The introduction of cricoid pressure.
Kopka
A
A
D003413:Cricoid Cartilage; D005764:Gastroesophageal Reflux / Q000517:prevention & control; D049671:History, 18th Century; D049673:History, 20th Century; D006801:Humans; D007442:Intubation, Intratracheal / Q000266:history*; D011312:Pressure