ACCESS DEVICE

• US 20080262431A1
• Filed: 04/18/2008
• Published: 10/23/2008
• Est. Priority Date: 04/18/2007
• Status: Active Grant

• Current Assignee: Smiths Medical ASD, Inc. (Smiths Group International Holdings Ltd.)
• Original Assignee: Access Scientific, LLC (Smiths Group International Holdings Ltd.)
• Inventors: Pluth, Richard A., Bierman, Steven F., Huang, Wei, Anderson, Janelle
• Granted Patent: US 8,105,286 B2
• Time in Patent Office: Days
• US Class Current: 604/164.1
• CPC Class Codes: A61B 17/3415 for introducing tubes or catheters, e.g. gastrostomy tubes, drain catheters A61B17/3417 takes precedence; body piercing catheter guide needles A61M25/06
• CPC Class Codes: A61B 2017/347 Locking means, e.g. for locking instrument in cannula
• CPC Class Codes: A61M 2005/1585 Needle inserters
• CPC Class Codes: A61M 2025/09125 Device for locking a guide wire in a fixed position with respect to the catheter or the human body
• CPC Class Codes: A61M 25/0606 "Over-the-needle" catheter assemblies, e.g. I.V. catheters
• CPC Class Codes: A61M 25/0612 Devices for protecting the needle; Devices to help insertion of the needle, e.g. wings or holders

Abstract

An access device places a medical article within a body space of a patient. The device has a needle that includes an elongated body and a needle hub. The device further includes a dilator disposed on and slideable along the elongated body of the needle and a medical article. The medical article is disposed on and slideable along the dilator. A track extends in a proximal direction from the dilator. The needle hub slides along at least a portion of the track between a first position and a second position. The device further includes a locking mechanism operably disposed between the track and the needle hub so as to inhibit further axial movement of the needle in the proximal direction when the needle hub is in the second position.

Claims

1. An access device for placing a medical article within a body space, comprising:

a needle having an elongated needle body with a distal end and a hub from which the needle body extends;

a dilator disposed on the needle body, the needle and the dilator being moveable relative to each other from a first position, wherein the distal end of the needle lies distal of the dilator, and a second position wherein the distal end of the needle lies within the dilator, the dilator including a dilator hub and an elongated dilator shaft that extends from the dilator hub; and

a locking mechanism operating between the needle and the dilator to inhibit movement of the needle relative to the dilator when in the second position, the locking mechanism being configured to allow movement of the needle from the first position toward the second position without engagement by the locking mechanism so as to lessen resistance to the movement.

2. The access device of claim 1, wherein a longitudinal length of the needle is greater than a longitudinal length of the dilator, and a distance between the first position and the second position is less than a longitudinal length of the needle.

3. The access device of claim 1 additionally comprising a medical article disposed on the dilator, the medical article and the dilator being movable relative to each other.

4. The access device of claim 1, wherein the medical article is a catheter.

5. The access device of claim 1, wherein the medical article is a sheath.

6. The access device of claim 5, wherein the sheath is configured to receive at least a portion of a catheter.

7. The access device of claim 1, wherein the locking mechanism comprises a first member supported on the proximal side of and spaced from the dilator hub and a second member supported by the needle, the first and second members being configured to engage each other when the needle hub is moved through a distance away from the dilator hub, said distance being greater than a distance by which the distal end of the needle body extends beyond the dilator when the hubs of the needle and dilator are juxtaposed.

8. The access device of claim 7, wherein an elongated support suspends the first member of the locking mechanism at a location spaced from the dilator hub.

9. The access device of claim 8, wherein the elongated support and the needle hub include cooperating structure such that the needle slides along the elongated support.

10. The access device of claim 9, wherein the elongated support is rotatably coupled to the dilator hub.

11. The access device of claim 8, wherein the elongated support lies generally parallel to a longitudinal axis of the needle body.

12. The access device of claim 8, wherein the elongated support extends to the proximal side of the dilator hub.

13. The access device of claim 8 additionally comprising a guidewire extending distally from a guidewire cap, the guidewire cap being releasably coupled to the elongated support.

14. The access device of claim 13, wherein the guidewire cap engages the elongated support at a location proximate of the first member of the locking mechanism.

