Surgical tool having electrocautery energy supply conductor with inhibited current leakage

A surgical instrument for use with a robotic surgical system, the instrument comprising:

• an elongate shaft having a proximal end and a distal end and defining an internal longitudinally extending passage, the distal end of the shaft being configured to permit insertion through a minimally invasive incision in a body of a patient;
• an electrocautery end effector disposed at the distal end of the shaft;
• an interface disposed at the proximal end of the shaft, the interface removably connectable to the robotic surgical system;
• a conductor extending from the interface and electrically communicating with at least a portion of the end effector so as to deliver electrical energy to tissue engaged by the end effector;
• an insulative sleeve disposed over the conductor;
• a sealed insulation tube extending within the passage and over the insulated conductor, wherein a separation is maintained between the sealed insulation tube and the insulated conductor, the separation comprising a low dielectric constant material;
• and
• at least two o-rings between the insulation tube and the insulated conductor, a first o-ring positionable at a proximal end of the insulation tube and a second o-ring positionable at a distal end of the insulation tube.

A robotical surgical system comprising:

• a robotic arm having an instrument holder;
• an electrocautery instrument detachably mountable on the instrument holder, the electrocautery instrument having a proximal portion for engaging the instrument holder, an elongate shaft extending from the proximal portion to a distal end and defining an internal longitudinally extending passage, an electrocautery end effector coupleable to the distal end of the shaft, a conductor electrically communicating with at least a portion of the end effector so as to deliver electrical energy to tissue engaged by the end effector, the conductor coupled to an electrical connector on the proximal portion, and a sealed insulation tube extending within the passage and over the conductor, wherein a separation is maintained between the sealed insulation tube and the conductor;
• and
• an electrosurgical generator detachably connected to the connector of the proximal portion so as to transmit electrosurgical energy to the electrocautery end effector.

A method for performing a robotic surgical procedure, the method comprising:

• connecting a surgical instrument to a robotic surgical system, the surgical instrument having an elongate shaft, at one end of which an electrocautery end effector is disposed;
• positioning, with the robotic surgical system, the end effector through an entry port in a patient body and in contact with tissue at a surgical site;
• and
• delivering electrical energy to tissue engaged by the end effector while preventing unintended capacitive coupling between the shaft and the patient.

An electrosurgical instrument, the instrument comprising:

• an elongate shaft having a proximal end and a distal end and defining an internal longitudinally extending passage;
• an electrocautery end effector disposed at the distal end of the shaft, wherein at least the end effector and distal end of the shaft are configured to be insertable through a minimally invasive surgical incision;
• a user-controllable interface disposed at the proximal end of the shaft;
• a conductor extending from the interface to the end effector so as to deliver electrical energy to tissue engaged by the end effector;
• and
• a sealed insulation tube extending within the passage and over the conductor, wherein a separation is maintained between the sealed insulation tube and the conductor.