How can electrosurgical sparks generate undesirable effects?

Electrosurgical sparks are responsible for the cutting, fulguration and desiccation effects in electrosurgical procedures. Although the output circuitry (that one in contact with the patient) is protected against dc current by compulsory capacitance, dc electrical energies can arise from the spark mechanism. Electrosurgical sparks are not a linear phenomena and can produce undesirable electrical and therefore physiological effects, including electrostimulation and dc burns. This paper shows some of the mechanisms involved in the production of these sparks, their peculiar characteristics, and possible damage hazards, as well as the methodology used in this study.