A mask for delivery of oxygen to a patient, the mask comprising a body having a peripheral portion, when in use to sit comfortably on a patients face, a central portion, and bridge portions extending between the central portion and the peripheral portion and integral therewith, the central portion having an inner surface and an outer surface, the inner surface to be oriented towards the patients face when the mask is in position and contoured so as to sit at a location spaced over the patients nose and mouth, the inner surface of the central portion provided with a wall circumscribing a base, the wall and base being of generally concave configuration and circumscribing a centrally positioned oxygen delivery aperture extending through the central portion between the inner surface and the outer surface, the wall and base configured so as to act as an oxygen diffuser to direct the flow of oxygen generally towards the patients nose and mouth when the mask is in use a fastener to engage the mask to the patient so as to maintain contact between the patients face and said peripheral portion when the mask is in use the patients head to hold the mask in position when in use and means associated with the aperture and of the central portion releasably to receive and secure in position an oxygen delivery tube. In one embodiment, exhaled carbon dioxide may also be collected for measurement. The mask according to the present invention provides comfort, reliability and efficiency in oxygen delivery to patients.Linvention concerne un masque à oxygène pour patient. Ce masque comprend une structure pourvue dune partie périphérique, qui sapplique confortablement sur le visage du patient lors de lutilisation, une partie centrale, ainsi que des parties intermédiaires qui sétendent entre la partie centrale et la partie périphérique desquelles elles sont solidaires. La partie centrale comporte une surface intérieure et une surface extérieure, la surface intérieure devant être orientée ver
