Vascular needle system for visualization of blood has a vascular needle and a tube having a beveled distal end and a proximal end and between the ends a tubular wall having an external surface and an axial cavity for the passage of a fluid between said ends, the needle being provided with at least one lateral aperture and a proximal base-body, the vascular needle system also having a plastic transparent tubular cannula having an internal surface and overlying at least partially the needle.