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ssss1 Most electrosurgery units operate within the medium radiofrequency electromagnetic spectrum. Some units operate at a higher radiofrequency (3–4 MHz) and are referred to as radio wave radiosurgery.

Source: From Huhn [3].

ssss1 Pure cut is a continuous low‐voltage waveform. Coagulation waveform is a high‐voltage intermittent waveform that allows for cooling between energy pulses. Blended waveforms provide a continuum of intermittent waveforms of varying voltages, which allow for a tissue effect more geared toward cutting or coagulation.

Source: From Huhn [3].

The monopolar system is the most commonly used electrosurgical device. It consists of a generator, an electrosurgical pencil (active electrode), and a return electrode, which is the grounding pad (passive electrode). The generator directs a current through the electrosurgical pencil, which contains the active electrode. The current then passes to the tissue through the patient's body to the grounding pad and back to the generator (ssss1). The tissue effect is determined by the power setting, waveform, technique (contact, noncontact, and time), and electrode configuration. The passive electrode should maintain a wide contact area to minimize the chance of concentrating the current and patient burning. Previous rigid metal plates were associated with increased burns because of rigidity, which often led to decreased contact with the plate to the patient. Newer electrosurgery generators also come with return electrode monitoring (REM), in which a generator will cease operation if the return signal is outside programmed limits.