| 主权项 |
1. An IV catheter assembly comprising: a catheter hub comprising a hollow body having a proximal end and a distal end, the hollow body defining an interior space; a catheter having a proximal end and a distal end, the proximal end of the catheter coupled to the proximal end of the catheter hub; a needle having a needle shaft and a distal tip, the needle moveable between a ready position and a retracted position, in the ready position the distal tip of the needle extending distally from the distal end of the catheter, in the retracted position the distal tip of the needle residing in a position proximal to the proximal end of the catheter, the needle shaft having a change in profile; and a needle guard comprising an elongate arm that extends distally from a base, the base having an aperture formed therein, the needle guard slideably mounted on the needle shaft with the needle shaft passing through the aperture formed in the base, the elongate arm comprising a proximal section and a distal section, the proximal section having a first width and the distal section having a second width, the elongate arm further comprising a mid-section having a portion of a reduced width, the reduced width being less than one or both of the first and second widths so that an indentation is provided in a side of the elongate arm, the elongate arm extending from the base and intersecting the needle shaft along the reduced width portion of the mid-section of the elongate arm located between the proximal and distal sections so that the distal section of the elongate arm is urged against a side of the needle shaft when the needle is in the ready position, the needle guard further comprising an elongate member having a through passage extending between a proximal end and an open distal end of the elongate member, the needle shaft extending through the open distal end of the elongate member when the needle is in the ready position, the elongate member extending distally from a position at or near the base and slideable alongside the needle shaft as the needle is moved between the ready position and the retracted position, when the needle is in the ready position and the retracted position the elongate member extends through the indentation in the mid-section of the elongate arm with the elongate arm intersecting the elongate member at a location between the proximal and distal ends of the elongate member, the through passage of the elongate member having an area of reduced cross-section at a location along the length of the elongate member, the area of reduced cross-section sized so that a portion of an inner wall of the elongate member engages with the change in profile of the needle shaft to limit a proximal movement of the needle with respect to the needle guard. |
