I.V. catheter with self-locating needle guard

Abstract

An I.V. catheter is described, including a catheter and hub assembly and a needle and hub assembly. A needle guard, including a tubular distal portion and a split proximal flange, is located about the needle at the distal end of the needle hub. The needle includes a slot near the needle tip. As the needle assembly is withdrawn from the catheter, the needle guard slides along the needle until the split flange engages the needle slot, which locks the tubular distal portion of the guard over the needle tip.

What is claimed is: 
     
       1. An I.V. catheter with a self-locating needle guard comprising: a catheter assembly including a catheter attached to a hollow catheter hub;   an introducer needle assembly, including a hollow needle with a distal tip, said needle being affixed near its proximal end to a needle hub, the distal end of said needle hub being suitable for engagement with said hollow catheter hub, and said needle including means for engaging a needle guard; and   a needle guard including a proximal portion having means for engaging said engaging means of said needle and a distal portion for extending over said needle tip when said proximal portion is engaged with said engaging means of said needle, said needle guard located proximal said catheter and distal said needle hub and mounted for relative motion with respect to said needle as said needle is withdrawn from said catheter until said engaging means of said needle guard engages said engaging means of said needle; and   retaining means for retaining said needle guard within said catheter hub prior to engagement of said needle engaging means and said needle guard engaging means.   
     
     
       2. The I.V. catheter of claim 1, wherein said engaging means of said needle comprises an engagement slot located near said distal tip of said needle. 
     
     
       3. The I.V. catheter of claim 2, wherein said distal portion of said needle guard comprises a cylindrical portion having an inner diameter slightly larger than the outer diameter of said needle. 
     
     
       4. The I.V. catheter of claim 3, wherein said proximal portion of said needle guard comprises a flange having a central aperture aligned with said distal cylindrical portion, and said needle guard engaging means includes an axially aligned expansion slot passing through said flange. 
     
     
       5. The I.V. catheter of claim 4, wherein said needle guard becomes locked in engagement with said needle when the rim of said flange aperture engages said engagement slot of said needle. 
     
     
       6. The I.V. catheter of claim 4, wherein the diameter of said flange aperture is less than the outer diameter of said needle, whereby said needle spreads said flange about said expansion slot when the full diameter of said needle passes through said flange aperture.   
     
     
       7. The I.V. catheter of claim 1, wherein said proximal portion of said needle guard comprises a radially extending flange having a central aperture, and said retaining means includes an axially aligned expansion slot passing through said flange, whereby said flange is brought into contact with said catheter hub when said expansion slot opens in response to the passage of said needle through said central aperture.   
     
     
       8. An I.V. catheter with a self-locating needle guard comprising: a catheter assembly including a catheter attached to a catheter hub;   an introducer needle assembly for connection with said catheter assembly, including a hollow needle with a distal tip and a needle hub, said needle being affixed near its proximal end to extend distally exposed from the distal end of said needle hub, and said needle including means located distal said distal end of said needle hub for engaging a needle guard; and   a needle guard, initially located about said needle at the distal end of said needle hub and capable of axial movement relative to said needle, said needle guard including a proximal portion having means for engaging said engaging means of said needle and a distal portion for extending over said needle tip when said proximal portion is engaged with said engaging means of said needle; and   retaining means for retaining said needle guard within said catheter hub prior to engagement of said needle engaging means and said needle guard engaging means.   
     
     
       9. The I.V. catheter of claim 1, wherein said catheter hub further includes means for retaining said needle guard within said catheter hub prior to engagement of said needle engaging means and said needle guard engaging means. 
     
     
       10. The I.V. catheter of claim 9, wherein said retaining means includes a projection extending from said catheter hub and abutting said needle guard prior to engagement of said needle engaging means and said needle guard engaging means. 
     
     
       11. The I.V. catheter of claim 3, wherein said proximal portion of said needle guard includes an expandable central aperture which, in its unexpanded condition, has an inner diameter which is less than the outer diameter of said needle. .Iadd. 
     
