Trocar and cannula
First Claim
1. A shielded obturator comprising:
- (a) an obturator sheath having a distal end and a proximate end;
(b) a handle mounted to the proximate end of said obturator sheath;
(c) a substantially planar pointed blade on the distal end of the obturator sheath;
(d) a shield slideably mounted relative to the obturator sheath and moveable between an extended protective position and a retracted unprotected position; and
(e) a biasing means tending to bias the shield into the extended protective position.
4 Assignments
0 Petitions
Accused Products
Abstract
A trocar is formed from a cannula and an interfitting obturator for penetrating body cavity walls in laparoscopic and endoscopic surgery. The obturator is provided with an improved piercing tip having a pointed blade and an improved locking shield design. The locking mechanism must be actuated before the shield will retract to expose the piercing tip. The shield is located inside the obturator sheath and provides faster coverage of the piercing tip after the body cavity wall has been penetrated. The cannula has an improved thread design to more easily and securely hold the cannula in the incision of the body cavity wall. A one piece inner housing is used in the cannula to reduce the need for welding to prevent gas leakage. The cannula also has improved seals to maintain insufflation of the body cavity and an automatic insufflation valve to facilitate connection to an external gas supply. Reducing fittings may also be used on the cannula to allow the insertion of endoscopic instruments of lesser diameter than the obturator.
279 Citations
19 Claims
-
1. A shielded obturator comprising:
-
(a) an obturator sheath having a distal end and a proximate end; (b) a handle mounted to the proximate end of said obturator sheath; (c) a substantially planar pointed blade on the distal end of the obturator sheath; (d) a shield slideably mounted relative to the obturator sheath and moveable between an extended protective position and a retracted unprotected position; and (e) a biasing means tending to bias the shield into the extended protective position. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. A trocar comprising:
-
(a) a cannula with a housing and a cannula tube, the cannula tube having a lumen of sufficient diameter to receive an obturator sheath; (b) a shielded obturator having a handle, an obturator sheath interfitting in the lumen of the cannula tube and a substantially planar pointed blade, said obturator sheath having a proximal end joined to said handle and also having a distal end on which the substantially planar pointed blade is mounted; (c) a shield slideably mounted relative to the obturator sheath and moveable between an extended protective position and a retracted unprotected position; (d) a biasing means tending to bias the shield into the extended protective position. - View Dependent Claims (11, 12, 13, 14, 15, 16, 17, 18)
-
-
19. A method of using a trocar to penetrate a body wall comprising the steps of:
-
i) providing a trocar having; (a) a cannula with a housing and a cannula tube containing a lumen of sufficient diameter to receive a obturator sheath; (b) a shielded obturator having a handle, an obturator sheath interfitting with the lumen of the cannula tube, said obturator sheath having a proximate end connected to said handle and a distal end, and a substantially planar pointed blade mounted on the distal end of the obturator sheath; (c) a shield slideably mounted relative to the obturator sheath and moveable between an extended position and a retracted position; (d) a biasing means tending to bias the shield into said extended position; (e) a latch means having a locked position in which the shield is locked in its extended position and an actuated position in which the shield may be forced into its retracted position ii) actuating said latch means; iii) urging said cannula tube and pointed blade against the body wall to be penetrated, whereby said shield is pushed into said retracted position by the body wall to expose said substantially planar pointed blade to penetrate the body wall and said latch means is biased to automatically resume locking position upon return of the shield to said extended protective position.
-
Specification