An 8 kg infant with diarrhoea at a health house 90 minutes from hospital
A 10-month-old boy weighing 8.0 kg is brought to a rural health house at 19:00 with three days of watery diarrhoea (seven to eight stools a day, no blood) and vomiting after feeds since this morning. He weighed 8.6 kg three weeks ago. He is irritable but consolable, with sunken eyes, a skin pinch that returns in about 3 seconds, dry mucous membranes, and he has passed no urine for eight hours. Axillary temperature 38.4 °C, heart rate 148/min, respiratory rate 44/min, capillary refill 3 seconds, and the anterior fontanelle is slightly sunken. He is still able to drink. The nearest hospital with paediatric admission is 90 minutes away by car; the health house has oral rehydration salts, zinc tablets and no intravenous fluids. The mother stopped breastfeeding during the illness because she believed milk worsened the diarrhoea.
1. Classify his dehydration with justification, then write the exact rehydration plan you start now with the supplies available, including volumes and the reassessment point.
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Classification: some dehydration (WHO Plan B), with warning features. He has two or more of the WHO signs for some dehydration: sunken eyes, a skin pinch returning in about 3 seconds, restlessness and irritability, and he drinks eagerly. He does not meet severe dehydration criteria: he is not lethargic or unconscious, he is able to drink, and the skin pinch is slow but not very slow (2 seconds or more with extreme slowness). The 3-second capillary refill and 8 hours without urine mean he must be watched closely, but they do not justify intravenous therapy, which is not available in any case.
Plan B now: oral rehydration solution 75 mL/kg over 4 hours = 600 mL, given by cup and spoon in small frequent sips, about 25 mL every 10 minutes, continuing breastfeeding on demand between sips. If he vomits, wait 10 minutes and resume more slowly. Give zinc 20 mg immediately (see below).
Reassess at 1 hour and at 4 hours, or sooner if he deteriorates, using the same four signs plus weight, heart rate and urine output. If he improves, switch to Plan A: 50-100 mL of ORS after each loose stool for a child under 2 years, plus continued feeding. If he develops severe dehydration signs (lethargy, unable to drink, very slow skin pinch), he needs Plan C: Ringer lactate 100 mL/kg, 30 mL/kg in the first hour and 70 mL/kg over the next 5 hours in a child under 12 months, which means immediate referral down the 90-minute road rather than continuing oral therapy.
2. What drugs and feeding advice do you add, and when would you give an antibiotic?
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Zinc: 20 mg of elemental zinc daily for 10-14 days (10 mg if under 6 months). This shortens the diarrhoea, reduces stool volume and prevents recurrence in the following months. Give the first dose today.
No antibiotic for this episode. Acute watery diarrhoea without blood is usually viral and antibiotics do not help. Reserve antibiotics for: gross blood in the stool with fever and tenesmus (dysentery, treat with ciprofloxacin or ceftriaxone according to local resistance), suspected cholera with profuse rice-water stools and rapid dehydration (doxycycline or azithromycin per national protocol), or a proven specific pathogen. Also avoid antidiarrhoeals such as loperamide (dangerous in children), adsorbents, and routine antiemetics; a single dose of ondansetron may be considered if vomiting prevents oral rehydration, but it is not needed here.
Feeding: continue breastfeeding throughout and after rehydration; the mother should be told explicitly that breast milk does not worsen diarrhoea and that stopping it removes the safest fluid and nutrition he has. Continue age-appropriate foods, and give an extra meal a day for two weeks after recovery. Check a capillary glucose if possible, since poor intake and vomiting predispose to hypoglycaemia; if it is low, give expressed milk or ORS and refer. Re-weigh at 4 hours to confirm weight gain and document the 600 g lost since the earlier weighing.
3. What findings at the 1-hour or 4-hour reassessment would make you abandon oral rehydration and transfer him immediately, and what do you send with him?
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Abandon oral therapy and transfer if: he becomes lethargic or unconscious, is unable to drink or drinks poorly, the skin pinch becomes very slow (2 seconds or more), vomiting persists despite slow small-volume sips so that he keeps nothing down, he develops abdominal distension with absent bowel sounds (ileus or hypokalaemia), he has a seizure, or capillary glucose is low and does not correct with oral sugar. Persistent oliguria with a rising heart rate and worsening capillary refill despite adequate oral intake is also a reason to move. Documented weight loss progressing beyond 9-10% of body weight is another trigger. In practice the threshold should be low here, because the journey takes 90 minutes; do not wait for full-blown shock.
Send with him: a referral note stating the diagnosis, weight, the volume of ORS already given, urine and stool output, temperature and glucose, plus the treatment started (zinc, any antibiotic, antipyretic). Send the mother and the ORS sachets, and continue sips during transport if he is alert and drinking. If a nasogastric tube is available and he is vomiting but not severely dehydrated, ORS 20 mL/kg per hour by tube is an alternative bridge while arranging transfer. Alert the receiving hospital by telephone so a bed and intravenous fluids are ready on arrival, and arrange follow-up weight and zinc completion at the health house after discharge.