     
       12.  The I.V. catheter of claim 8, wherein said proximal portion of said needle guard comprises a radially extending flange having a central aperture, and said retaining means includes an axially aligned expansion slot passing through said flange. .Iaddend. .Iadd.13. The I.V. catheter of claim 8, wherein said catheter hub further includes means for retaining said needle guard within said catheter hub prior to engagement of said needle engaging means and said needle guard engaging means. .Iaddend. .Iadd.14. The I.V. catheter of claim 8, wherein said retaining means includes a projection extending from said catheter hub and abutting said needle guard prior to engagement of said needle engaging means and said needle guard engaging means. .Iaddend. .Iadd.15. The I.V. catheter of claim 8, wherein said engaging means of said needle comprises an engagement slot located near said distal tip of said needle. .Iaddend. .Iadd.16. The I.V. catheter of claim 15, wherein said distal portion of said needle guard comprises a cylindrical portion having an inner diameter slightly larger than the outer diameter of said needle. .Iaddend. .Iadd.17. The I.V. catheter of claim 16, wherein said proximal portion of said needle guard includes an expandable central aperture which, in its unexpanded condition, has an inner diameter which is less than the outer diameter of said needle. .Iaddend. .Iadd.18. The I.V. catheter of claim 16, wherein said proximal portion of said needle guard comprises a flange having a central aperture aligned with said distal cylindrical portion, and said needle guard engaging means includes an axially aligned expansion slot passing through said flange. .Iaddend. .Iadd.19. The I.V. catheter of claim 18, wherein said needle guard becomes locked in engagement with said needle when the rim of said flange aperture engages said engagement slot of said needle. .Iaddend. .Iadd.20. The I.V. catheter of claim 18, wherein the diameter of said flange aperture is less than the outer diameter of said needle. .Iaddend. .Iadd.21. A catheter assembly comprising: a catheter hub;   a catheter attached to said catheter hub;   a needle hub;   a needle comprising:   a distal tip, a proximal end, said needle affixed near its proximal end to said needle hub, and first means for engaging a needle guard;   a needle guard comprising:   a proximal portion having second means for engaging said first means, and a distal portion for extending over said needle distal tip when said second means is engaged with said first means;   attachment means for attaching said catheter hub to said needle guard prior to engagement of said first means and said second means; and   wherein said needle is insertable into said needle guard and said catheter with said needle guard placed between said needle hub and said catheter hub, said needle slidable relative to said catheter and said needle guard   
     
     
        such that said first means engages said second means. .Iaddend. .Iadd.22. The catheter assembly of claim 21 wherein said needle guard is detachable from said catheter hub after engagement of said first means and said second means. .Iaddend. .Iadd.23. The catheter assembly of claim 21 wherein said first means comprises a change in the diameter of said needle such that said second means is locked on said first means at said change 
     
     
        in said needle diameter. .Iaddend. 24. The catheter assembly of claim 21 wherein said second means comprises expanding means capable of being expanded by the full diameter of said needle.  .Iadd.25. The catheter of claim 21 wherein said attachment means comprises a radially extending flange having a central aperture, and said second means comprises an axially aligned expansion slot passing through said flange, whereby said needle sliding within said needle guard causes said expansion slot to open, such that said attachment means contacts said catheter hub. .Iaddend. .Iadd.26. The catheter of claim 21 wherein said catheter hub includes retaining means connectable to said attachment means prior to 
     
