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Clinical dehydration due to gastroenteritis — MRCEM SBA MCQ

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EasyPaediatric emergenciesClinical dehydration due to gastroenteritisMRCEM SBA

A 2-year-old child is brought to the emergency department after 24 hours of watery diarrhoea and two episodes of vomiting. She has passed less urine than usual. She is alert, with sunken eyes and dry mucous membranes, but has warm extremities, normal peripheral pulses and a capillary refill time of 2 seconds. She has not vomited for three hours. During an hour of supervised rehydration, she repeatedly refuses small, frequent offers of oral rehydration solution (ORS). What is the most appropriate next rehydration plan?

Educational content. Not a substitute for clinical judgement or local policy.

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Correct answer: C — Give nasogastric ORS, 50 ml/kg over 4 hours plus maintenance fluid.

Sunken eyes, dry mucous membranes and reduced urine output indicate clinical dehydration. Her alertness, warm extremities, normal pulses and capillary refill time do not suggest hypovolaemic shock. She needs rehydration, but intravenous resuscitation is not indicated. NICE recommends ORS for clinical dehydration, with 50 ml/kg for deficit replacement over four hours in addition to maintenance fluid. When a child cannot drink sufficient ORS, nasogastric administration should be considered, with regular clinical reassessment. ([nice.org.uk](https://www.nice.org.uk/guidance/cg84/chapter/Recommendations)) A gives the appropriate solution and volume, but repeating the oral approach does not address her refusal. B may appear efficient, but intravenous rehydration is not yet indicated: she is neither shocked nor deteriorating despite rehydration, and nasogastric ORS has not been tried. D is a shock-resuscitation bolus, not the next step for this well-perfused child. E addresses the route but omits replacement of the existing fluid deficit. If she subsequently deteriorates or persistently vomits ORS given orally or nasogastrically, the need for intravenous fluid should be reassessed. ([nice.org.uk](https://www.nice.org.uk/guidance/CG84/chapter/recommendations))

Reference: Diarrhoea and vomiting caused by gastroenteritis in under 5s: diagnosis and management — Recommendations (22 April 2009) — https://www.nice.org.uk/guidance/cg84/chapter/Recommendations Diarrhoea and vomiting caused by gastroenteritis in under 5s: diagnosis and management — Intravenous fluid therapy (22 April 2009) — https://www.nice.org.uk/guidance/CG84/chapter/recommendations Intravenous fluid therapy in children and young people in hospital — Clinical features of dehydration and hypovolaemic shock (December 2015) — https://www.nice.org.uk/guidance/ng29/chapter/recommendations