Device for introducing a catheter with a security non-piercing cage provided with a flexible blade

An arrangement for the insertion into the body, through the skin, of a catheter with a proximal base, where this arrangement includes a needle which has a puncture end and a cage, which extends the base in the proximal direction, where this cage forms a chamber through which the needle slides from a proximal entrance to an opposite distal exit and is equipped with a sprung flexible steel blade to hold the puncture end of the needle in the chamber when the needle is withdrawn from the cannula, wherein this blade comprises a transverse branch positioned across the chamber close to the proximal entrance of the chamber perpendicular to the needle and traversed by the needle, where the blade and the needle include resources that combine so that the transverse branch is at rest and traversed freely by the needle when the needle is pushed in the distal direction, and so that the transverse branch stops the needle and is bent by the needle when the needle is drawn in the proximal direction beyond a given axial position, so that the bent transverse branch inclines the needle and applies a return force to the needle which tends to force the needle back in the distal direction until the puncture end comes up against a wall of the chamber.