Capnography Predicts Hypoxic Events in Pediatric Procedural Sedation

Hypoventilation is accompanied by a rise in end-tidal carbon dioxide (ETCO₂) levels when the primary mechanism is decreased respiratory rate or by a fall in ETCO₂ when decreased tidal volume causes higher contamination of exhaled air by dead space gases (hypopneic hypoventilation). In a prospective observational study, investigators assessed the association of capnography-measured hypopneic hypoventilation (ETCO₂ <30 mm Hg) with hypoxemia (pulse oximetry <95%) in children and adolescents (age range, 1–21 years; mean age, 5 years) who were undergoing procedural sedation with ketamine with or without midazolam at a pediatric emergency department. Treating providers were blinded to capnography results; supplemental oxygen was not routinely adm…