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

Resident: Roberts

Date: 1/19/2011

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

Author: Kupietzky, Ari

Journal: Pediatric Dentistry

Volume: 30 Number: 5

Year: 2007

Discussion

The pre-procedural fasting (PF) guidelines by the AAPD for use of Nitrous Oxide state that PF is not required for patients undergoing Nitrous Oxide administration (NOA. Conversely they also state that the practitioner may recommend that only a light meal be consumed in the 2 hours prior to the NOA. No controlled study is referenced supporting the recommendations. PF advocates may argue that the foremost adverse reaction associated with NOA is vomiting; thus if a child has eaten prior to the appointment he or she should not be treated. Dentist who argue that fasting is not a concern with NOA might reason that the incidence of vomiting is extremely low and since the patient remains conscious they continue to maintain their protective reflexes intact - unlike deeply sedated patients. They may also reason that unfed children tend to be cranky and combative thus requiring higher levels of nitrous oxide for optimal sedation which then has a greater chance of inducing nausea and vomiting. Another paradox might be that patients who receive NOA on an empty stomach might be more susceptible to nausea and vomiting. One study suggested that nausea and vomiting are a result of hypoxia and over-sedation.

Method and materials

One hundred and thirteen children (64 male, 49 female), ranging in age from 24 to 160 months and a mean weight of 23 kg, participated in this study. Patients were assigned to two operative appointments. One fasting( 6 hours prior for solids 2 hours for clear liquids), and the other not fasting. During the study patients were titrated up-to no higher than 50% nitrous oxide. No appointment lasted longer than 35 minutes.

Results

Vomiting occurred in one subject immediately after cessation of treatment. The 8 yr. old ( did not specify gender) had consumed a heavy lunch following by a late afternoon snack of chocolate pudding 1 hour prior to treatment. Less than 0.5% of the total treatments (1% of the patients), fasting or non fasting, ended in an event of emesis.

Conclusion

Dentist using Nitrous Oxide for minimal sedation purposes should be aware that an episode of emesis is possible. In the event that a patient has nausea, Nitrous oxide should be turned off and oxygen should be restored to 100% delivery until the patient begins to feel normal. If vomiting does occur, the patients head should be turned to the side allowing the vomitus to pool in the cheek until it can be expectorated or suctioned away. According the author, many other studies cited no significant association between non fasting patients and an increased incidence in emesis during an appointment. We as pediatric dentist should consider carefully the risks and benefits involved with completing the procedure at hand and make our decisions accordingly.