Devices and techniques for cutting and coagulating tissue

Patent metadata

Field	Value
Publication number	US-10022568-B2
Application number	US-201514810318-A
Country	US
Kind code	B2
Filing date	Jul 27, 2015
Priority date	Aug 6, 2008
Publication date	Jul 17, 2018
Grant date	Jul 17, 2018

Abstract

Various embodiments are directed to a method of driving an end effector coupled to an ultrasonic drive system of a surgical instrument. In accordance with the method, a generator is configured to generate at least one time varying electrical signal having a resonant frequency, monitor the resonant frequency of the at least one electrical signal, calculate a frequency slope between frequency data points of the time varying electrical signal, where the frequency slope is the change in resonant frequency over time, compare the frequency slope to a threshold frequency slope, and trigger a first response of the generator when the frequency slope crosses the threshold frequency slope.

First claim

The invention claimed is:

1. A method of driving an end effector coupled to an ultrasonic drive system of a surgical instrument, the method comprising:
generating, by a generator, at least one time-varying electrical signal having a resonant frequency;
monitoring, by the generator, the resonant frequency of the at least one time-varying electrical signal;
calculating, by the generator, a frequency slope between frequency data points of the time varying electrical signal, where the frequency slope is a change in resonant frequency over time;
comparing, by the generator, the frequency slope to a frequency slope threshold; and
triggering, by the generator, a first response of the generator when the frequency slope crosses the frequency slope threshold.

2. The method of claim 1 , comprising:
comparing, by the generator, the frequency slope to the frequency slope threshold; and
triggering, by the generator, a second response of the generator when the frequency slope crosses the frequency slope threshold.

3. The method of claim 2 , comprising:
determining, by the generator, when the frequency slope is less than the frequency slope threshold;
incrementing, by the generator, a timer when the frequency slope is less than the frequency slope threshold;
determining, by the generator, when the timer is greater than a required trigger time; and
setting a logic condition when the timer is greater than the required trigger time.

4. The method of claim 3 , comprising:
incrementing, by the generator, the timer when the resonant frequency is less than a resonant frequency threshold and the frequency slope is less than the frequency slope threshold.

5. The method of claim 2 , comprising:
comparing, by the generator, the frequency slope to a cross-back frequency slope threshold, wherein the cross-back frequency slope threshold is the frequency slope threshold above which a triggered response stops.

6. A method of driving an end effector coupled to an ultrasonic drive system of a surgical instrument, the method comprising:
receiving, by a generator, a frequency slope threshold;
monitoring, by the generator, a frequency slope of the ultrasonic drive system;
comparing, by the generator, the frequency slope of the ultrasonic drive system with the frequency slope threshold; and
incrementing, by the generator, a timer when the frequency slope is less than the frequency slope threshold.

7. The method of claim 6 , further comprising:
receiving, by the generator, a required time before trigger parameter;
receiving, by the generator, a timer value from the timer;
comparing, by the generator, the required time before trigger parameter and the timer value;
setting, by the generator, a condition set latch when the timer value is greater than the required time before trigger parameter and indicating that a predetermined condition has set been met; or
resetting, by the generator, the condition set latch when the timer value is less than or equal to the required time before trigger parameter.

8. The method of claim 6 further comprising:
resetting, by the generator, the timer when the frequency slope is greater than the frequency slope threshold.

9. The method of claim 8 , further comprising:
determining, by the generator, when a cross-back frequency slope latch is set; and
indicating that a predetermined condition set has not been met when the cross-back frequency slope latch is not set.

10. The method of claim 9 , further comprising:
receiving, by the generator, a minimum latch time parameter for a condition set latch;
receiving, by the generator, a cross-back frequency slope threshold parameter;
receiving, by the generator, an indication that at least one of the condition set latch or the cross-back frequency slope latch is set;
comparing, by the generator, a latched time of the condition set latch with the minimum latch time parameter for the condition set latch;
comparing, by the generator, the frequency slope with the cross-back frequency slope threshold parameter; and
indicating, by the generator, that a predetermined condition set has been met when the frequency slope is less than the cross-back frequency slope threshold parameter.

11. The method of claim 10 , further comprising:
resetting, by the generator, a timer latch; and
indicating, by the generator, that a predetermined condition set has not been met when the frequency slope is greater than the cross-back frequency slope threshold parameter.

12. A generator configured to drive an end effector coupled to an ultrasonic drive system of a surgical instrument, the generator comprising:
a processor;
a timer circuit coupled to the processor;
a timer latch coupled to the processor;
a condition set latch coupled to the processor; and
a memory coupled to the processor, wherein the memory includes machine executable instructions that when executed by the processor cause the processor to:
receive a frequency slope threshold;
monitor a frequency slope of the ultrasonic drive system;
compare the frequency slope of the ultrasonic drive system with the frequency slope threshold; and
increment the timer circuit when the frequency slope is less than the frequency slope threshold.

13. The generator of claim 12 , wherein the machine executable instructions, when executed by the processor, cause the processor to:
receive a required time before trigger parameter;
receive a timer value from the timer circuit;
compare the required time before trigger parameter and the timer value;
set the condition set latch when the timer value is greater than the required time before trigger parameter and indicate that a predetermined condition has not been met; or
reset the condition set latch when the timer value is less than or equal to the required time before trigger parameter.

14. The generator of claim 12 , wherein the machine executable instructions, when executed by the processor, cause the processor to:
reset the timer circuit when the frequency slope is greater than the frequency slope threshold.

15. The generator of claim 14 , wherein the machine executable instructions, when executed by the processor, cause the processor to:
indicate a cross-back frequency slope latch is set; and
indicate that a predetermined condition set has not been met when the cross-back frequency slope latch is not set.

16. The generator of claim 15 , wherein the machine executable instructions, when executed by the processor, cause the processor to:
receive a minimum latch time parameter for the condition set latch;
receive a cross-back frequency slope threshold parameter;
receive an indication that the cross-back frequency slope latch is set;
compare the frequency slope with the cross-back frequency slope threshold parameter; and
indicate that a predetermined condition set has been met when the frequency slope is less than the cross-back frequency slope threshold parameter.

17. The generator of claim 15 , wherein the machine executable instructions, when executed by the processor, cause the processor to:
reset the timer latch; and
indicate that the predetermined condition set has not been met when the frequency slope is greater than the cross-back frequency slope threshold parameter.

Assignees

• Ethicon Llc

Inventors

• Messerly Jeffrey D
• Wiener Eitan T
• Noyes Brian T
• Aldridge Jeffrey L
• Giordano James R
• Beetel Iii Robert J
• Abbott Daniel J
• Stulen Foster B
• Miller Matthew C
• Voegele Aaron C
• Wiley Jeffrey P
• Price Nathan J
• Price Daniel W
• Koch Jr Robert L

Classifications

• A61B2018/00845

  Frequency · CPC title

• A61B2017/00176

  Two pulses, e.g. second pulse having an effect different from the first one · CPC title

• A61B2017/00973

  pedal-operated · CPC title

• A61B5/053

  Measuring electrical impedance or conductance of a portion of the body · CPC title

• A61B2017/320094

  additional movable means performing clamping operation · CPC title