公开(公告)号：CA2211752A1

公开(公告)日：1998-02-05

申请号：CA2211752

申请日：1997-07-30

Applicant: BECTON DICKINSON CO

Inventor： GRIFFITH RICHARD LEE ,  NEWELL JONATHAN C ,  MESSINA RALPH F ,  EDIC PETER M ,  HOUGHTON FREDERICK CHARLES ,  STROWE ROBERT J

IPC: A61B5/05 ,  A61M19/00 ,  A61N1/05 ,  A61N1/36

Abstract: An electrolocation apparatus is provided for locating a nerve to which anesthesia may be delivered. The apparatus includes a needle assembly having an electrically conductive needle cannula non-conductive tube secured over the needle cannula, and a conductive plating on the tube. The conductors are connected to astimulator that generates alternating high and low charge pulses with a constant low current level. The high charge pulses generate noticeable muscle twitches immediately after insertion of the needle into the patient. Muscle twitches responsive to the high charge pulses will peak in magnitude, and muscle twitchesresponsive to the low charge pulses will become observable as the needle approaches the targeted nerve, and will be indistinguishable from the muscle twitches responsive to the high charge pulses when the needle is in a position for administration ofanesthetic.