takes account of:

Maintenance fluid requirements

Fluid deficit (for aid to estimation of degree [%]of dehydration)

Ongoing losses

Maintenance fluid requirements

The daily fluid requirement may be estimated from the child's weight using the following formula:

1st 10kg of weight / 100mls/kg / 4mls/kg/hr
2nd 10kg of weight / 50mls/kg / 2mls/kg/hr
All additional kg of weight / 20mls/kg / 1ml/kg/hr

Example:

A 23 kg child will require

100mls/kg for the first 10kg / = 1000mls
50mls/kg for the second 10kg / = 500mls
20mls/kg for all additional Kg / = 60 mls
Total / = 1560mls
Rate / = 1560/24 = 65mls/hr

Fluid deficit

This estimate is calculated from the child's weight and the degree of dehydration which is estimated clinically. It is not calculated using the daily maintenance fluid requirement - a common error in correcting dehydration.

Example

A 23kg child who has reduced urine output, dry lips is assessed as being mildly dehydrated. His fluid deficit is estimated to be 5%.

23kg is equivalent to 23 litres. If he is 5% dehydrated his deficit is calculated using the formula:

23 x 0.05 = 1.15 litres = 1150mls

Note that this volume is significantly greater than if we had calculated 5% of his daily maintenance requirement.

It should be added to the total daily maintenance volume and divided by 24hrs

In our example

Maintenance 1560ml + 5% Deficit 1150ml = 2710ml over 24hrs = 112mls/hr

If you wish to replace the fluid deficit over a longer period (eg in hypernatraemic dehydration) then add the deficit to twice the daily maintenance and divide by 48hrs.

Ongiong Losses

These may be measured (eg stool or urine output, vomiting) or may be estimated (transdermal losses in fever or phototherapy).

One commonly used method where there are significant ongoing losses (eg high urine output, persistent vomiting, ileostomy losses, CSF drainage) is to measure the volume lost over 4hrs and replace it over the following 4hrs.

Criteria for Admission return to the top

Moderate or severe dehydration.

Mild dehydration who has failed to tolerate small volume (5ml) of oral fluid on a frequent basis (every 1-5 minutes) for short periods (1-2 hours).

Parents are not able to cope with rehydration at home.

Child at risk of rapidly developing severe dehydration or complications of their underlying diseases eg young infants < 3 months, short gut syndrome, child with ileostomy, congenital heart disease, chronic renal failure and metabolic disorders. The management of these children will need to be discussed with senior medical staff.

Drugs return to the top

The use of anti-emetics and antibiotics in general are not indicated in the management of gastroenteritis

Oral Rehydration Solution (ORS) return to the top

In UK, the two commonly used ORS are:

Dioralyte®, it contains 60 mmol of Na, 20 mmol K, 50 mmol CL, 10 mmol of citrate and 90 mmol of glucose per litre.

Rehidrat®, it contains 50 mmol of Na, 20 mmol K, 50 mmol CL, 20 mmol HCO3, 9 mmol of citrat, 91 mmol of glucose and 94 mmol sucrose per litre.

The following fluids may be given during an episode of mild to moderate gastroenteritis if ORS is not tolerated. They are diluted to reduce the concentration of sugar in them in order to prevent aggravation of the diarrhoea.

Solutions / Dilution in water
Cordial ( not low calorie) / 1 : 14
Carbonated Beverages (not low calorie) / 1 : 4 with warm water to remove bubbles
Unsweetened fruit juice / 1 in 4
Fruit juice drinks / 1 in 4

Managementreturn to the top

Feeding during gastroenteritis

  • Evidence supports the continuation or restarting of the child’s preferred, usual and age appropriate diet as soon as possible. This is particularly important in breastfed children. ( Sandhu et al, 1997)Armon, 2001,American Academy of Pediatrics, 1996, Cincinnati Children’s Hospital Medical Centre, 2002)

If the child is vomiting then very small, frequent feedings of normal diet or oral rehyrdration therapy (ORT) should be given. This may initially require theGet accurate initial weight

  • PParent / CCarer to to give small volume but frequent boluses of fluid eggive 5mls or 1 teaspoon aliquots every 1 to 5 minutes, gradually increaseincreasing the size of bolus once vomiting has settled (Armon, 2001).
  • Feed age appropriate food once dehydration is corrected. Regrading feed is not necessary. A Meta analysis of 16 studies found no significant advantage to diluting milk or formula in the management of acute gastroenteritis (Brown, 1994).
  • Regular diets may be supplemented with ORT with 10ml / kg for each stool or emesis.

