Abstract: A surgical instrument is described that incorporates bipolar electrodes on opposing shearing members for passing a high frequency current through the tissue for causing hemostasis of the tissue and for cutting the tissue. An electrically insulating material is interposed between the shearing members so that the electrodes are spaced apart from 0.002 to 0.050 inches and the current passes between the opposing electrodes through the tissue and not between the opposing shearing surfaces. The insulating material has a higher hardness than the opposing members to reduce wear of the insulation and provide a self-sharpening feature. Methods of simultaneously causing tissue and severing tissue are also provided. The use of a constant voltage high frequency power supply to deliver current to the tissue to cause hemostasis is described in conjunction with those methods.

Abstract: A surgical instrument is described that incorporates bipolar electrodes on opposing shearing members for passing a high frequency current through the tissue for causing hemostasis of the tissue and for cutting the tissue. An electrically insulating material is interposed between the shearing members so that the electrodes are spaced apart from 0.002 to 0.050 inches and the current passes between the opposing electrodes through the tissue and not between the opposing shearing surfaces. The insulating material has a higher hardness than the opposing members to reduce wear of the insulation and provide a self-sharpening feature. Methods of simultaneously causing tissue and severing tissue are also provided. The use of a constant voltage high frequency power supply to deliver current to the tissue to cause hemostasis is described in conjunction with those methods.

Abstract: Endoscopic surgical instruments are provided that have bipolar electrodes on opposing movable members for passing a high frequency current through tissue for simulataneously severing or manipulating the tissue and causing hemostasis of the tissue. An electrically insulating material is interposed between the movable members so that the electrodes are spaced apart from 0.002 to 0.050 inches and the current passes between the opposing electrodes through the tissue. Methods of endoscopically achieving hemostasis while simultaneously, manipulating and cutting tissue are also provided. Use of a constant voltage high frequency power supply to deliver current to the tissue to cause hemostasis is described in conjunction with those methods.

Abstract: Endoscopic surgical instruments are provided that have bipolar electrodes on opposing movable members for passing a high frequency current through tissue for simulataneously severing or manipulating the tissue and causing hemostasis of the tissue. An electrically insulating material is interposed between the movable members so that the electrodes are spaced apart from 0.002 to 0.050 inches and the current passes between the opposing electrodes through the tissue. Methods of endoscopically achieving hemostasis while simultaneously, manipulating and cutting tissue are also provided. Use of a constant voltage high frequency power supply to deliver current to the tissue to cause hemostasis is described in conjunction with those methods.

Abstract: An adaptor cable and methods are provided for use with electrosurgical bipolar instruments and standard commercially available electrosurgical generators that reduce arcing. The adaptor cable limits the peak-to-peak voltage developed between the electrodes of the electrosurgical instrument by providing a minimum load impedance between the output terminals of the electrosurgical generator.

Abstract: Adaptors are provided for use with electrosurgical bipolar instruments and standard commercially available electrosurgical generators that reduce coagulum buildup and sticking on electrosurgical instruments. A first type of adaptor converts a high voltage, high crest factor output voltage waveform typical of conventional electrosurgical generators to a more desirable lower voltage, lower crest factor regime. A second type of adaptor limits the peak open-circuit voltage supplied by a conventional electrosurgical generator to an electrosurgical instrument.

Abstract: An instrument for use in endoscopic surgery is provided. The instrument has a heating element with a working surface for providing hemostasis at an auto-regulated temperature. The working surface may include a tapered edge for providing thermally-enhanced cutting and a non-stick coating for operating the instrument at low auto-regulation temperatures. A process for making the instrument is also provided. Additionally, a method of performing endoscopic surgery on a patient's internal tissue is also provided.

Abstract: An irrigation arrangement is provided for electrically powered endoscopic probes that supplies the surgeon with suction or irrigation on demand. The irrigation arrangement is described for use with endoscopic probes employing thermal auto-regulating and bipolar electrosurgical probe tip configurations. An extendable shroud is also provided for selectively covering tip of the endoscopic probe while positioning or manipulating the endoscopic probe at the surgical site.

Abstract: Bipolar surgical instruments for simultaneously cutting and coagulating tissue are provided that feature increased manufacturability and durability, reduced component cost and reduced assembly requirements. The bipolar instruments include opposite polarity electrodes isolated by a layer of electrical insulation deposited and specially prepared to reduce electrical breakdown and increase smoothness. A pivot pin connecting the electrodes is impregnated with hydrophobic material, and organic materials are generally avoided in the components and manufacture of the instruments. A simplified design for an endoscopic bipolar instrument is also provided to reduce cost and improve manufacturability and durability of such devices.

