US Patent 9737355 Controlling impedance rise in electrosurgical medical devices

Various embodiments are directed to electrosurgical systems for providing an electrosurgical signal to a patient. A control circuit may, for a first application period, apply the electrosurgical signal to first and second electrodes according to a first mode. In the first mode, the control circuit may limit the electrosurgical signal to a first maximum power when the impedance between the first and second electrodes exceeds a first mode threshold. The control circuit may also, for a second application period after the first application period, apply the electrosurgical signal according to a second mode. In the second mode, the control circuit may limit the electrosurgical signal to a second mode maximum power when the impedance between the first and second electrodes exceeds a second mode threshold. The second maximum power may be greater than the first maximum power.