Do children with high body mass indices have a higher incidence of emesis when undergoing ketamine sedation?

The objective of this study was to determine if overweight children are more likely than normal-weight children to require ondansetron when undergoing ketamine sedation in a pediatric emergency department. Patients between the ages of 2 and 18 years with an American Society of Anesthesiologists classification of I or II who underwent intravenous procedural sedation with ketamine with or without midazolam for uncomplicated forearm fracture reduction in an urban pediatric emergency department during the year 2007 were included. A review of sedation records was conducted for each visit. Data collected included demographics, sedation time, and doses of medications administered. Body mass index (BMI) was calculated using an estimated height for the 50th percentile for age and sex. In 2007, all patients underwent procedural sedation per protocol. Per protocol, patients did not prophylactically receive ondansetron during procedural sedations. During the study period, 141 patients were identified who met inclusion criteria. Of these, 110 had an estimated BMI less than 25 kg/m; 31 had an estimated BMI of 25 kg/m or greater. Ten patients (7.1%) received ondansetron. Patients in the high-BMI group were more likely to have received ondansetron than those in the normal-BMI group (16.1% vs 4.5%, P = 0.04). Our data suggest that pediatric patients with high BMIs are at greater risk for nausea or emesis during ketamine sedation. Clinicians should consider prophylactic administration of ondansetron to this group of patients before performing ketamine sedation.