Management if no signs of dehydration

If there are no signs of dehydration, and the child is not felt to be high risk (> 6 months and as listed above), advice can be given to continue at least maintenance fluids and to encourage a larger volume. Advice to be given to the carer can be found in the appendix, as can calculations for maintenance fluid. If the child is felt to be at higher risk a period of observation for a short period should be arranged.

If admitted consider using naso-gastric tube and admit the child who frequently vomits. Continuous naso gastric infusion is better than bolus in prevention of vomiting.

All but severe dehydration should be given a trial of oral rehydration

No dehydration / very mild dehydrationManagement of dehydration

Continue breast feeding.

No rehydration (ORS) required

Mild – Moderately dehydrationed (3 -3-10 5 %)

Oral rehydration therapy (ORT) should be used in all cases. Soft drinks alone are inappropriate and may cause osmotic diarrhoea (American Academy of Pediatrics, 1996).

  • 30-850ml/kg of ORTS plus continuing losses should be given over 4-6 hours (Armon, 2001, Cincinnati Children’s Hospital Medical Centre, 2002).
  • Those with milder dehydration, whose parents are able to cope, can continue rehydration at home after a short period of observation (1-2 hours).

If the child is breastfed, alternate normal feeds with ORT.

  • All mild – moderate cases should receive a trial of oral rehydration.

Feed age appropriate food once dehydration is corrected. Regrading feed is not necessary.MetaBrown, 1994)

Give extra fluid particularly if there is are large stool losses.

Diarrhoea and some vomiting may continue for a few more days, this is not worrying if child is tolerating most of the oral intake, passing urine and is alert.

If concerns return for reassessment and weighing.

Moderate dehydration Cincinnati Children’s Hospital Medical Centre, 2002

If oral rehydration is not sufficient or tolerated naso-gastric tube infusion of ORT should be given.

  • Naso-gastric tube infusion is preferred, as randomised controlled trials have shown this to be quicker and safer than intravenous therapy (Armon, 2001). There is no upper age limit to the use of an NG tube.
  • If IV fluids are felt to be necessary then either 0.9% saline or 0.45% saline and 5% glucose should be used.
  • Reassess every 6 hours until rehydrated.
  • Refeed once rehydrated, and after a further period of observation of 1-2 hours to ensure adequate intake, the child can be discharged if the carers are happy.
  • If ongoing rehydration is felt to be necessary, this should be continued, but the need for IV / NG should be reassessed. The child should be reviewed frequently aiming for discharge as soon as ongoing fluid requirements can safely be managed at home.

dehydration, whichOral rehydration given with 50-100ml/kg of ORS plus continuing losses over 4 to 6 hours.

Reassess every 3-4 hours including assessment of fluid requirement.

Accurate weight should be done every 6 hours until the child is rehydrated and then weigh daily until discharge.

Feed as soon as dehydration is corrected.

Severe dehydration with signs of circulatory collapse(a medical emergency)

Such a child will obviously require the input of a senior paediatrician early in their care, and once immediate resuscitation is complete, consideration about whether or not discussion with Paediatric Intensive Care is necessary.

NB. In the UK Itit is unusual for children with acute gastroenteritis alone to present in the UK with such severe dehydration and it is recommended that other diagnoses ought to be consideredshould be seriously considered.

  • Resuscitate immediately with 20 ml / kg of normal saline IV and reassess. This can be repeated if the child is still felt to be shocked. If a further fluid bolus is felt to be necessary an anaesthetist should be involved.
  • When resuscitation complete, consider admission to Paediatric Intensive CareIf post resuscitation, it is felt appropriate for the child to be managed on the general ward, further management can be followed as for moderate dehydration but obviously the child will require close observation, strict fluid balance and regular review. Electrolytes should be monitored closely every 2-3 hours to begin with.

potassium, which should be added to IV fluids once the child,Investigations for acute gastroenteritis

  • It is recommended that a sStool culture – should be be sent if:
  • the history suggests a bacterial pathogen i.e. blood in stool,
  • history suggestive of food poisoning or recent foreign travel (Armon, 2001)
  • . A stool should also be sent ifIf the diarrhoea is prolonged or the child is systemically unwell.