Abstract: An instrument for use in surgery is provided. The instrument has a heating element with a working surface for providing hemostasis at an auto-regulated temperature. The working surface may include a tapered edge for providing thermally-enhanced cutting and a non-stick coating for operating the instrument at low auto-regulation temperatures. A process for making the instrument is also provided. Additionally, a method of performing surgery on a patient's tissue is also provided.

Abstract: An instrument for use in endoscopic surgery is provided. The instrument has a reusable shaft to which a disposable working tip can be removably attached. The disposable working tip has a working surface for providing hemostasis at an auto-regulated temperature. The working surface may include a tapered edge for providing thermally-enhanced cutting and a non-stick coating for operating the instrument at low auto-regulation temperatures. The instrument is capable of being used for a wide variety of endoscopic surgical procedures.

Abstract: Methods and apparatus are provided for use in performing electrosurgery, wherein a power supply supplies an electrosurgical instrument with a low voltage power signal having a substantially constant peak-to-peak voltage that is independent of the load impedance and which has a crest factor near unity. A power supply is provided to supply a voltage waveform in accordance with the methods of the invention. A clipping circuit is also provided to permit practice of the methods using conventional electrosurgcial generators and previously known electrosurgical instruments, wherein the voltage amplitude and waveform is modified to the desired regime.

Abstract: A power supply for use with resistively-heated surgical instruments is provided, wherein the desired operating conditions of the surgical instrument are determined by a set-point determination circuit in combination with a set-point indicator element. The power supply includes an impedance matching circuit and current step-up transformer for reducing power loss in the cable connecting the surgical instrument to the power supply. A method of regulating the output of a power supply used with resistively-heated surgical instruments is also provided.

Abstract: Endoscopic surgical instruments are provided that have detachable working ends for use with a reusable handle portion. The detachable working end includes bipolar electrodes on opposing movable members for passing a high frequency current through tissue for simultaneously severing or manipulating the tissue and causing hemostasis of the tissue. An electrically insulating material is interposed between the movable members so that the electrodes are spaced apart from 0.002 to 0.050 inches and the current passes between the opposing electrodes through the tissue.

Abstract: A power supply for use with resistively-heated surgical instruments is provided, wherein accurate temperature regulation is achieved employing a resistance feedback circuit. The power supply powers the surgical instrument with an AC voltage waveform, and applies a fixed, low level DC signal to the heating element to produce a DC signal proportional to the instantaneous resistance of the heating element. The DC signal is compared to a setpoint value to obtain a control signal for adjusting the power delivered to the instrument to maintain a substantially constant heating element temperature, even under varying thermal loads.

Abstract: Endoscopic surgical instruments are provided that have bipolar electrodes on opposing movable members for passing a high frequency current through tissue for simulataneously severing or manipulating the tissue and causing hemostasis of the tissue. An electrically insulating material is interposed between the movable members so that the electrodes are spaced apart from 0.002 to 0.050 inches and the current passes between the opposing electrodes through the tissue. Methods of endoscopically achieving hemostasis while simultaneously, manipulating and cutting tissue are also provided. Use of a constant voltage high frequency power supply to deliver current to the tissue to cause hemostasis is described in conjunction with those methods.

Abstract: A surgical instrument is described that incorporates bipolar electrodes on opposing shearing members for passing a high frequency current through the tissue for causing hemostasis of the tissue and for cutting the tissue. An electrically insulating material is interposed between the shearing members so that the electrodes are spaced apart from 0.002 to 0.050 inches and the current passes between the opposing electrodes through the tissue and not between the opposing shearing surfaces. The insulating material has a higher hardness than the opposing members to reduce wear of the insulation and provide a self-sharpening feature. Methods of simultaneously causing tissue and severing tissue are also provided. The use of a constant voltage high frequency power supply to deliver current to the tissue to cause hemostasis is described in conjunction with those methods.

Abstract: A bipolar snare instrument for use in surgery is provided. The snare instrument has a snaring loop comprising a flexible continuous electrically-insulating loop for supporting bipolar electrodes. The electrodes may be arranged in various geometries on the insulating loop to provide localized selective necrosis and hemostasis of a patient's protruding tissue. Methods of performing surgery with such devices are also provided.