In the context of mild to moderate dehydration in young children, enteral rehydration is the treatment of choice because it is more physiological than parenteral rehydration which has more serious side effects. Thus, nasogastric tube placement has become a more common procedure in the pediatric emergency care setting. Although, it is widely accepted that this procedure is invasive and painful, to date, no analgesic approach has been shown to be effective for children aged 3 months to 3 years. Currently, standard care is the placement of nasogastric tube without any analgesic intervention.~Inhalation of nitrous oxide mixed with oxygen (50/50) has been shown to be effective to reduce pain and anxiety induced by invasive procedures in children, adolescents and adults. Its use is very safe and it is associated with only minor and transient side effects such as nausea, vomiting or dizziness in les than 10% of patients. Its use is very common in many countries such as France, United Kingdom, The Netherlands or Australia. The investigators hypothesized that its inhalation would reduce pain during nasogastric tube placement in young children.~The purpose of this study is to evaluate the analgesic efficacy of 50%/50% nitrous/oxide mixture in reducing pain induced by nasogastric tube insertion in children aged 3 months to 3 years in the pediatric emergency department.~A randomized controlled trial will be performed in two pediatric emergency departments to assess the efficacy of 50/50 nitrous oxide/oxygen during nasogastric tube insertion. The control group will receive standard care.~Primary outcome: Pain assessed with the FLACC scale during tube insertion~The investigators believe that this randomized study comparing nitrous oxide inhalation against current practice (no analgesic means) will highlight the intensity of pain caused by nasogastric tube placement and will assess the effectiveness of nitrous oxide inhalation to reduce pain and anxiety induced by the procedure
Since nitrous oxide/oxygen mixture is effective to reduce pain and anxiety induced by various painful procedures in children, the investigators hypothesized that its inhalation would reduce pain during nasogastric tube placement in young children.~The purpose of this study is to evaluate the analgesic efficacy of 50%/50% nitrous/oxide mixture in reducing pain induced by nasogastric tube insertion in children aged 3 months to 3 years in the pediatric emergency department.