Introduction and Basics of Electrosurgery - Electrosurgery is the application of high-frequency electrical current to biological tissue. - It can be used to cut, coagulate, desiccate, or fulgurate tissue. - Precise cuts with limited blood loss can be achieved. - Electrosurgical devices are commonly used in surgical operations to prevent blood loss. - It differs from electrocautery, which uses heat conduction from a heated probe.

Electrosurgical Techniques and Types - Tissue is heated by an electric current in electrosurgery. - When the intracellular temperature reaches 60 degrees C, cell death occurs. - Tissue desiccation and protein coagulation occur at temperatures of 60-99 degrees C. - Rapidly reaching 100 degrees C leads to explosive vaporization of intracellular contents. - Electrosurgical forceps can be used for desiccation, coagulation, vaporization, and cutting. - Electrosurgery includes processes of electrocoagulation, vaporization, and fulguration. - Electrocautery is sometimes incorrectly used to describe electrosurgery. - Fulguration is a superficial type of coagulation achieved by arcing modulated high voltage current. - Vaporization can be used to ablate tissue targets or cut tissue by linear extension. - Different voltage waveforms and frequencies are used for different electrosurgical processes.

Diathermy, RF Electrosurgery, and Electrical Stimulation - Diathermy refers to dielectric heating produced by molecular dipoles in a high-frequency electromagnetic field. - RF electrosurgery is commonly used in various surgical disciplines. - It is performed using an electrosurgical generator and a handpiece with one or two electrodes. - Monopolar instruments require the use of a dispersive electrode to prevent thermal injury to underlying tissue. - Bipolar instruments involve two active electrodes or one active electrode and one dispersive electrode. - Neural and muscle cells can be stimulated by electric current. - Stimulation threshold decreases with increasing frequency in the kHz range and above. - Electrosurgical equipment typically operates in the RF range of 100kHz to 5MHz. - Higher frequencies help minimize the generation of hydrogen and oxygen during electrolysis. - Minimizing gas bubble generation is important for procedures in closed compartments.

Electrosurgical Instruments and Modalities - Dispersive electrode: attached to RF generator or electrosurgical unit - Active electrode: pointed or blade-shaped electrode used to make contact with tissue - Tissue effects: vaporization, electrosurgical cutting, desiccation and protein coagulation - Current density: decreases rapidly with distance from active electrode - Heating occurs in a localised region near the electrode - Bipolar instruments: both electrodes on the same design, dispersive electrode is larger than the active electrode - Dedicated non-grounded machines: low-powered high frequency electrosurgery, can be performed on conscious outpatients - Electrosurgical modalities: cutting mode, coagulation mode, desiccation mode, fulguration mode - Wet field electrosurgery: operates in saline solution or open wound, smallest or sharpest electrode generates most heat

Safety Considerations and Advancements in Electrosurgery - Electrosurgery involves the use of electrical energy to cut, coagulate, or ablate tissue. - The heating effect is achieved by passing an electrical current through tissue. - The proportion of ON time to OFF time can be varied to control the heating rate. - Pulse-width modulation is used to achieve an average amplitude of the electrical current. - Modern electrosurgical generators provide sophisticated waveforms with real-time power adjustment. - To prevent burns, a good electrical contact between the body and the return electrode is necessary. - Surgical smoke produced by electrosurgery contains volatile organic compounds (VOCs). - Precautions should be taken to prevent ignition of flammable materials in the operating room. - William T. Bovie is credited with developing the first commercial electrosurgical device. - Advancements in electrosurgical technology have led to the development of advanced energy devices.