title: Nitrous oxide inhalation is a safe and effective way to facilitate procedures in paediatric outpatient departments.
abstract: OBJECTIVE
  To evaluate the efficacy and safety of nitrous oxide treatment given to children presenting procedural problems in a paediatric outpatient department.
  
  
  METHODS
  The study comprised 70 children 6-18 years old. Two different groups were studied. (1) Children presenting with problems in establishing venous cannulation (VC) (n = 50). The patients were randomised to conventional treatment (CO); cutaneous application of EMLA or nitrous oxide treatment (NO); N2O and EMLA. (2) Anxious children/children undergoing painful procedures who repeatedly come to the clinic (n = 20). These children underwent two procedures with CO/NO, the order of priority being randomised. Altogether the study included 90 procedures. Main outcome measures were procedure time, number of attempts required to establish VC, pain, and evaluation.
  
  
  RESULTS
  All procedures were performed with NO while four VC (8%) were not possible to perform with CO. The number of attempts required to establish VC was lower when using NO (median 2, range 2-9), compared with CO (median 4, range 2-9). The estimated pain was lower with NO. The total mean time required was similar for NO and CO when the time required for the NO procedure was included. One complication, tinnitus, was observed; it disappeared within 3 minutes.
  
  
  CONCLUSIONS
  The pretreatment with nitrous oxide is a time effective and safe method for use at paediatric outpatient departments to reduce pain, facilitate venous cannulation, and thereby reduce the number of costly cancellations of planned procedures.
authors.affiliation: Department of Pediatrics, Endocrine Research, Karolinska University Hospital, Huddinge, Stockholm, Sweden.
authors.forename: K
authors.initials: K
authors.lastname: Ekbom
authors.forename: J
authors.initials: J
authors.lastname: Jakobsson
authors.forename: C
authors.initials: C
authors.lastname: Marcus
mesh_terms: D000293:Adolescent; D000700:Analgesics / Q000008:administration & dosage; D018685:Anesthetics, Inhalation; D001007:Anxiety / Q000517:prevention & control*; D002404:Catheterization; D002648:Child; D005260:Female; D006801:Humans; D008012:Lidocaine / Q000008:administration & dosage; D000077442:Lidocaine, Prilocaine Drug Combination; D008297:Male; D009609:Nitrous Oxide; D009824:Ointments; D010045:Outpatients; D010146:Pain / Q000517:prevention & control*; D010372:Pediatrics; D011318:Prilocaine / Q000008:administration & dosage; D018709:Statistics, Nonparametric
chemical_list: D000700:Analgesics; D018685:Anesthetics, Inhalation; D000077442:Lidocaine, Prilocaine Drug Combination; D009824:Ointments; D011318:Prilocaine; D008012:Lidocaine; D009609:Nitrous Oxide