Appropriate sedation is important for a well-tolerated bronchoscopic procedure. Pre-assessment of the child is essential in order to anticipate potential difficulties and complications. The available techniques include conscious and deep sedation. Various protocols may be used during flexible bronchoscopy that entail the administration of a single oral or intravenous drug or drug combination (e.g. midazolam, meperidine, propofol, ketamine, remifentanyl), or inhalational agents (premixed nitrous oxide, sevoflurane). Whichever the choice of sedation and the technique of oxygen delivery (nasal prongs, face mask, laryngeal mask, endotracheal intubation), it is essential to maintain and preserve spontaneous ventilation. Controlled ventilation is often used during rigid bronchoscopy for foreign-body removal. The most frequent complication of sedation is hypoxaemia, either as an isolated problem or in association with laryngospasm and/or bronchospasm. Transcutaneous oxygen desaturation can be secondary to partial or total airway obstruction by the bronchoscope and/or depression due to sedation. Pre-operative detection of high-risk patients, administration of appropriate anaesthesia and monitoring of patients are essential for a successful procedure and help to minimize potential complications.