     
        engagement of said first means and said second means. .Iaddend. .Iadd.27. The catheter of claim 26 wherein said retaining means includes a projection extending from said catheter hub and abutting said attachment means. .Iaddend. .Iadd.28. The catheter of claim 21 wherein said attachment means causes said needle guard to be held within said catheter hub. .Iaddend. .Iadd.29. The catheter of claim 21 wherein said attachment means causes axial alignment of said needle guard and said catheter hub, with said needle passing through said catheter and the center of said needle guard. .Iaddend. .Iadd.30. The catheter of claim 21 wherein the proximal portion of said needle guard contains an inner diameter smaller than a portion of the outer diameter of said needle. .Iaddend. .Iadd.31. The catheter assembly of claim 21 wherein said first means comprises a slot located near said needle distal tip. .Iaddend. .Iadd.32. The catheter of claim 21 wherein said distal portion of said needle guard contains a cylindrical portion slightly larger than the outer diameter of said needle. .Iaddend. .Iadd.33. The catheter of claim 32 wherein the proximal portion of said needle guard contains an inner diameter smaller than a portion of the outer diameter of said needle. .Iaddend. .Iadd.34. The catheter of claim 32 wherein said proximal portion of said needle guard contains an expandable central aperture which in its unexpanded condition has an inner diameter which is less than said needle outer diameter. 
     
     
        .Iaddend. 35. The catheter of claim 32 wherein said proximal portion of said needle guard comprises a flange having a central opening aligned with said distal cylindrical portion, and said second means includes an 
     
     
        expansion slot in said flange.  36. The catheter of claim 35 wherein said needle guard is locked to said needle when said flange aperture engages said slot.  .Iadd.37. The catheter of claim 35 wherein said flange aperture diameter is less than the outer diameter of said needle and the full outer diameter of said needle causes said flange aperture to spread and engage said needle. .Iaddend. .Iadd.38. The catheter of claim 21 wherein said attachment means maintains said needle hub in contact with said catheter hub prior to engagement of said first means and said second means. .Iaddend. .Iadd.39. A catheter assembly comprising: a catheter hub;   a catheter attachment to said catheter hub;   a needle hub;   a needle comprising: a distal tip, a proximal end, said needle affixed near its proximal end to said needle hub, and first means for engaging a needle guard;   a needle guard comprising: a proximal portion having second means for engaging said first means, and a distal portion for extending over said needle distal tip when said second means is engaged with said first means;   attachment means for attaching said needle guard to said catheter hub prior to engagement of said first means and said second means;   wherein said needle is insertable into said needle guard and said catheter with said needle guard placed between said needle hub and said catheter hub, said needle slidable relative to said catheter and needle guard; and   wherein said first means comprises a change in said needle diameter such that said second means engages said first means at said needle diameter   
     
     
        change. .Iaddend. .Iadd.40.  The catheter assembly of claim 39 wherein said needle guard is detachable from said catheter hub after engagement of said first means and said second means. .Iaddend. .Iadd.41. The catheter assembly of claim 39 wherein said second means comprises expanding means capable of being expanded by the full diameter of said needle. .Iaddend. .Iadd.42. The catheter of claim 39 wherein said attachment means comprises a radially extending flange having a central aperture, and said second means comprises an axially aligned expansion slot passing through said flange, whereby said needle sliding within said needle guard causes said expansion slot to open, such that said attachment means contacts said catheter hub. .Iaddend. .Iadd.43. The catheter of claim 39 wherein said catheter hub includes retaining means connectable to said attachment means prior to engagement of said first means and said second means. .Iaddend. .Iadd.44. The catheter of claim 43 wherein said retaining means includes a projection extending from said catheter hub and abutting said attachment 
     
     
        means. .Iaddend. .Iadd.45.  The catheter of claim 39 wherein said attachment means causes said needle guard to be held within said catheter hub. .Iaddend. .Iadd.46. The catheter of claim 39 wherein said attachment means causes axial alignment of said needle guard and said catheter hub, with said needle passing through said catheter and the center of said needle guard. .Iaddend. .Iadd.47. The catheter of claim 39 wherein the proximal portion of said needle guard contains an inner diameter smaller than a portion of the outer diameter of said needle. .Iaddend. .Iadd.48. The catheter assembly of claim 39 wherein said first means comprises a slot located near said needle distal tip. .Iaddend. .Iadd.49. The catheter of claim 39 wherein said distal portion of said needle guard contains a cylindrical portion slightly larger than the outer diameter of said needle. .Iaddend. .Iadd.50. The catheter of claim 49 wherein the proximal portion of said needle guard contains an inner diameter smaller than a portion of the outer diameter of said needle. .Iaddend. .Iadd.51. The catheter of claim 49 wherein said proximal portion of said needle guard contains an expandable central aperture which in its unexpanded condition has an inner diameter which is less than said needle outer diameter. 
     
