[The history of anesthesia apparatus: basic principles]

The beginnings of modern anesthetic equipment date back to Morton's inhalation flagon in 1846. The numerous devices developed and introduced subsequently can be divided into four groups: 1. Simple ether and chloroform masks for open inhalation anesthesia, from Simpson (1847) to Brown (1928). 2. Vapour inhalators according to the "draw over" principle of Snow (1847) up to the Oxford vaporizer (1941). 3. Closed or half-closed inhalation equipment for ether or chloroform with to and fro breathing, from Clover (1877) to Ombredanne (1908). 4. Equipment for anaesthesia with nitrous oxide. From 1868 onwards this led to the incorporation of gas bottles in anaesthetic equipment and between 1885 and 1890 to the construction of mixing-valves for nitrous oxide and oxygen. In addition, reducing valves, flow meters and vaporizers were developed. The first anaesthetic apparatus with circle system and CO2-absorber was constructed in 1925 by the Dräger factory in Lübeck. Sudeck and Schmidt introduced this technique of anaesthesia in the university hospital of Hamburg-Eppendorf between 1920 and 1925.