The efficiency of two patient-dependent, variable performance techniques of oxygen therapy in relieving hypoxaemia after upper abdominal surgery was compared. A high-flow system delivered a humidified mixture of oxygen 2 litre min-1 and air 13 litre min-1 through a cannula inserted into the anterior nares. The low-flow system delivered 2 litre min-1 of dry oxygen into the nasopharynx through a ...
