Device for shielding a sharp tip of a cannula and method of using the same

• US 20070073240A1
• Filed: 07/11/2005
• Published: 03/29/2007
• Est. Priority Date: 07/11/2005
• Status: Active Grant

• Current Assignee: Cardinal Health Ireland Unlimited Company (Cardinal Health, Inc.)
• Original Assignee: Sherwood Services AG
• Inventors: Swisher, David, Moos, Kimberly
• Granted Patent: US 7,731,692 B2
• Time in Patent Office: Days
• US Class Current: 604/167.30
• CPC Class Codes: A61B 10/025 for taking bone, bone marrow or cartilage samples
• CPC Class Codes: A61B 2090/08021 of the patient or his organs
• CPC Class Codes: A61M 2202/10 Bone-marrow
• CPC Class Codes: A61M 25/0631 having means for fully covering the needle after its withdrawal, e.g. needle being withdrawn inside the handle or a cover being advanced over the needle
• CPC Class Codes: A61M 5/3213 Caps placed axially onto the needle, e.g. equipped with finger protection guards axially-extensible protective sleeves A61M5/3243
• CPC Class Codes: A61M 5/3273 freely sliding on needle shaft without connection to syringe or needle

Abstract

A safety device for shielding a sharp tip of a tubular needle includes a shaft sized and shaped for being received into the passage of the tubular needle through a first end of the passage and extending to a second end of the passage. A shield is associated with the shaft and is constructed for receiving and substantially shielding the sharp tip of the needle. A catch is associated with the shaft. The catch prevents the withdrawal of the shaft from the passage of the needle when the shield is shielding the sharp tip of the needle.

Claims

1. A safety device for shielding a sharp tip (28) of a cannula (20) having an interior passage including first and second opposite ends, the safety device comprising:

a shaft (55, 155) sized and shaped for being received into the passage of the cannula through the first end of the passage and extending to the second end of the passage;

a shield (48, 148) associated with the shaft and constructed for receiving and substantially shielding the sharp tip of the cannula upon reception of the shaft in the cannula passage;

a catch (60, 160) associated with the shaft, the catch being adapted to prevent withdrawal of the shaft from the passage of the cannula when the shaft is received in the passage in a position where the shield receives the sharp tip of the cannula.

2. A safety device as set forth in claim 1 wherein the catch (60, 160) is mounted on the shaft (55, 155) for movement between a retracted position in which the catch is nearer to the shaft for movement through the passage of the cannula and an extended position in which the catch projects out from the shaft.

3. A safety device as set forth in claim 2 wherein the catch (60, 160) is biased toward the extended position, said catch being adapted to move to the retracted position as it enters the first end of the passage of the cannula (20)and move to the extended position as it exits the second end of the passage.

4. A safety device as set forth in claim 3 wherein the catch (60) comprises a flap (62) partially cut longitudinally from the shaft (55), an associated recess (65), and a living hinge (67) pivotably connecting the flap to the shaft and biasing the flap toward the extended position.

5. A safety device as set forth in claim 4 wherein the flap (62) is substantially received in the recess (65) when it is in the retracted position.

6. A safety device as set forth in claim 3 wherein the catch (160) comprises an engagement member (162) received in a cavity (165) within the shaft (155) and a spring (175) biasing the engagement member to project out of the cavity and into said extended position, wherein the engagement member is substantially received in the cavity when it is in the retracted position.

7. A safety device as set forth in claim 6 wherein a first face (180A) of the engagement member (162) for contacting the tip (28) of the cannula (20) angles away from the tip as the first face contacts the tip such that the engagement member is forced into the cavity (165) and into the retracted position.

8. A safety device as set forth in claim 1 further comprising an absorbent body (57) disposed within the shield (48) for retaining fluid from the passage of the cannula (20) within the shield.

9. A safety device as set forth in claim 8 wherein the absorbent body is made of an anti-microbial material.

10. A safety device as set forth in claim 1 wherein the safety device is an obturator (26, 126) for use in removing a sample from the passage of the cannula (20).

