title: A modified expiratory valve for teaching.
abstract: The shrouding of anaesthetic expiratory valves prevents the anaesthetist from either seeing valve disc movement or hearing clearly the escape of gas during expiration. A modification to one type of valve (Medishield II) is described which replaces this lost information by providing a direct indication of valve opening.
authors.affiliation: Shackleton Department of Anaesthetics, Southampton General Hospital.
authors.forename: A J
authors.initials: AJ
authors.lastname: Sansome
authors.forename: R
authors.initials: R
authors.lastname: Bacon
mesh_terms: D000776:Anesthesiology / Q000193:education / Q000295:instrumentation*; D004503:Education, Medical, Graduate; D004867:Equipment Design; D006801:Humans; D011312:Pressure; D013663:Teaching; D012122:Ventilators, Mechanical