15. The access device of claim 1, wherein the needle body includes at least one fenestration and the dilator shaft includes at least one fenestration that communicates with the needle fenestration.

16. The access device of claim 15, wherein one of said fenestrations has a greater dimension in at least one direction than the other one of said fenestrations.

17. The access device of claim 15 additionally comprising a medical article coaxially disposed about the dilator shaft, and at least one elongated channel formed between the dilator shaft and the medical article that extends along at least a substantial portion of the length of the dilator shaft, the channel communicating with the fenestration in the dilator shaft and having a dimension, in a direction perpendicular to the length of the dilator shaft, that is less than a maximum outer diameter of the dilator shaft.

18. The access device of claim 15 additionally comprising a medical article coaxially disposed about the dilator shaft, and at least one elongated channel formed between the dilator shaft and the medical article that extends along at least a substantial portion of the length of the dilator shaft, the channel communicating with the fenestration in the dilator shaft and having a span angle of less than 360 degrees about a longitudinal axis of the dilator.

19. An access device for placing a medical article within a body space, comprising:

a needle including a needle body having a longitudinal axis with a distal tip and a needle hub from which the needle body extends;

a dilator including a dilator shaft and a dilator hub, the dilator shaft being disposed on and slideable along the needle body with the dilator hub being disposed distal of the needle hub;

a medical article comprising a tubular section and a hub, the tubular section being disposed on and slideable along the dilator with the hub being disposed distal of the dilator hub;

a track extending from the dilator hub in a proximal direction; and

a locking mechanism operably disposed between the track and the needle so as to selectively inhibit proximal movement of the needle relative to the dilator.

20. The access device of claim 19, wherein the needle comprises at least one tang engaging the track.

21. The access device of claim 19, wherein the track is rotatable around the longitudinal axis of the dilator hub.

22. The access device of claim 19, wherein the locking mechanism comprises at least one finger element projecting from the track.

23. The access device of claim 19, wherein a width of the track varies along its longitudinal length.

24. The access device of claim 19, wherein the needle is configured to slide along at least a portion of the track between a first position and a second position, the second position being on a proximal side of the first position, the locking mechanism inhibiting further proximal movement of the needle when the needle is in the second position.

25. The access device of claim 24, wherein a longitudinal length of the dilator is sufficiently long so that the distal tip of the needle body lies within the dilator at least when the needle is in the second position.

26. The access device of claim 24, wherein the locking mechanism comprises a slot in the track, the slot being arranged perpendicular to the longitudinal axis and being configured to receive the at least one tang of the needle at least when the needle is in the second position.

27. The access device of claim 19 further comprising a guidewire, the needle body and the guidewire being coaxially disposed with the guidewire slideable through at least a portion of the needle body.

28. The access device of claim 27, wherein the guidewire comprises a wire and a hub, the hub being configured to engage with the needle hub.

29. The access device of claim 28 further comprising a second locking mechanism operably disposed between the track and the guidewire hub, the second locking mechanism being configured to selectively release the guidewire hub from the track so as to allow the guidewire hub to move in a distal direction as the guidewire slides through the needle body.

30. The access device of claim 29, wherein the second locking mechanism comprises:

an element protruding from the track and configured to inhibit longitudinal movement of the hub in a proximal direction relative to the track;

at least one arm projecting from the track on a distal side of the element, the at least one arm being configured to selectively inhibit movement of the hub in at least a lateral direction relative to the track; and

a stop protruding from the track on a distal side of the at least one arm, the stop being configured to selectively inhibit longitudinal movement of the hub in the distal direction relative to the track.

31. The access device of claim 19, wherein the track is rotatably coupled to the dilator.

32. The access device of claim 19, wherein a third locking mechanism operates between the needle hub and the dilator hub.

33. The access device of claim 32, wherein the third locking mechanism is unlocked by relative rotational movement between the needle and dilator hubs, and wherein the needle hub includes a longitudinal tab that projects above an outer surface of the dilator hub

34. The access device of claim 33, wherein the needle body includes a beveled distal tip and the tab is located on a side of the needle hub that corresponds with the side of the needle body on which the bevel is formed.

