Detachable guide needle

Claim 1

A detachable guide needle for use with a flexible catheter in withdrawing or introducing fluids relative to a body, said needle comprising a hollow tubular, one-piece, elongated sheet material element having handle means at one end and a sharpened configuration at the other end for insertion of said needle into said body, detachment means for removing said needle from said catheter after insertion into said body including a line of separation and separate break-apart hinge means each being generally opposed to each other and extending longitudinally throughout the entire length of said needle, said hinge means including a plurality of integral, break-apart connecting webs extending at longitudinally spaced intervals, said handle means including a pair of integral wing sections iniTially juxtaposed relative to one another and located on opposite sides of the line of separation to permit application of the needle to said body and subsequent opening of said needle along said line of separation by said handle means, each of the integral connecting webs except the one adjacent the end of said needle which includes said handle means being frangible at generally the same predetermined fracture level to permit severance of said integral connecting webs when said needle is opened up a predetermined amount along said line of separation, the integral connecting web at said one end being thicker in cross section and thereby having a higher fracture level so as to be capable of maintaining the frangible integral connecting webs as hinges until sufficient force is applied to weaken and fracture first the frangible integral connecting webs having generally the same predetermined fracture level and then the integral connecting web having the higher fracture level, whereby to provide detached sections of said needle facilitating complete removal from the catheter.