Electrosurgical apparatus for laparoscopic and like procedures

An electrosurgical apparatus for use with an electrosurgical generator comprising:

• a trocar cannula having a tubular passage for providing a conduit through a patient's skin where the trocar cannula has a proximal end and a distal end;
• a tubular conductive shield having an inner surface and an outer surface and being removably insertable to an inserted position through the trocar cannula conduit, said shield having a distal end and a proximal end;
• an active electrode probe having a tip and being adapted for connection to said electrosurgical generator and extending through the tubular conductive shield for effecting at the tip thereof an electrosurgical procedure within a patient's body where, when the tubular shield is in the inserted position thereof, the shield surrounds and is electrically insulated from the active probe from at least (a) a proximal point prior to the distal end of the trocar cannula to (b) a distal point distal to the distal end of the trocar cannula and in proximity to the tip of the active probe;
• at least one layer of electrical insulation disposed between the active probe and the inner surface of the tubular conductive shield;
• an electrical terminal connected to the shield and adapted for connecting the shield to a reference potential;
• whereby any abnormal condition which causes current to flow in said shield from said active probe is conducted to said reference potential to thus lessen a risk of patient injury;
• and
• monitor circuitry connected between said electrical terminal and said reference potential where the impedance between said electrical terminal and said reference potential is not more than about twenty ohms, said monitor circuitry being responsive to current in the shield to determine whether said abnormal condition exists.

A safety shield system for use with a laparoscopic electrosurgical apparatus including a trocar cannula having a tubular passage for providing a conduit through a patient's skin to a peritoneal cavity of the patient, the trocar cannula having a proximal end and a distal end, an electrosurgical generator and an active electrode probe having a tip and being adapted for connection to said electrosurgical generator and extending through the trocar cannula for effecting at the tip thereof an electrosurgical procedure within the peritoneal cavity, said safety shield comprising

• a tubular conductive shield having an inner surface and an outer surface a distal end and a proximal end and being removably insertable to an inserted position through the trocar cannula, and where, when the tubular shield is in the inserted position thereof, the shield surrounds, and is electrically insulated from, the active probe from at least (a) a proximal point prior to the distal end of the trocar cannula to (b) a distal point distal to the distal end of the trocar cannula and in proximity to the tip of the active probe;
• an electrical terminal connected to the shield and adapted for connecting the shield to a reference potential;
• whereby any abnormal condition which causes current to flow in said shield from said active probe is conducted to said reference potential to thus lessen a risk of patient injury;
• and
• monitor circuitry connected between said electrical terminal and said reference potential where the impedance between said electrical terminal and said reference potential is not more than about twenty ohms, said monitor circuitry being responsive to current in the shield to determine whether said abnormal condition exists.

A safety shield system for use with an electrosurgical apparatus including a trocar cannula having a tubular passage for providing a conduit through a patient's skin where the trocar cannula has a proximal end and a distal end, an electrosurgical generator, and an active electrode probe having a tip and being adapted for connection to said electrosurgical generator and extending through the trocar cannula for effecting at the tip thereof an electrosurgical procedure, said safety shield comprising

• a tubular conductive shield having an inner surface and an outer surface a distal end and a proximal end and being removably insertable to an inserted position through the trocar cannula, and where, when the tubular shield is in the inserted position thereof, the shield surrounds, and is electrically insulated from, the active probe from at least (a) a proximal point prior to the distal end of the trocar cannula to (b) a distal point distal to the distal end of the trocar cannula and in proximity to the tip of the active probe;
• an electrical terminal disposed on the shield and adapted for connecting the shield to a reference potential;
• whereby any abnormal condition which causes current to flow in said shield from said active probe is conducted to said reference potential to thus lessen a risk of patient injury;
• and
• monitor circuitry connected between said electrical terminal and said reference potential where the impedance between said electrical terminal and said reference potential is not more than about twenty ohms, said monitor circuitry being responsive to current in the shield to determine whether said abnormal condition exists.

