Impedance monitoring apparatus, system, and method for ultrasonic surgical instruments

摘要

In one general aspect, various embodiments are directed to a surgical instrument that can supply mechanical energy and electrical energy to an end effector of the surgical instrument. The surgical instrument comprises an ultrasonic generator module coupled to an ultrasonic drive system, which comprises an ultrasonic transducer coupled to a waveguide and an end effector coupled to the waveguide. The ultrasonic drive system is configured to resonate mechanically at a resonant frequency to generate a first ultrasonic drive signal. An electronic circuit is coupled to the ultrasonic generator module to monitor an electrical characteristic of the ultrasonic drive system. A processor is coupled to the electronic circuit to control the ultrasonic drive signal in response to the monitored electrical characteristic of the ultrasonic drive system.

主权项

1. A method of controlling a surgical instrument, the method comprising:
generating a first ultrasonic drive signal by an ultrasonic generator coupled to an ultrasonic drive system, wherein the first ultrasonic drive signal has a first frequency f1, wherein the ultrasonic drive system comprises an ultrasonic transducer coupled to a waveguide and an end effector coupled to the waveguide, and wherein the ultrasonic drive system is configured to resonate mechanically at a resonant frequency; operating the ultrasonic transducer at the first ultrasonic drive signal for a first period; monitoring an electrical characteristic; controlling the ultrasonic generator in response to the monitored electrical characteristic, wherein the ultrasonic generator is controlled based on a predetermined function responsive to the monitored electrical characteristic, wherein the predetermined function comprises a step function, wherein the first ultrasonic drive signal operates the end effector to separate a muscle layer from a tissue section; generating a second ultrasonic drive signal by the ultrasonic generator, wherein the second ultrasonic drive signal has a second frequency f0, wherein the first frequency f1 and the second frequency f0 are different, and wherein the second ultrasonic drive signal operates the end effector to cut and seal the tissue section; and operating the ultrasonic transducer at the second drive signal for a second period, wherein the first period and the second period are continuous, and wherein the first period and the second period are determined by the predetermined function.