Method of vascular tissue sealing pressure control

• US 6,039,733 A
• Filed: 06/25/1998
• Issued: 03/21/2000
• Est. Priority Date: 09/19/1995
• Status: Expired due to Term

• Current Assignee: Covidien AG (Medtronic Plc)
• Original Assignee: Valleylab Inc. (Medtronic Plc)
• Inventors: Ryan, Thomas P., Lands, Michael J., Buysse, Steven P., Lukianow, S. Wade, Kennedy, Jenifer S., Loeffler, Donald R.
• Primary Examiner(s): ROLLINS, ROSILAND STACIE
• Application Number:
  US09/104,728
• Time in Patent Office: 635 Days
• Field of Search: 606/38, 606/32, 606/40, 606/41, 606/42, 606/50, 606/51, 606/52, 606/191, 606/213, 606/215, 606/216, 606/118, 606/151, 606/142, 606/143, 128/898, 607/115, 607/116, 600/547, 600/549
• US Class Current: 606/40
• CPC Class Codes: A61B 17/29 Forceps for use in minimally invasive surgery
• CPC Class Codes: A61B 18/1445 at the distal end of a shaft, e.g. forceps or scissors at the end of a rigid rod
• CPC Class Codes: A61B 2017/2932 Transmission of forces to jaw members
• CPC Class Codes: A61B 2018/00666 using a threshold value
• CPC Class Codes: A61B 2018/00702 Power or energy
• CPC Class Codes: A61B 2018/00875 Resistance or impedance
• CPC Class Codes: A61B 90/03 Automatic limiting or abutting means, e.g. for safety

Abstract

A clamping force mechanism and its method of use with electrosurgery allow a user to seal and/or join patient'"'"'s particular vascular tissue; the mechanism is elongate with user and patient ends. An actuator is at the user end and the effectors are at the patient end. Each effector has a face of an area to contact the particular vascular tissue. A lost motion connection transfers user actuation to the effectors to hold a predetermined clamping force during electrosurgical tissue sealing. A yielding member in the loss motion connection clamps the particular tissue between the faces with a predetermined force. The yielding member is a spring, slip clutch or hydraulic coupling possibly near the actuator. An active electrode is carried on one end effector and a return electrode contacts the tissue so an electrosurgical energy supply connected thereacross delivers energy therebetween. A feedback circuit responds to parameters of energy delivered to tissue. A temperature sensor on one face and an impedance monitor respond to energy delivered. A control applies energy to held tissue to seal and/or join it. The method transfers user actuation of the effectors with the lost motion connection, maintains clamping force while sealing and applying electrosurgical energy to seal and/or join held tissue. Energy is applied to a temperature or an impedance. The method shifts the yielding member so the opposing faces clamp the particular tissue therebetween with the force from the spring via a transfer rod or by the hydraulic coupling or the slip clutch for a range of pressure.

Claims

1. A method for surgically clamping and sealing tissue, comprising the steps of:

providing an instrument comprising;

an elongated support having a user end and a patient end;

an actuator for operation by a user;

a pair of end effectors proximal to said patient end wherein at least one of said pair of end effectors is attached to said actuator to control the relative motion between said pair of effectors;

a lost motion connection between at least one of said pair of end effectors and said actuator;

an active electrode disposed on one of said pair of end effectors;

a return electrode adapted for contact with the tissue and which completes an electrical circuit between said active and return electrodes;

an electrosurgical energy supply for transmitting electrosurgical energy through said electrical circuit and across said active and return electrodes when the tissue is clamped between said pair of end effectors; and

a control associated with said electrosurgical energy supply to regulate an amount of electrosurgical energy to the tissue in response to the application of the predetermined clamping force;

positioning the tissue between said pair of end effectors;

transferring user manipulation of said actuator to at least one of said pairs of end effectors through said lost motion connection so as to maintain a predetermined clamping force irrespective of the user manipulation during sealing of the tissue between said pair of end effectors;

maintaining a predetermined clamping force during sealing of the tissue between said pair of end effectors; and

applying electrosurgical energy for sealing the held tissue in response to the application of the predetermined clamping force to the tissue between said pair of effectors.