In most cases virology and culture for bacteria will be sufficient, but if the episode is prolonged (>14 days) three stools on subsequent days should be sent for ova, cysts and parasites. Laboratory testing may be done for pathogens not routinely sought, depending on information provided on the request form, so it is important this is sufficient.

  • Blood tests are usually not required.
  • If the child presents with:
  • severe dehydration with circulatory collapse
  • Uncertain diagnosis, if the diagnosis is not clear
  • blood in the stool
  • anuria/oliguria
  • recent contact with farm animals
  • , or if the child has a doughy feel to their skin which might suggest hypernatraemic dehydration then urea / creatinine, electrolytes, and bicarbonate should be requested.
  • If there is blood in the stool Aa blood culture and ffull blood count should be sent looking for microangiopathic haemolytic anaemia suggestive of Haemolytic Uraemic Syndromemay be considered.

Management of hypernatraemic dehydration (Na>150mmol/l) return to the top

  • This occurs in only 1% of admissions. It should be considered if there is a ‘doughy’ feel to the skin (Armon, 2001).
  • Avoid rapid correction as this may cause cerebral oedema, convulsion and death.
  • Aim for IV correction of deficit over 48 hours and a fall of serum Na concentration < 0.5 mmol/L per hour
  • 0.9% saline should be used to ensure the drop in saline is not too rapid.
  • Remember to also give maintenance and replace ongoing losses
  • 10 mmol KCL is added to 500ml IV fluid once urine is passed and hyperkalemia is excluded.
  • Repeat U&E every 4 hours until stable.

Prevention of Cross InfectionGeneral Issues

It is a statutory obligation to notify all cases of dysentery and suspected or confirmed food poisoning.

Parents and carers should be given advice on how to prevent transmission. A recent systematic review found that intervention to promote hand washing with soap reduced the risk of diarrhoeal disease by 47% (Curtis and Cairncross, 2003). Advice to carers should include

  • Personal hygiene with hand washing
  • Prompt disinfection of contaminated surfaces
  • Prompt washing of soiled clothes

A useful advice sheet, which covers this information and more, can be found at

Appendix 1

Calculation of maintenance fluid requirements

The daily fluid requirement may be estimated from the child's weight using the following formula:

1st 10kg of weight / 100mls/kg / 4mls/kg/hr
2nd 10kg of weight / 50mls/kg / 2mls/kg/hr
All additional kg of weight / 20mls/kg / 1ml/kg/hr

Example:

A 23 kg child will require

100mls/kg for the first 10kg / = 1000mls
50mls/kg for the second 10kg / = 500mls
20mls/kg for all additional Kg / = 60 mls
Total / = 1560mls
Rate / = 1560/24 = 65mls/hr

Calculation of fluid deficit

Fluid deficit in ml = % dehydration x weight (Kg) x 10

This estimate is calculated from the child's weight and the degree of dehydration, which is estimated clinically. It is not calculated using the daily maintenance fluid requirement - a common error in correcting dehydration.

Example:

A 23kg child who has reduced urine output, dry lips is assessed as being moderately dehydrated. His fluid deficit is estimated to be 5%.

23kg is equivalent to 23 litres. If he is 5% dehydrated his deficit is calculated using the formula:

23 x 0.05 = 1.15 litres = 1150mls

NB This volume is significantly greater than if we had calculated 5% of his daily maintenance requirement (a common mistake).

It should be added to the total daily maintenance volume and divided by 24hrs

In our example

Maintenance 1560ml + 5% Deficit 1150ml = 2710ml over 24hrs = 112mls/hr

If you wish to replace the fluid deficit over a longer period (e.g. in hypernatraemic dehydration) then add the deficit to twice the daily maintenance and divide by 48hrs.

Appendix 2

Drugs in acute gastroenteritis

Acute gastroenteritis is usually a self-limiting condition and drugs are not usually indicated.

Antimotility drugs

Antimotility drugs are not recommended in children under 4 years. There is limited data that Loperamide significantly reduces the time to relief from sysmptoms in older children however, it may lead to constipation and the routine use is not recommended. (ProdigyRODIGY guideline 2003)

Anti-emetics

There is some limited evidence that the use of Ondansetron or Metoclopramide over the use of placebo reduces the number of episodes of vomiting in children with gastroenteritis. There is however, an increased incidence of diarrhoea and concerns about the unacceptable levels of side effects (Alhashimi, 2006). The routine use in such patients is not recommended at present in the UK, and the decision to use should be that of a senior clinician.