Regarding high-voltage electrical burns to an extremity

The treatment of electrical injury should be modified from that of thermal burns because tissue damage is much deeper than is apparent at first inspection. The heat generated is propoional to the resistance to the flow of current. Bone, fat, and tendons offer the greatest resistance. Therefore, the tissue deep within the center of an extremity may be injured while more superficial tissues are spared. For this reason, the quantification of fluid requirements cannot be based on the percentage of body surface area involved, as in the Parkland,Brooke, or Baxter formulas, which are used to calculate fluid replacement after thermal burns. Massive fluid replacement is usually essential. A brisk urine output is desirable because of the likelihood of myonecrosis with consequent myoglobinuria and renal damage. As with deep thermal burns, debridement, skin grafting, and amputation of extremities may be required following electrical injury. However, fasciotomy is more frequently required than escharotomy with electrical injury because deep myonecrosis results in increased intracompamental pressures and compromised limb perfusion. In addition, distant fractures may result owing to vigorous muscle contraction during the accident or if subsequent falls occur. Cardiac or respiratory arrest may occur if the pathway of the current includes the hea or brain. An electrical current can also damage the pulmonary alveoli and capillaries and lead to respiratory infections, a major cause of death in these victims. Owing to the deep myonecrosis that often accompanies high-voltage injury, prophylaxis for clostridia with high-dose penicillin may be considered.