Trocar

• US 5,261,891 A
• Filed: 02/20/1992
• Issued: 11/16/1993
• Est. Priority Date: 01/15/1991
• Status: Expired due to Term

• Current Assignee: Ethicon Incorporated (Johnson & Johnson)
• Original Assignee: Ethicon Incorporated (Johnson & Johnson)
• Inventors: Brinkerhoff, Ronald J., Parkhurst, Harry C., Vincze, Bela, Mills, Earl J.
• Primary Examiner(s): Hirsch, Paul J.
• Application Number:
  US07/823,810
• Time in Patent Office: 635 Days
• Field of Search: 604/117, 604/164, 604/170, 604/274, 604/273, 604/158, 604/272, 604/165, 606/185
• US Class Current: 604/164.12
• CPC Class Codes: A61B 17/3474 Insufflating needles, e.g. Veress needles
• CPC Class Codes: A61B 17/3496 Protecting sleeves or inner probes; Retractable tips for protecting body piercing guide needles A61M25/0612
• CPC Class Codes: A61B 2090/08021 of the patient or his organs

Abstract

A safety trocar is provided which includes a spring-loaded shield that shields the cutting tip of the obturator after the obturator penetrates tissue. The distal end of the shield is hemispheric in profile and contains slides within cutting tip. The rounded distal end enables the shield to spring forward to shield the cutting tip as soon as the tip perforates the tissue. In other embodiments, positive mechanical means effect shielding.

Claims

1. A trocar comprising:

an obturator having a sharpened tip;

a shield for enclosing said tip, said shield connected to said obturator and movable relative to said obturator;

said tip urged outside said shield by spring means connected to said shield;

placement means comprising a pin and a channel, said pin placed in sliding relationship in said channel;

wherein said channel is placed on one of said obturator and said shield, and said pin is placed on the opposite of said obturator and said shield; and

wherein said channel contains a longitudinal portion for positively urging said pin away from said spring means, and a closure portion connected to said longitudinal portion operable by rotating said shield about said obturator such that said pin is guided within said closure portion to a position restricting longitudinal movement of said shield relative to said obturator.

2. The trocar of claim 1 further comprising a laparoscopic cannula, and said obturator and shield insertable into said cannula;

and

control means connected to said obturator and cannula, and actuable such that said control means cause said obturator tip to be exposed from said shield by motion relative to said shield when said shield and said obturator are placed within said cannula.

3. The trocar of claim 2 wherein said control means further comprise manually operable means connected to said obturator which cause said obturator to slide relative to said shield to an open position to expose said tip from said shield.

4. The trocar of claim 2 wherein said control means are further capable of causing said tip to retract from said open position to a closed position where said tip is enclosed by said shield.

5. The trocar of claim 4 further comprising handle means connected to said obturator and said shield, said handle means extending from said cannula when said obturator and shield are inserted within said cannula, and said control means further comprise push button means movable with said handle means and capable of causing said obturator to slide within said cannula relative to said shield.

6. The trocar of claim 2 said control means further comprising sensor means attached to said shield and said obturator, said sensor means capable of sensing pressure on said obturator or said shield and activating said shield to an open position to expose said tip from said shield.

7. The trocar of claim 6 wherein said control means are further capable of causing said tip to retract from said open position to a closed position where said tip is enclosed by said shield.

8. The trocar of claim 6 further comprising latch means connected to said sensor and said shield and activated by said sensor to hold said shield in said open portion.

9. The trocar of claim 8 wherein said control means, said obturator and said shield are contained within a handle, said handle enabling insertion of said obturator and said shield into said cannula.

10. The trocar of claim 8 wherein said sensor is electromechanical and attached to said obturator tip to sense pressure on said tip.

11. The trocar of claim 1 wherein said placement means is capable of maintaining said obturator tip urged outside said shield.

12. The trocar of claim 1 wherein said closure portion contains a curved section and a lateral section, said pin movable from said longitudinal portion into said curved section by rotation of said shield and into said lateral section by further rotation of said shield such that motion is restricted longitudinally when said jaw is seated in said lateral section.

13. The trocar of claim 1 wherein said obturator contains a hollow cross-section, and said shield insertable into said obturator hollow cross-section.

14. The trocar of claim 13 wherein said shield has a generally blunt end.

15. The trocar of claim 14 wherein said spring means and said obturator are connected to a handle, said handle holding said spring means in place to urge said shield in spaced apart relation to said obturator tip.

16. The trocar of claim 15 further comprising a cannula wherein said shield is placed inside said obturator on said handle and is insertable into said cannula.

17. The trocar of claim 16 wherein said shield is capable of being held by latching means to expose said obturator tip from said cannula.