358 Paediatric Emergencies
ABDOMINAL PAIN, DIARRHOEA AND VOMITING(ii) Causes in infants (up to 1 year)
(a) pyloric stenosis, typically in males aged 3–8 weeks presenting
with projectile vomiting
(b) infection: gastroenteritis, tonsillitis, otitis media, meningitis
and UTI
(c) intestinal obstruction from intussusception, an obstructed
hernia, etc.
(d) gastro-oesophageal reflux and hiatus hernia
(e) feeding problems secondary to overfeeding or excessive wind
(f) poisoning.
(iii) Causes after infancy
(a) infection: gastroenteritis, tonsillitis, otitis media, meningitis
and UTI
(b) intestinal obstruction or appendicitis
(c) metabolic, such as ketoacidosis or uraemia
(d) raised intracranial pressure or migraine
(e) poisoning.
4 Take a careful history, and recognize that not all vomiting and diarrhoea in
children is due to gastroenteritis. Features that indicate an alternative
diagnosis to ‘viral gastroenteritis’ include:
(i) Bloody diarrhoea.
(ii) Vomiting bile, blood or faecal material.
(iii) Systemic toxicity out of proportion to the degree of dehydration.
(iv) Severe abdominal pain with significant tenderness, distension or
a palpable mass.
5 Examine for evidence of an underlying cause and to determine the extent of
dehydration.
6 Assessment of dehydration
Regardless of the suspected cause, assess and treat dehydration in its own
right. Determine the degree of dehydration on clinical assessment by esti-
mated percentage change in body weight:
(i) Mild dehydration (up to 5% body weight lost): there are
no particular clinical signs and the child is in good general
condition, but with increased thirst and mild oliguria.
(ii) Moderate dehydration (6–10% body weight lost): the child looks
ill, is apathetic with sunken eyes and fontanelle, has a dry mouth,
decreased skin tissue turgor, tachycardia, marked thirst and oliguria.
(iii) Severe dehydration (10% or more body weight lost): the child
is drowsy, cool, cyanosed, tachypnoeic with deep acidotic
breathing, tachycardic, hypotensive and may become comatose.
There is a risk of sudden death.
7 Most children who can be orally rehydrated do not require blood tests.
(i) Send blood for FBC, U&Es, blood sugar and arterial or venous
blood gases in patients with moderate to severe dehydration.