422 - Does Overuse of Ondansetron in a Pediatric Emergency Room Cause Diagnostic Delays?

Poster Number: 422
Publication Number: 422.3201

Background: Ondansetron has been shown to decrease the length of emergency department (ED) stays for children with acute gastroenteritis (AGE) by inhibiting vomiting and allowing for oral rehydration. Ondansetron use in the ED has broadened beyond AGE and is commonly used to treat vomiting only. Expanded use for a specific symptom could introduce diagnostic uncertainty.

Objective: Our aim was to assess the use of Ondansetron beyond the scope of AGE in a pediatric ED.

Design/Methods: A retrospective chart review of patients aged 1 month to 17 years receiving Ondansetron at a busy pediatric ED between 2/1/2023 and 4/30/2023 was performed using the electronic medical record for Cerner called PowerChart. Exclusion criteria included patients with Ondansetron on their medication list from home, oncology patients, and patients receiving Ondansetron as an adjunctive medication for sedation. Possible risk factors for delayed diagnoses included route and number of Ondansetron doses, as well as vomiting, diarrhea, nausea, fever, abdominal pain, bloody stools, or signs of dehydration being present within 24 hours of the visit. Review of discharge diagnoses, return to the ED within 48 hours, and returning diagnoses were recorded and compared using risk factors and a logistic regression model.

Results: 1618 subjects were reviewed. 76 (4.7%) returned to the ED within 48 hours. Of those 76, we identified 8 (10.5%) diagnostic delays in which the returning diagnosis differed considerably from the original. There was a ninth subject, originally diagnosed with vomiting, who passed away from nonaccidental abdominal trauma after returning to the ED within 96 hours. Hence, 9 of the 1618 subjects (0.6%) experienced a delayed final diagnosis after receiving Ondansetron at their original visit. There was no statistically significant correlation between the risk factors reviewed and these 9 cases when compared to the 1618 total cases and 76 who returned.

Conclusion(s): Only 0.6% of those provided Ondansetron at a pediatric ED had a delayed diagnosis, suggesting that pediatric ED Ondansetron use is generally safe and rarely causes diagnostic uncertainty. Unfortunately, the results did not distinguish a risk factor to help discern a delayed diagnosis. However, knowing that 10.5% of the 76 who returned within 48 hours of receiving Ondansetron had a delayed diagnosis may help inform pediatric providers to expand their differential diagnoses when patients return after receiving Ondansetron.