title: An unseen obstruction.
authors.forename: B
authors.initials: B
authors.lastname: Stanley
authors.forename: P
authors.initials: P
authors.lastname: Roe
mesh_terms: D000402:Airway Obstruction / Q000209:etiology*; D002648:Child; D004868:Equipment Failure; D006801:Humans; D008397:Masks / Q000009:adverse effects*; D010102:Oxygen Inhalation Therapy / Q000295:instrumentation; D011183:Postoperative Complications