Patent ID: 9265915
Filing Date: 2016-02-23
CPC Classification: A61M

Claim Text:
1. A method of indwelling a needle assembly comprising: providing an assembled indwelling needle assembly including: an inner needle having a sharp needlepoint at a distal end; an inner needle hub fixed to a proximal portion of the inner needle; a hollow outer needle in which the inner needle is inserted; an outer needle hub fixed to a proximal portion of the outer needle; and a pressing member, which presses an intermediate portion of the outer needle between a proximal end and a distal end; arranging the indwelling needle assembly into a first position wherein the pressing member is disposed along an axis of the outer needle; moving a distal portion of the indwelling needle assembly to puncture a blood vessel of the patient with the sharp needlepoint of the inner needle with the pressing member contacting the intermediate portion of the outer needle; advancing the outer needle in a distal direction along the inner needle such that the intermediate portion of the outer needle is inserted into the blood vessel and a distal portion of the outer needle is inserted to a target position in the blood vessel; and holding the outer needle or the outer needle hub such that the outer needle is maintained indwelling in the blood vessel while simultaneously pulling the inner needle hub in a proximal direction such that the inner needle is pulled out from and entirely removed from the outer needle; wherein the advancing step includes first pushing the pressing member so as to advance the outer needle a minute distance and then, while holding the inner needle hub in a fixed position, gripping the outer needle hub and pushing the outer needle hub in a distal direction, thereby further advancing the outer needle along the inner needle.