System and method for return electrode monitoring

• US 20090036884A1
• Filed: 08/01/2007
• Published: 02/05/2009
• Est. Priority Date: 08/01/2007
• Status: Active Grant

• Current Assignee: Covidien LP (Medtronic Plc)
• Original Assignee: Covidien LP (Medtronic Plc)
• Inventors: Gregg, William N., Rick, Kyle R.
• Granted Patent: US 8,801,703 B2
• Time in Patent Office: Days
• US Class Current: 606/35
• CPC Class Codes: A61B 18/1233 with circuits for assuring patient safety
• CPC Class Codes: A61B 18/16 Indifferent or passive electrodes for grounding
• CPC Class Codes: A61B 2017/00026 Conductivity or impedance, e.g. of tissue
• CPC Class Codes: A61B 2017/00119 alarm; indicating an abnormal situation
• CPC Class Codes: A61B 2018/00666 using a threshold value
• CPC Class Codes: A61B 2018/0072 Current
• CPC Class Codes: A61B 2018/00755 Resistance or impedance
• CPC Class Codes: A61B 2018/00827 Current
• CPC Class Codes: A61B 2018/00875 Resistance or impedance
• CPC Class Codes: A61B 2018/1467 using more than two electrodes on a single probe
• CPC Class Codes: A61B 2018/162 located on the probe body
• CPC Class Codes: A61B 2018/165 Multiple indifferent electrodes

Abstract

A system for determining probability of tissue damage is disclosed. The system includes a plurality of return electrodes adhered to a patient and adapted to couple to an electrosurgical generator configured to generate an electrosurgical current. The system also includes a current monitor and a switching component connected in series with each of the plurality of the return electrodes. The current monitor being configured to measure the electrosurgical current passing therethrough. The system further includes a processor coupled to each of the current monitors and the switching components. The processor is configured to determine the balance of a current load among the plurality of the return electrodes and configured to control each of the switching components to adjust the current passing through each of the return electrodes to balance the current load.

Claims

1. A system for determining probability of tissue damage, the system comprising:

a plurality of return electrodes adhered to a patient and adapted to couple to an electrosurgical generator configured to generate an electrosurgical current;

a current monitor and a switching component connected in series with each of the plurality of the return electrodes, the current monitor being configured to measure the electrosurgical current passing therethrough; and

a processor coupled to each of the current monitors and the switching components, the processor configured to determine the balance of a current load among the plurality of the return electrodes and configured to control each of the switching components to adjust the current passing through each of the return electrodes to balance the current load.

2. The system according to claim 1, wherein the processor is further configured to determine the balance of the current load by comparing the current passing through each of the plurality of the return electrodes with an average current.

3. The system according to claim 1, wherein the switching component is configured to be operated via a pulse width modulated control signal.

4. The system according to claim 1, wherein the switching component is configured to adjust the current by increasing the impedance of the return electrode.

5. The system according to claim 4, wherein the switching component is selected from the group consisting of a relay, a resistor network, a variable capacitor and a transformer coupled load.

6. The system according claim 1, wherein the switching component adjusts the current by opening a circuit of the at least one return electrode.

7. The system according to claim 6, wherein the circuit of the at least one return electrode is opened for at least a time-off period.

8. The system according to claim 7, wherein the processor is configured to calculate the time-off period as a function of the electrosurgical current measured by the current monitor.

9. The system according claim 1, further comprising an impedance sensor coupled to each of the plurality of the return electrodes.

10. The system according to claim 1, wherein the switching component is selected from the group consisting of a relay and a transistor.

11. A method for determining probability of tissue damage, the method comprising:

providing a plurality of return electrodes adhered to a patient and adapted to couple to an electrosurgical generator that is configured to generate an electrosurgical current, wherein a current monitor and a switching component are connected in series with each of the plurality of the return electrodes;

measuring the electrosurgical current passing through each of a plurality of the return electrodes;

determining the balance of a current load among the plurality of the return electrodes; and

controlling each of the switching components to adjust the current passing through each of the return electrodes to balance the current load.

12. The method according to claim 11, wherein the step of determining the balance of a current load further includes the step of comparing the current passing through each of the plurality of the return electrodes.

13. The method according to claim 11, wherein the switching component of the providing step is configured to operate via a pulse width modulated control signal.

14. The method according to claim 11, wherein the step of controlling each of the switching components further includes the step of adjusting the current by increasing the impedance of the return electrode.

15. The method according to claim 14, wherein the switching component of the providing step is selected from the group consisting of a resistor network, a variable capacitor, and a transformer coupled load.

16. The method according to claim 11, wherein the switching component of the providing step is selected from the group consisting of a relay and a transistor.

17. The method according to claim 11, wherein the step of controlling each of the switching components further includes the step of opening a circuit of at least one return electrode.

18. The method according to claim 11, wherein each of the plurality of the return electrodes of the providing step is coupled to an impedance sensor.