A<unk>  system or<unk>  is a medical device used to deliver oxygen, remove carbon dioxide, and deliver inhalational anaesthetic agents to a patient. Originally developed for use in anaesthesiology, many variants of<unk>  system are in clinical use, but most comprise a source of fresh gas flow, a length of<unk>  tubing to direct the gas, an adjustable pressure limiting valve to control pressure within the system and direct waste away, and a reservoir bag to allow assisted ventilation.
Breathing circuit
Gas exchange
Airway resistance
Cardiac cycle
Ventilatory threshold
Respiratory adaptation
Cardiovascular physiology
Respirator