DEHYDRATION

MERCEDES M. BLACKSTONE, MD, PHILIP SPANDORFER, MD, MSCE, AND MARK D. JOFFE, MD

BACKGROUND (EPIDEMIOLOGY, EVIDENCE)

Acute gastroenteritis continues to be a leading cause of morbidity in both the developed and developing worlds, disproportionately affecting young children. Among children 1 to 5 years of age, diarrhea and dehydration is responsible for up to 10% of all hospitalizations and 3.7-million physician visits per year. Though the majority of these infections are viral, bacterial gastroenteritis and food-borne illnesses add to this enormous toll. Even for those not ill enough to require hospitalization, this affliction continues to be a tremendous burden on the healthcare system in terms of ED and clinic visits and on families in terms of days missed from work and school.

Research has shown that oral rehydration therapy (ORT) is a safe and effective way to rehydrate most children with dehydration secondary to gastroenteritis and it is advocated by the AAP and the CDC. In children with vomiting, a single oral dose of ondansetron given in the ED has been shown to decrease episodes of vomiting and increase the success of ORT, thereby reducing hospital admissions.

Patients who require intravenous hydration, either because they have severe dehydration or because they fail ORT, may benefit from obtaining some dextrose in their fluids in addition to normal saline. Dextrose-containing fluids help to reverse ketosis, which likely contributes to nausea and poor appetite. Studies suggest that patients who receive more dextrose in the ED reduce their ketone levels and may be less likely to require return visits with admission. As such, this pathway advocates a second bolus of 20 cc/kg of D₅NS given over an hour after the initial traditional NS bolus is given in the subset of patients with significant dehydration and ketosis (defined as having ketones on urinalysis or an anion gap >15).