Fasting State and Episodes of Vomiting in Children Receiving Nitrous Oxide for Dental Treatment

Purpose: The purpose of this controlled-crossover study was to determine the frequency of vomiting during nitrous oxide / oxygen analgesia (NOA) and assess the relationship between fasting status and vomiting.

Methods: One hundred and thirteen children (64 male, 49 female), ranging in age from 24-160 months (mean = 74) and a mean weight of 23 kg (range 11-60 kg), participated in the study. At the initial examination, subjects were randomly assigned to be either fasting on the first appointment and non-fasting during the second appointment or alternatively be non-fasting for the first appointment and fasting for the second.

Results: The average time interval between eating and treatment in the fasting sessions was 6 hours and in the non-fasting group, 1 hour before treatment. Vomiting occurred in only one subject, immediately after cessation of treatment resulting in a frequency of 1% of subjects or 0.5% of sessions. No other differences were found between fasting and non-fasting subjects.

Conclusion: During dental treatment with NOA using the rapid induction method, constant nonfluctuating concentration/ flow, and treatment time of under 35 minutes, the frequency of vomiting during NOA was found to be 0.5%.