Electrosurgical apparatus employing constant voltage and methods of use

Electrosurgical grasper apparatus for manipulating tissue during surgery to cause hemostasis, the apparatus comprising:

• first and second grasper members, each of the first and second grasper members having proximal ends and distal ends;
• a connecting plate disposed between the proximal ends of the first and second grasper members and to which the proximal end of each of the first and second grasper members are affixed, so that the distal ends of the first and second grasper members are selectively movable from an open to a closed position;
• first and second electrodes disposed in opposition on the distal ends of the first and second grasper members;
• a power supply that provides a constant voltage waveform to the first and second electrodes having a voltage less than 120 VRMS and a crest factor of about 1.1, to cause hemostasis without arcing or an accretion of coagulum on the first and second electrodes sufficient to interfere with the ability of the first and second electrodes to cause hemostasis;
• and
• means for connecting the power supply to the first and second electrodes.

A method of performing electrosurgery on tissue using a surgical instrument having an electrode for passing a high frequency current to the tissue to partially desiccate and cause hemostasis of the tissue, without arcing or an accretion of coagulum on the electrode sufficient to interfere with the ability of the electrode to cause hemostasis, the method comprising a series of steps comprised of:

• (a) providing a surgical instrument having an electrode;
• (b) connecting the electrode to an AC power supply;
• (c) selecting and maintaining a constant output AC voltage waveform from the power supply at the electrode, wherein the voltage waveform is independent of the load impedance and has a crest factor of about 1.1;
• (d) placing the electrode in electrical contact with the tissue so that high frequency current passes through the tissue to partially desiccate the tissue and cause hemostasis thereof by depositing a peak power in the tissue in excess of 50W, without arcing or an accretion of coagulum on the electrode sufficient to interfere with the ability of the electrode to cause hemostasis.

A method of performing electrosurgery on tissue using a surgical instrument having an electrode for passing a high frequency current to the tissue to partially desiccate and cause hemostasis of the tissue, without arcing or an accretion of coagulum on the electrode sufficient to interfere with the ability of the electrode to cause hemostasis, the method comprising a series of steps comprised of:

• (a) providing a surgical instrument having an electrode;
• (b) connecting the electrode to an AC power supply;
• (c) selecting and maintaining a constant output AC voltage waveform from the power supply at the electrode, wherein the voltage waveform is independent of the load impedance and has a crest factor substantially less than 1.4;
• (d) placing the electrode in electrical contact with the tissue so that high frequency current passes through the tissue to partially desiccate the tissue and cause hemostasis thereof by depositing a peak power in the tissue in excess of 50W, without arcing or an accretion of coagulum on the electrode sufficient to interfere with the ability of the electrode to cause hemostasis.