Source:http://linkedlifedata.com/resource/umls/id/C1139760
UMD: Needles designed for withdrawal and reinfusion of blood from the peripheral circulatory system after processing in an external hemodialysis machine. These devices typically consist of thin-walled needles of appropriate diameter (typically 14 to 19 gauge) and length to be introduced in arteries and veins and connected to the blood line of a dialysis machine. Hemodialysis needles are available either with a single lumen for alternating flow procedures or with two coaxial lumens for simultaneous withdrawal/infusion procedures; they may be used for periodical long-term treatments or for one-time emergency procedures.