BACKGROUND There is ongoing debate regarding the optimal timing for tracheal extubation in children at increased risk of perioperative respiratory adverse events, particularly following adenotonsillectomy. OBJECTIVE To assess the occurrence of perioperative respiratory adverse events in children undergoing elective adenotonsillectomy extubated under deep anaesthesia or when fully awake. METHODS Prospective, randomised controlled trial. METHODS Tertiary paediatric hospital. METHODS One hundred children (<16 years), with at least one risk factor for perioperative respiratory adverse events (current or recent upper respiratory tract infection in the past 2 weeks, eczema, wheezing in the past 12 months, dry nocturnal cough, wheezing on exercise, family history of asthma, eczema or hay fever as well as passive smoking). METHODS Deep or awake extubation. METHODS The occurrence of perioperative respiratory adverse events (laryngospasm, bronchospasm, persistent coughing, airway obstruction, desaturation <95%). RESULTS There were no differences between the two groups with regard to age, medical and surgical parameters. The overall incidence of complications did not differ between the two groups; tracheal extubation in fully awake children was associated with a greater incidence of persistent coughing (60 vs. 35%, P = 0.028), whereas the incidence of airway obstruction relieved by simple airway manoeuvres in children extubated while deeply anaesthetised was greater (26 vs. 8%, P = 0.03). There was no difference in the incidence of oxygen desaturation lasting more than 10 s. CONCLUSIONS There was no difference in the overall incidence of perioperative respiratory adverse events. Both extubation techniques may be used in high-risk children undergoing adenotonsillectomy provided that the child is monitored closely in the postoperative period. BACKGROUND Australian New Zealand Clinical Trials Registry: ACTRN12609000387224.