1. Field of the Invention
A reflux trap for use in a plasma generator and delivery system to prevent back flow of fluids and debris from a patient to the plasma generator during a surgical procedure.
2. Description of the Prior Art
High frequency electrical energy has been widely used in surgery. Tissue is cut and bodily fluids are coagulated using electrosurgical energy.
Electrosurgical instruments generally comprise “monopolar” devices or “bipolar” devices. Monopolar devices comprise an active electrode on the electrosurgical instrument with a return electrode attached to the patient. In monopolar electrosurgery, the electrosurgical energy flows through the active electrode on the instrument through the patient's body to the return electrode. Such monopolar devices are effective in surgical procedures where cutting and coagulation of tissue are required and where stray electrical currents do not pose a substantial risk to the patient.
Bipolar devices comprise an active electrode and a return electrode on the surgical instrument. In a bipolar electrosurgical device, electrosurgical energy flows through the active electrode to the tissue of a patient through a short distance through the tissue to the return electrode. The electrosurgical effects are substantially localized to a small area of tissue that is disposed between the two electrodes on the surgical instrument. Bipolar electrosurgical devices have been found to be useful with surgical procedures where stray electrical currents may pose a hazard to the patient or where other procedural concerns require close proximity of the active and return electrodes. Surgical operations involving bipolar electrosurgery often require methods and procedures that differ substantially from the methods and procedures involving monopolar electrosurgery.
Gas plasma is an ionized gas capable of conducting electrical energy. Plasmas are used in surgical devices to conduct electrosurgical energy to a patient. The plasma conducts the energy by providing a pathway of relatively low electrical resistance. The electrosurgical energy will follow through the plasma to cut, coagulate, desiccate, or fulgurate blood or tissue of the patient. There is no physical contact required between an electrode and the tissue treate.
A disadvantage of common to plasma generators resides in the fact that during insertion of the probe into the body cavity or after a probe has already been inserted the inert gas, as well as fluids and/or debris from the patient may flow back into the plasma generator system. As a result, various components may become contaminated.
U.S. Patent application publication No. U.S. 2007/0225700 A1 relates to an apparatus for argon-plasma coagulation in which working gas is supplied to a tissue to be treated by feeding the working gas flows out the distal end of the gas-supply devices. This apparatus for argon-plasma coagulation further comprises structure to prevent contamination of the gas-supply devices by working gas, bodily gases and/or bodily liquids including at least one obstructor to obstruct a flow of gas and/or liquid into the gas-supply devices against the supply-flow direction.
U.S. Pat. No. 7,311,707 discloses a connecting device for an electrosurgical instrument comprising at least one gas supply line and one power supply line. The connecting device comprises a housing into which passes the gas supply line including the power supply line disposed therein. The connecting device include a branching device located in the housing, and by way of which the power supply line is diverted out of the gas supply line in order to form a gas-connection end piece and a power-connection end piece. A plug is fixed to the housing to form a socket in an appliance or to connecting leads running to the appliance. The gas-connection end piece and the power-connection end piece are coupled to the plug and a filter disposed within the housing in the gas-connection end piece.
U.S. Pat. No. 7,431,748 shows a separation device for the removal of impurities extracted from a flexible conduit from a fuel such as liquefied petroleum gas having a housing with an inlet and an outlet and a means for channeling the fuel from the inlet onto an impingement surface in fluid communication with the fuel stream to condense the impurities. A gravity separation means collects the impurities removed from the fuel channeled into an outlet.
Additional examples of the prior art are found in; U.S. Pat. No. 191,100: U.S. Pat. No. 540,539; U.S. Pat. No. 1,171,530; U.S. Pat. No. 3,403,497 and DE 0,056,496.
USPTO Backgrounds
USPTO Backgrounds