11. A needle assembly (10) for use in collecting samples of tissue and/or bodily fluids, the needle assembly comprising:

a cannula (20) at least partially defining an interior passage including first and second opposite ends, the first end having a sharp tip (28), the passage being adapted to receive the tissue and/or bodily fluid sample;

a shaft (55, 155) sized and shaped for being received into the passage of the cannula through the first end of the passage and extending to the second end of the passage for use in removing a sample collected in the cannula;

a shield (48) associated with the shaft and constructed for receiving and substantially shielding the sharp tip of the cannula upon reception of the shaft in the cannula passage;

a catch (60, 160) associated with the shaft, the catch being adapted to engage the needle assembly to prevent withdrawal of the shaft from the passage of the cannula when the shaft is received in the passage in a position where the shield receives the sharp tip of the cannula.

12. A needle assembly (10) as set forth in claim 11 wherein the catch (60, 160) is mounted on the shaft (55, 155) for movement between a retracted position in which the catch is nearer to the shaft for movement through the passage of the cannula and an extended position in which the catch projects out from the shaft.

13. A needle assembly (10) as set forth in claim 12 wherein the catch (60, 160) is biased toward the extended position, said catch being adapted to move to the retracted position as it enters the first end of the passage of the cannula (20) and move to the extended position as it exits the second end of the passage.

14. A needle assembly (10) as set forth in claim 13 wherein the catch (60) comprises a flap (62) partially cut longitudinally from the shaft (55), an associated recess (65), and a living hinge (67) pivotably connecting the flap to the shaft and biasing the flap toward the extended position.

15. A needle assembly (10) as set forth in claim 14 wherein the flap (62) is substantially received in the recess (65) when it is in the retracted position.

16. A needle assembly (10) as set forth in claim 13 wherein the catch (160) comprises an engagement member (162) received in a cavity (165) within the shaft (155) and a spring (175) biasing the engagement member to project out of the cavity and into said extended position, wherein the engagement member is substantially received in the cavity when it is in the retracted position.

17. A needle assembly (10) as set forth in claim 16 wherein a first face (180A) of the engagement member (162) for contacting the tip (28) of the cannula (20) angles away from the tip as the face contacts the tip such that the engagement member is forced into the cavity and into the retracted position.

18. A needle assembly (10) as set forth in claim 11 further comprising an absorbent body (57) disposed within the shield (48) for retaining fluid from the passage of the cannula (20) within the shield.

19. A needle assembly (10) as set forth in claim 18 wherein the absorbent body (57) is made of an anti-microbial material.

20. A method of shielding a sharp tip (28) of a cannula (20) at least partially defining an interior passage including first and second opposite ends, the method comprising:

collecting a sample of tissue and/or bodily fluid from a patient in the passage of the cannula;

inserting a shaft (55, 155) into the passage through the first end thereof to push the sample out of the second end of the passage to collecting the sample, the step of inserting including shielding the sharp tip of the cannula with a shield (48) when the shaft is inserted a predetermined distance into the cannula;

retaining the shaft relative to the cannula against movement out of the passage through the first end so as to hold the shield over the sharp tip.

21. A method as set forth in claim 20 wherein the step of inserting the shaft (55, 155) into the passage further includes retracting a catch (60, 160) mounted on the shaft as the catch contacts the first end of the cannula so that the catch is nearer to the shaft for movement of the shaft through the passage of the cannula (20).

22. A method as set forth in claim 21 wherein the step of retaining the shaft (55, 155) includes extending the retracted catch (60, 160) to a position in which the catch projects out from the shaft as it exits the second end of the passage.

23. A method as set forth in claim 20 wherein the step of retaining the shaft (55, 155) comprises extending a catch (60, 160) for engagement to retain the shaft in the passage.

24. A method as set forth in claim 23 further comprising releasing the catch (60, 160) to permit the shaft (55, 155) to be withdrawn from the passage.