Claims
- 1. A trocar adapted to provide a working channel across a body wall to accommodate a surgical instrument having an outer surface and a distal tip, the trocar comprising:
- a cannula having an axis extending between a distal end and a proximal end of the cannula;
- a housing attached to the cannula at the proximal end of the cannula and forming with the cannula the working channel;
- valve means disposed in the working channel for forming a seal with an outer surface of the instrument and across the working channel;
- a valve adjustment apparatus, at least a portion of which is disposed in the working channel proximally of the valve means, the valve adjustment apparatus being adapted to move axially within said working channel between a first position spaced from the valve means and a second position wherein at least a portion of the valve adjustment apparatus is interposed between the valve means and a portion of the working channel which extends through the valve means, such that the valve means is protected from the instrument when the distal tip of the instrument is inserted therethrough; and
- the valve adjustment apparatus being adapted to be responsive to insertion of the instrument into the working channel to move from the first position to the second position.
- 2. The trocar recited in claim 1 further comprising apparatus for biasing the valve adjustment means to the first position.
- 3. The trocar recited in claim 1 further comprising means defining a guideway for guiding the valve adjustment apparatus during movement of the valve adjustment apparatus between the first position and the second position.
- 4. The trocar recited in claim 3 wherein the guideway is disposed axially of the trocar so that the first position of the valve adjustment apparatus is spaced axially from the second position of the valve adjustment apparatus.
- 5. The trocar recited in claim 1 wherein the valve adjustment apparatus has a conical inner surface adapted to be engaged by the instrument when the instrument is inserted into the working channel.
- 6. The trocar recited in claim 1 wherein the valve adjustment apparatus comprises:
- a wall defining a portion of the working channel which extends through the valve adjustment apparatus;
- a continuous inner surface of the wall having a conical configuration and converging with progressive distal positions along the axis of the cannula; whereby
- the conical inner surface of the wall of the valve adjustment apparatus is adapted to be contacted by the instrument when the instrument is inserted into the working channel.
- 7. The trocar recited in claim 6 wherein the wall of the valve adjustment apparatus is radially expandable to enlarge the working channel through the valve adjustment apparatus to a diameter sufficient to permit passage of the instrument through the valve.
- 8. The trocar recited in claim 7 wherein axial movement of the instrument through the valve adjustment apparatus produces on the valve adjustment apparatus an axial force component tending to move the valve adjustment apparatus axially between the first position and the second position, and a radial force component tending to radially expand the valve adjustment apparatus between the first position and the second position.
- 9. A trocar adapted to provide a working channel across a body wall to accommodate a surgical instrument having a particular diameter, the trocar comprising:
- a cannula defining the working channel along an axis between a distal end and a proximal end of the cannula;
- a housing attached to the cannula at the proximal end of the cannula;
- a first septum valve disposed within the housing and having an orifice with a first diameter which is less than the particular diameter of the instrument;
- a second septum valve disposed within the housing and having an orifice with a second diameter which is less than the particular diameter of the instrument and greater than the first diameter of the first valve; and
- valve adjustment means disposed proximally of the first valve for enlarging the first orifice of the first valve, the valve adjustment means being responsive to insertion of the instrument to move from a first position in proximity to the second valve to a second position in proximity to the first valve.
- 10. The trocar recited in claim 9 wherein the first position is disposed axially of the second position.
- 11. The trocar recited in claim 9 further comprising means for biasing the valve adjustment means to the first position.
- 12. The trocar recited in claim 9 wherein the valve adjustment means is dimensioned and arranged to remain in the first position in response to insertion of a second instrument having a diameter less than the second diameter of the second valve.
