Diarrhoea and Dehydration in Children: WHO Plans A, B and C

Diarrhoeal disease is one of the leading causes of death in children under 5 years worldwide, and a very common reason for paediatric visits in Pakistan. Most deaths are caused by dehydration and are preventable with oral rehydration solution (ORS), zinc and continued feeding. This summary follows the WHO approach.

Causes

• Viruses: rotavirus (now reduced by vaccination), norovirus and others.
• Bacteria: E. coli, Shigella (bloody diarrhoea), Campylobacter, Salmonella and Vibrio cholerae.
• Parasites: Giardia, Entamoeba and Cryptosporidium.

Risk factors:

• unsafe water
• poor sanitation and hygiene
• malnutrition
• not being breastfed
• incomplete vaccination

Types

• Acute watery diarrhoea (including cholera).
• Dysentery: blood in the stool.
• Persistent diarrhoea: lasting 14 days or more.

Assessing dehydration (WHO)

• Severe dehydration — two or more of:
  • lethargic or unconscious
  • sunken eyes
  • not able to drink, or drinking poorly
  • skin pinch goes back very slowly (2 seconds or more)
• Some dehydration — two or more of:
  • restless and irritable
  • sunken eyes
  • drinks eagerly, thirsty
  • skin pinch goes back slowly
• No dehydration — not enough signs to classify as some or severe.

Also look for:

• blood in the stool
• malnutrition
• fever
• other danger signs

Treatment plans (WHO)

Plan A — no dehydration (treat at home)

• Give extra fluids, including low-osmolarity ORS after each loose stool.
• Continue breastfeeding and normal feeding.
• Give zinc for 10–14 days: 10 mg daily under 6 months, 20 mg daily for 6 months and older.
• Teach the mother when to return:
  • not able to drink
  • becoming more unwell
  • fever
  • blood in the stool

Plan B — some dehydration (in a clinic)

• Give ORS about 75 mL/kg over 4 hours, in small frequent sips or spoonfuls.
• Reassess and continue feeding.
• Give zinc.

Plan C — severe dehydration (urgent)

• Start IV fluids immediately: Ringer's lactate (or normal saline), 100 mL/kg.
• Infants under 12 months: 30 mL/kg in 1 hour, then 70 mL/kg in 5 hours.
• Children 12 months and older: 30 mL/kg in 30 minutes, then 70 mL/kg in 2½ hours.
• Reassess frequently, and start ORS as soon as the child can drink.
• If IV access is impossible, give ORS by nasogastric tube while arranging referral.

Severe acute malnutrition needs a different rehydration approach, using special solutions and slower rates.

Other key points

• Antibiotics are not needed for most watery diarrhoea. Give them for dysentery (suspected Shigella; choose according to local resistance) and suspected cholera with severe dehydration.
• Do not give antidiarrhoeal drugs or antiemetics routinely to young children.
• Persistent diarrhoea needs nutritional assessment and investigation.
• Watch for complications:
  • electrolyte problems (low or high sodium, low potassium)
  • hypoglycaemia
  • kidney injury

Prevention

• Exclusive breastfeeding for the first 6 months.
• Safe drinking water.
• Hand washing with soap.
• Improved sanitation.
• Rotavirus and measles vaccination.
• Vitamin A supplementation where recommended.

Exam pearls

• Low-osmolarity ORS plus zinc is the cornerstone of treatment.
• Continue feeding during diarrhoea, including breastfeeding.
• Antibiotics only for dysentery and cholera; not for routine watery diarrhoea.

For more, see our Exam Night Rapid Revision Notes: Paediatrics 2.0.

Test yourself

5 exam-style single-best-answer questions. Choose your answer, then tap “Show answer”.

1. Child is lethargic, has sunken eyes, drinks poorly and skin pinch goes back very slowly. Classification?

   1. No dehydration
   2. Shock only
   3. Some dehydration
   4. Dysentery
   5. Severe dehydration
   Show answer

   Answer: E. Severe dehydration
   Two or more of these signs = severe dehydration (WHO Plan C).

2. WHO Plan B: how much ORS over 4 hours?

   1. 10 mL/kg
   2. None
   3. 200 mL/kg
   4. As much as the child wants only
   5. 75 mL/kg
   Show answer

   Answer: E. 75 mL/kg
   About 75 mL/kg of ORS over 4 hours for some dehydration.

3. Zinc dose for a 2-year-old with diarrhoea:

   1. 20 mg daily for 10–14 days
   2. 5 mg daily for 3 days
   3. 10 mg weekly
   4. 100 mg once
   5. Not recommended
   Show answer

   Answer: A. 20 mg daily for 10–14 days
   20 mg daily (10 mg under 6 months) for 10–14 days.

4. When are antibiotics indicated in childhood diarrhoea?

   1. Any fever
   2. Vomiting
   3. All watery diarrhoea
   4. Bloody diarrhoea (dysentery) or suspected cholera with severe dehydration
   5. Never
   Show answer

   Answer: D. Bloody diarrhoea (dysentery) or suspected cholera with severe dehydration
   Most watery diarrhoea is viral; antibiotics are for dysentery and cholera.

5. Plan C IV fluid for an infant under 12 months:

   1. Maintenance only
   2. 10 mL/kg once
   3. ORS only
   4. 30 mL/kg in 1 hour, then 70 mL/kg in 5 hours
   5. 100 mL/kg over 30 minutes
   Show answer

   Answer: D. 30 mL/kg in 1 hour, then 70 mL/kg in 5 hours
   Infants: 30 mL/kg in 1 hour then 70 mL/kg in 5 hours of Ringer's lactate.

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Disclaimer

For education and exam preparation only. This is not medical advice and must not be used to diagnose or treat patients. Always follow current clinical guidelines and the advice of qualified senior colleagues.