Abstract: An I.V. cannula needle (37) has a base adapter (41) with a sleeve (43) which surrounds a compression spring (53) which urges a barrel (47) and its tapered point (49) to cover and protect the point (39) of the I.V. needle (37) An I.V. cannula (52) slips over the barrel (47) and has a winged base (55) which, when pulled backward, compresses a spring (53) inside a base extension (43) and exposes the needle point (39) for insertion. On withdrawing needle (37) and relaxing pull-back pressure, needle point (39) is automatically shielded by the point (49) of the barrel (47), but the loose-fitting I.V. cannula remains in the patient and is taped down and connected to I.V. tubing. A second embodiment comprises a wire (61) which can be manipulated back and forth through a barrel (81) by a winged member (69) operating within a slot (80) and against a spring (67). The wire (61) can protrude through the needle 81 and provide protection against accidental injury from the needle. An I.V.