Physical mechanisms of tissue injury in electrical trauma

The author reviews data indicating that skeletal muscle cell rupture may result from either heating or electroporation due to electric shock and discusses their relative contributions to tissue injury in electrical trauma victims. It is concluded that the relative contributions of these mechanisms are probably dependent on the duration of electric current passage, the geometry of the cells, their location, and other factors. If the contact is brief, nonthermal mechanisms of cell damage may be most important. If the contact is much longer, heat damage will be most destructive. The characteristic time before heat damage predominates is probably a function of the electric field strength in the tissue. The various factors involved should also influence the pattern of injury because damage by Joule heating is not known to be dependent on cell size