- 13. A method for protecting a valve disposed in a trocar having an axis, the trocar having a working channel extending through an orifice in the valve, the method comprising the steps of:
- providing in the trocar a valve adjuster movable from a first position spaced from the valve to a second position in contact with the valve, the valve adjuster in the second position being disposed to enlarge the orifice of the valve;
- inserting an instrument into the working channel of the trocar, the instrument having an elongate shaft and a sharp or puncture prone configuration;
- during the inserting step engaging the valve adjuster at the first position with the instrument;
- moving the valve adjuster axially with the instrument from the first position to the second position; and
- radially expanding the valve adjuster and the valve to enlarge the orifice of the valve.
- 14. The method recited in claim 13 wherein:
- the valve adjuster has a relaxed state and an expanded state;
- the contacting step includes the step of contacting the valve with the valve adjuster in the relaxed state; and
- the expanding step includes the step of moving the valve adjuster to the expanded state with the instrument to enlarge the orifice of the valve.
- 15. The method recited in claim 13 further comprising the step of biasing the valve adjuster to the first position.
- 16. A trocar adapted to provide a working channel across a body wall to accommodate a surgical instrument, the trocar comprising:
- a cannula defining the working channel along an axis extending between a distal end and a proximal end of the cannula;
- a housing attached to the cannula at the proximal end of the cannula;
- valve means disposed in the housing for forming a seal around the instrument and across the working channel;
- a first septum valve included in the valve means and disposed across the working channel, the first septum valve having an orifice with a first diameter;
- a second septum valve included in the valve means and disposed across the working channel, the second septum valve having an orifice with a second diameter greater than the first diameter;
- valve adjustment means for protecting the valve means from the instrument, the valve adjustment means disposed between the first septum valve and the second septum valve and being movable in response to insertion of the instrument into the working channel from a first position in proximity to the second septum valve to a second position in proximity to the first septum valve.
- 17. A trocar adapted to provide a working channel across a body wall to accommodate a surgical instrument having a particular diameter, the trocar comprising:
- a cannula defining the working channel along an axis extending between a distal end and a proximal end of the cannula;
- a housing attached to the cannula at the proximal end of the cannula;
- valve means disposed in the housing for forming a seal around the instrument and across the working channel;
- a septum valve included in the valve means and having an orifice with a diameter which is less than the particular diameter of the instrument;
- valve adjustment means for protecting the valve means from the instrument, the valve adjustment means being responsive to insertion of the instrument into the working channel to move from the first position spaced from the valve means to a second position wherein the valve adjustment means extends at least partially between the instrument and the valve means when the instrument is operatively disposed in the working channel; and
- radially expansible means included in the valve means for engaging the orifice of the septum valve to receive the instrument.
- 18. A method for inserting a surgical instrument through a body wall into a body cavity including the steps of:
- providing a trocar having a cannula, a valve housing defining with the cannula a working channel, a valve disposed along the working channel and having elastomeric characteristics for forming a seal around the instrument, and valve adjuster movable from a first position spaced from the valve to a second position wherein the valve adjuster extends at least partially between the instrument and the valve;
- providing the valve adjuster with a continuous wall having an inner surface defining the working channel through the valve adjuster;
- inserting the instrument into the working channel;
- moving the instrument generally axially through the working channel;
- during the moving step contacting the continuous inner surface of the wall of the valve adjuster with the instrument to produce on the valve adjuster a radial force and an axial force; and
- axially advancing the valve adjuster in response to the axial force of the instrument on the valve adjuster to move the valve adjuster from the first position to the second position.
- 19. The method recited in claim 18 wherein the moving step comprises the step of radially expanding the valve adjuster between the first position and the second position in response to the radial force produced on the valve adjuster by the instrument.
- 20. The method recited in claim 19 further comprising the step of withdrawing the instrument axially to move the valve adjuster proximally, axially from the second position to a third position wherein the valve adjuster is removed from between at least a portion of the valve and the instrument to facilitate formation of the seal between the instrument and the valve.
Parent Case Info
This application is a continuation of application Ser. No. 07/979,835, filed Nov. 23, 1992, now abandoned.
US Referenced Citations (5)
Continuations (1)
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Number |
Date |
Country |
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979835 |
Nov 1992 |
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