Accessory anaesthetic breathing systems: checking before use

Accessory or ancillary anaesthesia breathing systems can be defined as all those connected to the fresh gas outlet of the anaesthetic apparatus and us ed instead of the circle system associated with the ventilator, which is th e main circuit. They include: the Mapleson systems, the systems with a nonr ebreathing valve and the disposable systems with a carbon dioxide absorber. They can be a cause of major accidents when not checked before and monitor ed during use. This technical note describes techniques of preanaesthetic c hecking and monitoring during anaesthesia. (C) 1999 Elsevier, Paris.