PROBLEM TO BE SOLVED: To provide an infusion needle capable of detecting it reliably with a simple construction that a needle tip comes out of a blood vessel, and a needle removal detecting system.SOLUTION: An infusion needle 1 is constituted to include a tubular needle tube portion 3 opened at its leading end portion. The needle tube portion 3 is formed therein with a needle core side space 9 to function as a needle tube passage for a liquid to pass therethrough, and a circumferential face side space 8 defined liquid-tight from the needle core side space 9 and capable of containing a pressure transmission medium 11 capable of transmitting the pressure of the leading end portion of the needle tube portion 3 to the base end side of the needle tube portion 3.COPYRIGHT: (C)2014,JPO&INPIT【課題】簡単な構成で針先が血管外へ外れたことを確実に検知できる輸液針、および針抜け検知システムを提供する。【解決手段】輸液針1は、先端部分が開口した管状の針管部3を備えて構成されており、該針管部3内には、液が通過可能な針管流路として機能する針芯側空間9と、該針芯側空間9とは液密に区画され、前記針管部3の先端部分の圧力を針管部3の基端側へ伝達可能な圧力伝達媒体11を内在可能な周面側空間8と、が形成されている。【選択図】図2
