Children above the age of 5 in the UK can usually cope with viral gastroenteritis without needing medical input. They vomit a few times, move on to the diarrhoeal stage, get thirsty and a bit dehydrated and start drinking just as it all stops, thereby successfully rehydrating themselves and getting on with their lives. So if a vomiting 9 year old is brought to us by a parent who says they’ve been admitted 4 times before for iv fluids , it is probably worth taking a closer look. The shocked, prostrate child we saw in the ED this weekend (a re-presentation) may have cyclical vomiting. More information about this here. Early treatment with anti-emetics and benzodiazepines may help avoid the need for iv fluids.
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Schematic representation of the four phases of Cyclic Vomiting Syndrome and their therapeutic goals. Fleisher et al. BMC Medicine 2005 3:20 doi:10.1186/1741-7015-3-20 Li BUK et al. North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition Consensus Statement on the Diagnosis and Management of Cyclic Vomiting Syndrome. Journal of Pediatric Gastroenterology and Nutrition 2008; 47 : 379–393 (full text, doses etc.)
Patient information: https://www.nhs.uk/conditions/cyclical-vomiting-syndrome/