35. An access device for placing a medical article within a body space, comprising:

a needle having a distal end and a first fenestration;

a dilator disposed on and slideable along the needle and having a second fenestration, wherein one of the first and second fenestrations has a greater dimension in at least one direction than the other one of the first and second fenestrations in said direction; and

a medical article being coaxially disposed and longitudinally movable over the dilator.

36. The access device of claim 35, wherein the at least one direction is a longitudinal direction.

37. The access device of claim 35, wherein the at least one direction is circumferential.

38. The access device of claim 35, wherein a shape of the first fenestration is oblong and a shape of the second fenestration is round.

39. The access device of claim 35, wherein a shape of each of the first and second fenestrations is oblong.

40. The access device of claim 35, wherein the first oblong fenestration is arranged generally perpendicular to the second oblong fenestration.

41. An access device for placing a medical article within a body space, comprising:

a needle having a distal end and at least one fenestration;

a dilator including a shaft disposed on at least a portion of the needle;

a medical article disposed on at least a portion of the dilator; and

at least one elongated channel disposed between the needle and an exterior surface of the medical article that extends along at least a substantial portion of the length of the dilator shaft, the channel communicating with the fenestration in the needle and having a span angle of less than 360 degrees about a longitudinal axis of the dilator.

42. The access device of claim 41, wherein the dilator comprises a second fenestration, the second fenestration communicating with the fenestration in the needle.

43. The access device of claim 42, wherein at least a portion of the second fenestration aligns with a portion of the fenestration in the dilator.

44. The access device of claim 41, wherein the channel is disposed between the dilator and the medical article.

45. The access device of claim 44, wherein the channel is defined at least in part by at least one longitudinal groove formed on an outer surface of the dilator shaft.

46. The access device of claim 44, wherein the groove has a span angle of around 120 degrees.

47. The access device of claim 44, wherein at least a portion of the groove has a radial dimension of approximately 0.001 inches.

48. The access device of claim 44, wherein the longitudinal groove follows a spiral path along at least a portion of the length of the dilator shaft.

50. The access device of claim 44, wherein the groove has a longitudinal length less than a length of the dilator shaft.

51. The access device of claim 44, wherein the distal end of the groove lies proximal of a distal end of the dilator.

49. The access device of 44 additionally comprising a second longitudinal groove diametrically opposed to said other groove on an outer surface of the dilator shaft.

52. A method of removing a needle and dilator assembly from a patient where the dilator is coaxially disposed about at least a portion of the needle, comprising:

moving a needle relative to a dilator from a first position to a second position, wherein a distal end of the needle lies distal of the dilator in the first position, and wherein the distal end of the needle lies within the dilator in the second position; and

inhibiting further movement of the needle relative to the dilator once the needle is in the second position.

53. The method of claim 52 additionally comprising conducting a fluid through generally aligned fenestrations when the needle is in the first position, and misaligning the fenestration in the dilator with the fenestration in the needle when the needle is in the second position.

54. The method of claim 52 further comprising locking the needle to the dilator when the needle is in the first position.

55. The method of claim 54, wherein the step of locking the needle comprises rotating the needle relative to the dilator about a common axis.

56. An access device for placing a medical article within a body space, comprising:

a needle having a distal end and a longitudinal axis;

a dilator disposed on at least a portion of the needle and having an outer surface; and

a medical article disposed on at least a portion of the dilator and having an inner surface, at least a portion of the inner surface of the medical article having a dissimilar shape than an adjacent portion of the outer surface of the dilator so as to form a gap therebetween, the gap extending along the longitudinal axis.

57. The access device of claim 56, wherein the outer surface of the dilator is oblong and the inner surface of the medical article is round.

58. The access device of claim 56, wherein the outer surface of the dilator is round and the inner surface of the medical article is square.

59. The access device of claim 56, wherein the gap follows a spiral path along the longitudinal axis.

60. The access device of claim 56, wherein the gap follows a linear path along the longitudinal axis.

61. The access device of claim 60, wherein the linear path is parallel to the longitudinal axis.

62. The access device of claim 56, wherein a thickness of the gap varies along at least a portion of a length of the gap.

63. The access device of claim 56, wherein one of the medical device and the dilator include an a grooved surface.