Impedance mediated control of power delivery for electrosurgery
US9277962B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 25, 2011 |
| Grant date | Mar 8, 2016 |
| Priority date | — |
| Expiry date | Sep 9, 2032 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B2018/00875
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A method of controlling electrosurgical power delivery is based on a comparison of sensed tissue impedance to various impedance threshold values. Energy is delivered to tissue in a sealing cycle as a series of pulses. A pulse has a profile with a preset energy starting value that increases at a ramping rate to a preset end value. Sensed impedance data are monitored throughout each pulse and compared to each of an impedance threshold value for RF setpoint, an impedance threshold value for cumulative time, and an impedance threshold value for energy cutback. Based on sensed impedance during a pulse, the profile of a subsequent pulse can be modified. In the event of a high impedance event that reflects low tissue presence, energy may be cutback. A sealing cycle is stopped when a cumulative amount of time with an impedance value over the impedance cumulative time threshold value reaches a limit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.