     
        .Iaddend. .Iadd.52.  The catheter of claim 51 wherein said proximal portion of said needle guard comprises a flange having a central opening aligned with said distal cylindrical portion, and said second means includes an expansion slot in said flange. .Iaddend. .Iadd.53. The catheter of claim 51 wherein said needle guard is locked to said needle when said flange aperture engages said slot. .Iaddend. .Iadd.54. The catheter of claim 39 wherein said flange aperture diameter is less than the outer diameter of said needle and the full outer diameter of said needle causes said flange aperture to spread and engage said needle. .Iaddend. .Iadd.55. A catheter assembly comprising: a catheter hub;   a catheter attached to said catheter hub;   a needle hub;   a needle comprising: a distal tip, a proximal end, said needle affixed near its proximal end to said needle hub, and first means for engaging a needle guard;   a needle guard comprising: a proximal portion having second means for engaging said first means, and a distal portion for extending over said needle distal tip when said second means is engaged with said first means;   attachment means for attaching said needle guard to said catheter hub prior to engagement of said first means and said second means;   wherein said needle is insertable into said needle guard and said catheter with said needle guard placed between said needle hub and said catheter hub, said needle slidable relative to said catheter and needle guard; and   wherein said attachment means maintaining said needle hub in contact with said catheter hub prior to attachment of said first means and said second   
     
     
        means. .Iaddend. .Iadd.56.  A catheter assembly comprising: a catheter hub;   a catheter attached to said catheter hub;   a needle hub;   a needle comprising: a distal tip, a proximal end, said needle affixed near its proximal end to said needle hub, and first means for engaging a needle guard;   a needle guard comprising: a proximal portion having second means for engaging said first means, and a distal portion for extending over said needle distal tip when said second means is engaged with said first means;   attachment means for attaching said needle guard to said catheter hub prior to engagement of said first means and said second means;   wherein said needle is insertable into said needle guard and said catheter with said needle guard placed between said needle hub and said catheter hub, said needle slidable relative to said catheter and needle guard; and   wherein said second means comprises a portion of said needle guard with an inner diameter smaller than the outer diameter for a first portion of said needle, such that said second means engages said needle at said needle first portion. .Iaddend. .Iadd.57. The catheter of claim 56 wherein said first means is located at said needle first portion, and said first means   
     
     
        comprises a diametral change in said needle outer diameter. .Iaddend. 58. The catheter of claim 57 wherein said needle diametral change is a narrowing of said needle outer diameter.  .Iadd.59. The catheter assembly of claim 57 wherein said needle guard is detachable from said catheter hub after engagement of said first means and said second means. .Iaddend. .Iadd.60. The catheter assembly of claim 57 wherein said second means comprises expanding means capable of being expanded by the full diameter of said needle. .Iaddend. .Iadd.61. The catheter of claim 57 wherein said catheter hub includes retaining means connectable to said attachment means prior to engagement of said first means and said second means. .Iaddend. .Iadd.62. The catheter of claim 57 wherein said attachment means causes said needle guard to be held within said catheter hub. .Iaddend. .Iadd.63. The catheter of claim 57 wherein said attachment means causes axial alignment of said needle guard and said catheter hub, with said needle passing through said catheter and the center of said needle guard. .Iaddend. .Iadd.64. The catheter of claim 57 wherein said attachment means maintains said needle hub in contact with said catheter hub prior to engagement of said first means and said second means. .Iaddend.