A device for respiratory assistance of a patient includes a tubular element forming a main channel for connection by its distal end to a respiratory tract of the patient, the main channel connecting the patient's respiratory system by its proximal end to the outside, the device further including at least one auxiliary channel for injecting a jet or jets of respirable gas through one or more distal outlet holes of the auxiliary channel or channels, the one or more outlet holes opening-out in the main channel in the vicinity of the distal end of the latter, deflecting elements for deflecting the jets of respirable gas toward the interior of the main channel. The diameter of the outlet hole of each auxiliary channel is less than 150 microns. The outlet holes of the device are shaped as an annular or semi annular strip resulting from assembling/uniting together certain distal outlet holes.
