Bhatt M, Cheng W, Roback MG, et al. - In view of their recent multi-center emergency department (ED) procedural sedation cohort demonstrating a strong correlation between preprocedural opioids and sedation-related adverse events, researchers examined how the timing of opioids influence the incidence of adverse sedation outcomes. A prospective cohort of children aged 0-18 years who underwent sedation for a painful procedure in six Canadian pediatric EDs from July 2010-Feb 2015 was assessed in this secondary analysis. The original cohort comprised 6,295 children; of these, 1,806 (29%) received a preprocedural opioid. Observations revealed a higher incidence of oxygen desaturation, vomiting and positive pressure ventilation (PPV) among patients receiving preprocedural opioids. As per multivariable regression with timing of opioids modeled as a restricted cubic spline, the highest risk for each outcome was evident when opioids were administered in the 30 minutes prior to sedation. Statistically significantly association of timing of opioid administration with oxygen desaturation and vomiting but not with PPV was noted.