Translatable outer tube for sealing using shielded lap chole dissector

A surgical instrument, comprising:

• a handle assembly;
• an ultrasonic transducer configured to produce ultrasonic vibrations;
• a shaft coupled to the handle assembly, the shaft comprising:
• an ultrasonic waveguide coupled to the ultrasonic transducer and configured to vibrate at an ultrasonic frequency;
• and
• a slidable lever configured to slide back and forth within the shaft;
• and
• an end effector comprising:
• a blade having a cutting edge configured to cut tissue and a back edge, the blade coupled to the ultrasonic waveguide and configured to vibrate at the ultrasonic frequency to cut the tissue;
• a heating pad comprising a high-friction surface enclosing a portion of the blade or the ultrasonic waveguide and coupled to the slidable lever, wherein a space is defined between the high-friction surface and the blade or the ultrasonic waveguide when the end effector is configured into a cutting configuration;
• wherein, when the end effector is configured into a sealing configuration, the slidable lever is configured to slide proximally toward the handle assembly, causing the high-friction surface to contact the blade or the ultrasonic waveguide , wherein the high-friction surface is configured to generate heat by frictionally coupling ultrasonic vibrations from the blade or the ultrasonic waveguide contacting the high-friction surface, and wherein the back edge of the blade is configured to coagulate tissue based on heat transfer from the high-friction surface to the back edge.

A surgical instrument, comprising:

• a handle assembly;
• an ultrasonic transducer;
• a shaft coupled to the handle assembly, the shaft comprising:
• an ultrasonic waveguide configured to vibrate at an ultrasonic frequency;
• and
• a rotatable inner tube configured to rotate within the shaft;
• and
• an end effector comprising:
• a blade having a cutting edge configured to cut tissue and a back edge, the blade coupled to the ultrasonic waveguide and configured to vibrate at the ultrasonic frequency to cut the tissue;
• a rotatable member coupled to the rotatable inner tube;
• a shielded portion coupled to the rotatable member and enclosing the back edge of the blade;
• a high-friction surface coupled to the shielded portion and positioned between the shielded portion and the back edge of the blade, wherein there is a space between the high-friction surface and the back edge of the blade when the end effector is configured into a cutting configuration;
• wherein, when the end effector is configured into a sealing configuration, the shielded portion is rotated onto the blade based on rotation of the rotatable inner tube, such that the high-friction surface touches the back edge of the blade and is configured to generate heat based on ultrasonic vibrations of the blade rubbing against the high-friction surface, and wherein the shielded portion is configured to coagulate tissue based on heat transfer from the high-friction surface to the shielded portion.