A system for detecting manual ventilation and selectively delivering a high flow of oxygen. The system comprises a source of compressed oxygen coupled to a first lumen of a nasal cannula, with an oxygen flow control valve coupled to a processor to control the flow of oxygen to the nasal cannula. A second lumen of the nasal cannula is in connection with a pressure sensor and the pressure sensor in connection with the processor. The processor may receive the pressure values and be programmed to determine when manual ventilation has occurred, and send a signal to the oxygen flow control valve to send a high flow of oxygen in response to manual ventilation.