Paediatric Emergencies 359
ABDOMINAL PAIN, DIARRHOEA AND VOMITING
8 Send urine for microscopy, culture and sensitivity if significantly
dehydrated, febrile or in pre-school children with unexplained vomiting.
9 Collect a faecal sample only if the child has significant abdominal pain,
persistent bloody diarrhoea or a history of recent overseas travel.
10 Order CXR and abdominal X-ray (AXR) if there is clinical evidence of respi-
ratory tract infection or intestinal obstruction.
MANAGEMENT
1 The aims of management are to:
(i) Restore and maintain fluid and electrolyte balance.
(ii) Restore nutrition.
(iii) Replace ongoing losses (diarrhoea and vomiting).
2 Calculate the total amount of f luid needed over the next 24 h by adding
together maintenance f luid requirements, estimated volume deficit and
ongoing losses (see Table 11.5).
3 Maintenance fluid requirements
These are:
(i) 100 mL/kg per 24 h for the first 10 kg of body weight (4 mL/kg
per h).
(ii) 50 mL/kg per 24 h for the next 10 kg of body weight (2 mL/kg per h).
(iii) 20 mL/kg per 24 h for each remaining kg of body weight (1 mL/
kg per h).
Table 11.5 Paediatric fluid and electrolyte requirements
Body weight Fluid maintenance
mL/kg per hour mL/kg per day
First 10 kg 4 100
Second 10 kg 2 50
Each subsequent kg 1 20
Potassium: maintenance 3 mmol/kg per 24 hours
Fluid resuscitation: bolus 20 mL/kg crystalloid
Deficit volume: estimation in % body weight dehydration × weight
dehydration (mL) (kg) × 10
Burns: additional fluid % BSA burn × weight (kg) × 4
requirement (mL per day)
Urine output: intended Infants (<2 years): 2 mL/kg per hour
Children (>2 years): 1 mL/kg per hour
BSA, body surface area.