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.