Guedel Airway 

They are designed to allow free airflow, An orpharyngeal Airway (also known as OPA) or Oral Airway or Guedel Pattern Airway, It is a medical device called an airway adjunct used to maintain an open airway. It does this by preventing the tongue form covering the epiglottis, which could prevent the patient form breathing, When a person becomes unconscious, the muscles in their jaw relax and may allow the tongue to obstruct the windpipe or airway.

Guedel airways come in a variety of sizes, and are used commonly in pre-hospital emergency care and for short term airway management post anaesthetic or when manual methods are inadequate to maintain an open airway.