360 Paediatric Emergencies
ABDOMINAL PAIN, DIARRHOEA AND VOMITING(iv) For example, a 24 kg child has a daily fluid maintenance
requirement of:
(100 mL 10) + (50 mL 10) + (20 mL 4) = 1580 mL per 24 h.
4 Estimation of volume deficit
Base this on the estimated percentage dehydration (see earlier, p. 358) multi-
plied by the body weight, all multiplied by 10, that is:
Percentage dehydration body weight (kg) 10 in mL.
(i) For example, a 24 kg child considered to be 5% dehydrated has a
volume deficit of:
5 24 10 = 1200 mL.
(ii) Replace this fluid deficit over 24 h, if <5% dehydrated.
(iii) Give half the fluids over the first 8 hours and the remaining half
over the subsequent 16 hours, if >5% dehydrated and the sodium
is normal.
(iv) If the circulating volume has to be corrected in a shocked child
(see below), dehydration is then assumed to be 10%, giving a
maximum rehydration volume of 100 mL/kg.
5 Treatment of severe dehydration
Seek senior ED doctor help and refer the patient immediately to the paediatric
team.
(i) Give the shocked child 20 mL/kg normal saline i.v. (or
i.o.) boluses as fluid resuscitation, until the circulation and
hypoperfusion are restored.
(ii) Aim to then replace the fluid deficit and maintenance
requirements over 24 h with normal 0.9% saline in 5% dextrose,
if the sodium level is between 130 and 150 mmol/L and the
circulation is restored.
(iii) Replace fluid and electrolytes more slowly over 2–3 days, if the
sodium is <130 mmol/L or >150 mmol/L.
6 Treatment of moderate dehydration
Give rapid enteral (oral or nasogastric) rehydration with oral rehydrating
solutions such as Gastrolyte™ or Pedialyte™ over 4-6 h, in frequent small
amounts to replace the fluid deficit, and daily maintenance fluids over the fol-
lowing 18 h.
(i) Try oral rehydration following an antiemetic such as
ondansetron 0.1 mg/kg up to 4 mg orally.
(ii) Otherwise, rapid nasogastric rehydration is safe and effective in
most children even if the child is vomiting, as most children stop
this once NGT fluids are started:
(a) consider particularly if i.v. access will be challenging, e.g.
young chubby child
(b) commence NGT fluids at 25 mL/kg/h for the first 4 h.