Bhatt M, Cheng W, Roback MG, et al. - In view of their recent multicenter emergency department (ED) procedural sedation cohort study describing a strong correlation between preprocedural opioids and sedation-related adverse events, researchers here investigated whether the timing of opioids influence the incidence of adverse sedation outcomes. From six Canadian pediatric EDs, a prospective cohort of children aged 0 to 18 years who received sedation for a painful procedure from July 2010 to February 2015 was assessed in this secondary analysis. The original cohort comprised 6,295 children; of these, 1,806 (29%) received a preprocedural opioid. In multivariable regression with the timing of opioids modeled as a restricted cubic spline, the highest risk for each outcome was evident when the administration of opioids was done in the 30 minutes prior to sedation. They observed a statistically significant association of the timing of opioid administration with oxygen desaturation and vomiting but not with positive pressure ventilation. These informations may aid clinicians to prepare for sedation and the potential need for patient rescue.