An electrosurgical apparatus for use with an electrosurgical generator comprising:

• a handpiece having a tubular passage extending therethrough, the handpiece having a proximal end and a distal end;
• a tubular conductive shield having an inner surface and an outer surface and extending at least partially through the handpiece passage, said shield having a distal end and a proximal end;
• an active electrode probe having a tip and being adapted for connection to said electrosurgical generator and extending through the tubular conductive shield for effecting at the tip thereof an electrosurgical procedure where the shield surrounds the active probe from at least (a) a proximal point prior to the distal end of the handpiece to (b) a distal point distal to the distal end of the handpiece and in proximity to the tip of the active probe;
• at least one layer of electrical insulation disposed between the active probe and the inner surface of the tubular conductive shield;
• an electrical terminal connected to the shield and adapted for connecting the shield to a reference potential;
• whereby any abnormal condition which causes current to flow in said shield from said active probe is conducted to said reference potential to thus lessen a risk of patient injury;
• and
• monitor circuitry connected between said electrical terminal and said reference potential where the impedance between said electrical terminal and said reference potential is not more than about twenty ohms, said monitor circuitry being responsive to current in the shield to determine whether said abnormal condition exists.

An electrosurgical apparatus for use with an electrosurgical generator comprising:

• an outer member;
• a tubular conductive shield having an inner surface and an outer surface and being mounted with respect to and extending at least partially through the outer member;
• an active electrode probe having a tip and being adapted for connection to said electrosurgical generator and being mounted with respect to and extending through the tubular conductive shield for effecting at the tip thereof an electrosurgical procedure;
• at least one layer of electrical insulation mounted between the active probe and the inner surface of the tubular conductive shield;
• an electrical terminal connected to the shield and adapted for connecting the shield to a reference potential;
• whereby any abnormal condition which causes current to flow in said shield from said active probe is conducted to said reference potential to thus lessen a risk of patient injury;
• and
• monitor circuitry connected between said electrical terminal and said reference potential where the impedance between said electrical terminal and said reference potential is not more than about 20 ohms, said monitor circuitry being responsive to current in the shield to determine whether said abnormal condition exists.

An electrosurgical apparatus for use with an electrosurgical generator comprising:

• a tubular conductive shield having an inner surface and an outer surface;
• an active electrode probe having a tip and being adapted for connection to said electrosurgical generator and being mounted with respect to and extending through the tubular conductive shield for effecting at the tip thereof an electrosurgical procedure;
• at least one layer of electrical insulation mounted between the active probe and the inner surface of the tubular conductive shield;
• an electrical terminal connected to the shield and adapted for connecting the shield to a reference potential;
• whereby any abnormal condition which causes current to flow in said shield from said active probe is conducted to said reference potential to thus lessen a risk of patient injury;
• and
• monitor circuitry connected between said electrical terminal and said reference potential where the impedance between said electrical terminal and said reference potential is not more than about 20 ohms, said monitor circuitry being responsive to current in the shield to determine whether said abnormal condition exists.

An electrosurgical apparatus for use with an electrosurgical generator comprising:

• an electrically conductive, outer member having an opening extending therethrough;
• an active electrode probe having a tip and being adapted for connection to an electrosurgical generator and being mounted with respect to and extending at least partially through the outer member for effecting at the tip thereof an electrosurgical procedure;
• at least one layer of electrical insulation mounted between the active probe and the outer member;
• an electrical terminal connected to the outer member and for connecting the outer member to a reference potential;
• whereby any abnormal condition which causes current to flow in said shield from said active probe is conducted to said reference potential to thus lessen a risk of patient injury;
• and
• monitor circuitry connected between said electrical terminal and the return lead of the electrosurgical generator where the impedance between said electrical terminal and said reference potential is not more than about 20 ohms, said monitor circuitry being responsive to current in the outer member to determine whether said abnormal condition exists.