Solid blunt for a needle assembly

• US 6,676,636 B2
• Filed: 03/13/2002
• Issued: 01/13/2004
• Est. Priority Date: 12/23/1998
• Status: Expired due to Term

• Current Assignee: Medex Incorporated (Smiths Group International Holdings Ltd.)
• Original Assignee: Medex Incorporated (Smiths Group International Holdings Ltd.)
• Inventors: Chang, Joseph Jawshin, Schmidt, Philip D., Bialecki, Dennis M.
• Primary Examiner(s): Mendez, Manuel
• Assistant Examiner(s): MAYNARD, JENNIFER J
• Application Number:
  US10/098,646
• Publication Number:
  US 20020147428A1
• Time in Patent Office: 671 Days
• Field of Search: 604/160, 604/164, 604/165, 604/166, 604/170, 604/168, 604/263, 604/264, 604/272-274, 604/165.04, 604/164.01, 604/170.01, 604/164.02, 604/166.01, 604/170.02, 604/168.01, 604/165.01, 604/165.02, 604/165.03
• US Class Current: 604/164.02
• CPC Class Codes: A61M 25/0643 Devices having a blunt needle tip, e.g. due to an additional inner component
• CPC Class Codes: A61M 5/32 Needles; Details of needles pertaining to their connection with syringe or hub infusion needles A61M5/158; Accessories for bringing the needle into, or holding the needle on, the body A61M5/42, A61M5/46 take precedence; guide needles for catheters A61M25/065; Devices for protection of needles apparatus specially adapted for cleaning or sterilising needles A61M5/001
• CPC Class Codes: A61M 5/321 Means for protection against accidental injuries by used needles

Abstract

A solid blunt and a needle assembly having a solid blunt. The solid blunt helps to prevent accidental needle sticks. In one exemplary embodiment, a solid blunt has an outer dimension (e.g. outer diameter) which is nearly equal to an inner dimension (e.g. inner diameter) of a cannula of a needle which is configured to contain the solid blunt. In one example, the solid blunt substantially blocks fluid flow in a first circumferential portion of an inner diameter of the cannula and allows fluid flow in a second circumferential portion of the inner diameter. The solid blunt is typically capable of longitudinal movement through the cannula and is prevented from moving substantially in a direction perpendicular to the longitudinal movement. A needle assembly, in another exemplary embodiment, includes a solid blunt, a cannula and a clip which couples slidably the solid blunt to a frame which is coupled to the cannula. The present invention may be used with medical devices including needles, introducers and catheters and other devices as well.

Claims

1. A needle assembly comprising:

a cannula having an inner wall which defines an inner dimension and a sharp tip;

a solid blunt disposed within said cannula, the solid blunt having an outer dimension which is nearly equal to the inner dimension of the cannula, wherein solid blunt has at least a first position and a second position, the first position has the solid blunt disposed entirely within a cannula of a needle, and the second position has the solid blunt advanced sufficiently to extend a tip of the blunt beyond an opening in the cannula and the solid blunt substantially blocks fluid flow in a first space defined by a circumferential portion of the inner wall and allows fluid flow in a second space defined by the circumferential portion of the inner wall in either position.

2. A needle assembly as in claim 1, wherein the cannula has a substantially circular cross-section and the inner dimension is an inner diameter, and wherein the outer dimension is an outer diameter, wherein the solid blunt has a portion of a substantially circular cross-section, and wherein a first portion of the solid blunt having the outer dimension is configured be positioned near the sharp tip.

3. A needle assembly as in claim 2, wherein the solid blunt has one of:

(a) a substantially D-shaped cross-section;

(b) a substantial pie-slice shaped cross-section; and

(c) a circular cross-section having a cut-out region wherein a second portion of the solid blunt extends from substantially near the first circumferential portion to at least a centerline of the cannula.

4. A needle assembly as in claim 3, wherein the cut-out region represents one of a “

U”

shape and a “

V”

shape.

5. A needle assembly as in claim 2, wherein the solid blunt is capable of longitudinal movement through the cannula and is prevented from moving substantially in a direction perpendicular to said longitudinal movement.

6. A needle assembly as in claim 5, wherein the longitudinal movement comprises movement between (a) a first position in which the solid blunt does not extend beyond the sharp tip and is within the cannula, and (b) a second position in which the solid blunt extends beyond the sharp tip and outside of the cannula.

7. A needle assembly as in claim 6, wherein the solid blunt is prevented from rotating in the cannula.

8. A needle assembly as in claim 6, wherein a portion of the solid blunt extends from substantially near the first circumferential portion to at least a centerline of the cannula.

9. A needle assembly as in claim 8, wherein the solid blunt least one-half of the inner diameter.