2. A method according to claim 1 wherein the providing step includes providing a feedback circuit having a temperature sensor carried on one of said pair of end effectors.

3. A method according to claim 2 wherein the step of applying electrosurgical energy responds to the temperature of the tissue held between said pair of end effectors during delivery of electrosurgical energy.

4. A method according to claim 1 wherein the step of providing includes providing a feedback circuit having an impedance monitor electrically connected to said electrosurgical energy supply.

5. A method according to claim 4 wherein the step of applying electrosurgical energy responds to the impedance of the tissue between said active and return electrodes during delivery of said electrosurgical energy.

6. A method according to claim 1 wherein said step of providing includes providing a lost motion connection comprising a yielding member and the step of maintaining the predetermined clamping force during sealing of the tissue includes shifting said yielding member with said actuator so that said pair of end effectors clamp the tissue therebetween with the predetermined clamping force from the yielding member.

7. A method according to claim 6 wherein said step of providing includes providing a lost motion connector comprising a yielding member having a spring.

8. A method according to claim 6 wherein said step of providing includes providing a lost motion connector comprising a yielding member having a hydraulic coupling.

9. A method according to claim 6 wherein said step of providing includes providing a lost motion connector comprising a yielding member having a slip clutch.

10. A method according to claim 6 wherein the step of maintaining the predetermined clamping force during sealing of the tissue includes using a clamping pressure applied to the tissue in the range of 300 to 2500 grams.

11. A method for surgically clamping and sealing tissue, comprising the steps of:

providing an instrument comprising;

an elongated support having a user end and a patient end;

an actuator for operation by a user and a pair of end effectors proximal to said patient end for holding and sealing the tissue wherein at least one of said pair of end effectors is attached to said actuator to control the relative motion between said pair of effectors;

a lost motion connection which maintains a predetermined clamping force on said effectors irrespective of a user'"'"'s manipulation during sealing of the tissue between said pair of end effectors;

positioning the tissue between said pair of end effectors;

transferring user manipulation of said actuator to at least one of said pair of end effectors through said lost motion connection to clamp the tissue with said predetermined clamping force irrespective of the user'"'"'s manipulation of the instrument;

maintaining a predetermined clamping force during sealing of the tissue between said pair of end effectors with the lost motion connection irrespective of the user'"'"'s manipulation of the instrument; and

applying an amount of electrosurgical energy to seal the tissue held between said pair of end effectors.

12. A method according to claim 11 wherein the providing step includes providing a instrument comprising an active electrode disposed on one of said pair of end effectors and a return electrode adapted to be disposed proximal to the tissue and the step of applying an amount electrosurgical energy applies an amount of electrosurgical energy between said active and return electrodes to seal the tissue.

13. A method according to claim 11 wherein the providing step includes providing a feedback circuit having a temperature sensor carried on one of said pair of end effectors.

14. A method according to claim 13 wherein the step of applying said amount of electrosurgical energy is responsive to the temperature of the tissue held between said pair of end effectors during application of said amount of electrosurgical energy.

15. A method according to claim 12 wherein the step of providing includes providing a feedback circuit having an impedance monitor and the step of applying an amount of electrosurgical energy is responsive to a parameter of impedance of the tissue held between said active and return electrodes during delivery of the amount of electrosurgical energy.

16. A method according to claim 11 wherein said step of providing includes providing a lost motion connection comprising a yielding member and the step of maintaining the predetermined clamping force during sealing of the tissue includes shifting said yielding member with said actuator so that said pair of end effectors clamp the tissue therebetween with the predetermined clamping force from said yielding member.

17. A method according to claim 11 wherein said step of providing includes providing a lost motion connector comprising a yielding member having a spring.

18. A method according to claim 11 wherein said step of providing includes providing a lost motion connector comprising a yielding member having a hydraulic coupling.

19. A method according to claim 11 wherein said step of providing includes providing a lost motion connector comprising a yielding member having a slip clutch.

20. A method according to claim 11 wherein the step of maintaining the predetermined clamping force during sealing of the tissue includes using a clamping pressure applied to the tissue in the range of 300 to 2500 grams.