The Clinical Presentations of Nitrous Oxide Users in an Emergency Department.

Today, the concomitant abuse of nitrous oxide (N 2 O) and illicit drugs is evident and problematic. However, there are few reports regarding the clinical manifestations of N 2 O users when they present to the emergency department (ED). The purpose of this study was to describe the clinical presentations, the associated illicit substances used in combination, and the outcomes in N 2 O users visiting the ED. This was a retrospective observational cohort study. All N 2 O adult users admitted to the ED at Linkou Chang Gung Memorial Hospital between 2012 and 2020 were included. Demographic variables, clinical symptoms, and examination results were collected from medical records. Univariate comparisons were conducted between pure N 2 O users and combined illicit drug users. A total of 40 patients were included, 24 of which were pure N 2 O users. Limb weakness and numbness accounted for the majority of chief complaints. Neurologic symptoms were the most common clinical manifestations (90%). A more severe ED triage level, faster heart rate, greater agitation, and cardiovascular symptoms were significantly noted in combined illicit drug users. In ED, limb numbness/weakness should arouse physicians' awareness of patients using N 2 O. Combined use of N 2 O and illicit drugs can cause great harm to health.