System and Method for Controlling Electrosurgical Output

• US 20110071516A1
• Filed: 09/24/2009
• Published: 03/24/2011
• Est. Priority Date: 09/24/2009
• Status: Abandoned Application

• Current Assignee: Covidien LP (Medtronic Plc)
• Original Assignee: Tyco Healthcare Group LP (Medtronic Plc)
• Inventors: Gregg, William N.
• Application Number:
  US12/566,233
• Publication Number:
  US 20110071516A1
• Time in Patent Office: Days
• US Class Current: 606/34
• CPC Class Codes: A61B 18/1206 Generators therefor
• CPC Class Codes: A61B 18/1233 with circuits for assuring patient safety
• CPC Class Codes: A61B 18/1442 Probes having pivoting end effectors, e.g. forceps
• CPC Class Codes: A61B 2017/00123 and automatic shutdown
• CPC Class Codes: A61B 2018/00702 Power or energy
• CPC Class Codes: A61B 2018/00869 Phase
• CPC Class Codes: A61B 2018/00875 Resistance or impedance

Abstract

An electrosurgical generator for supplying electrosurgical energy to tissue includes sensor circuitry configured to measure a voltage phase and a current phase through tissue and a processing device configured to compare the measured voltage and current phase to generate a real power component. The electrosurgical generator also includes a controller configured to regulate output of the electrosurgical generator based on the real power component and/or a predetermined imaginary impedance of tissue.

Claims

1. An electrosurgical generator for supplying electrosurgical energy to tissue, comprising:

sensor circuitry configured to measure a voltage phase and a current phase through tissue;

a processing device configured to compare the measured voltage and current phase to generate a real power component; and

a controller configured to regulate output of the electrosurgical generator based on at least one of the real power component and a predetermined imaginary impedance of tissue.

2. An electrosurgical generator according to claim 1, wherein the controller is configured to discontinue the output of the electrosurgical generator based on the predetermined imaginary impedance.

3. An electrosurgical generator according to claim 1, wherein the controller is configured to adjust the output of the electrosurgical generator to a predetermined level based on the predetermined imaginary impedance.

4. An electrosurgical generator according to claim 1, wherein the controller is configured to adjust the output of the electrosurgical generator based on an expiration of a predetermined period of time.

5. An electrosurgical generator according to claim 1, wherein the processing device is configured to calculate the real power component based on a difference between the measured voltage phase and current phase.

6. An electrosurgical generator according to claim 1, wherein the real power component corresponds to the output of the electrosurgical generator delivered to a resistive component of tissue.

7. A method for supplying electrosurgical energy to tissue, comprising the steps of:

measuring a voltage phase and a current phase through tissue;

comparing the measured voltage phase and the measured current phase to generate a real power component; and

regulating output of an electrosurgical generator based on at least one of the real power component and a predetermined range between a complex impedance of tissue and a real impedance of tissue.

8. A method according to claim 7, further comprising the step of:

calculating the real power component based on a difference between the measured voltage phase and current phase.

9. A method according to claim 7, further comprising the step of:

discontinuing the output of the electrosurgical generator based on the predetermined range between the complex and real tissue impedance.

10. A method according to claim 7, further comprising the step of:

adjusting the output of the electrosurgical generator to a predetermined level based on the predetermined range between the complex and real tissue impedance.

11. A method according to claim 7, further comprising the step of:

regulating the output of the electrosurgical generator based on an ability of the electrosurgical generator to output energy at a pre-determined level.

12. A method for supplying electrosurgical energy to tissue, comprising the steps of:

measuring a voltage phase and a current phase through tissue;

calculating a difference between the voltage phase and the current phase;

calculating a real power component of the electrosurgical energy based on at least one of the voltage phase, the current phase, and a difference between the voltage and current phases;

regulating output of the electrosurgical generator based on the real power component; and

adjusting the output of the electrosurgical generator to a pre-determined safeguard level based on a detected fault condition.

13. A method according to claim 12, wherein the detected fault condition is a predetermined imaginary impedance of tissue.

14. A method according to claim 12, further comprising the step of:

discontinuing the output of the electro surgical generator based on the detected fault condition.