Medical Therapy
Patients with electrical injury should be initially evaluated as a trauma patient. [22, 23] Airway, breathing, circulation, and inline immobilization of the spine should be performed as a part of primary survey. Maintain a high index of suspicion and evaluate for hidden injuries. Intravenous access, cardiac monitoring, and measurement of oxygen saturation should be started during the primary survey. Fluid replacement is the most important aspect of the initial resuscitation. [24] As with conventional thermal injury, electrical injuries cause massive fluid shifts with extensive tissue damage and acidosis; therefore, monitoring a patient's hemodynamics is important. A Foley catheter is helpful in monitoring urine output and, therefore, tissue perfusion.
Initial fluid resuscitation should aim for urine output of greater than 0.5 cc/kg/h if no signs of myoglobinuria are present and preferably greater than 1 cc/kg/h if myoglobinuria is present. Since lightning burns are usually superficial, using a standard formula, such as the Parkland formula, may be helpful.
The extent or volume of tissue damage involved with an electrical injury is difficult to assess. The unpredictable nature of electrical injuries makes estimating fluid deficits much more difficult. Many authors increase fluid replacement after an electrical injury.
Based on the Parkland formula, increase fluid replacement by 2-3 times, depending on the total surface area potentially involved. For example, increase it by 3 if the surface area is 20% and increase it by 2 (or less) according to an increased percentage of burned skin. These formulas estimate necessary initial resuscitation volume over the first 24 hours (started at the time of the burn).
Use an isotonic balanced saline solution (eg, Ringer's lactate solution) for fluid resuscitation. Closely follow urinary output as an indicator of hemodynamic status and kidney function. Make constant adjustments based on hourly urine output. Decrease or increase fluid rates to maintain urine output of 0.5-1 cc/kg/h.
Installing an indwelling urinary catheter is mandatory. Hematuria or dark urine prompts the need for more aggressive therapy to prevent myoglobin-induced tubular necrosis. This is treated with fluids (initiating diuresis) and bicarbonate.
Administer bicarbonate at 1-2 mEq/kg. With very extensive injuries, expect acidosis and myoglobinuria, and initiate bicarbonate with the initial fluid bolus.
Administer mannitol at 1 gram per kilogram body weight to promote an osmotic diuresis. The target urine output is up to 2-3 mL/kg/h, with a urine pH greater than 6.5. Bicarbonate treats the underlying acidosis and alkalinizes the urine, making myoglobin more soluble.
Additional diuretics may be administered. Acetazolamide is the recognized drug of choice because it also alkalinizes the urine. However, exercise this diuresis with extreme caution to avoid hyperosmotic hypoalbuminemia.
Surgical Therapy
Functional outcome of an electrical burn wound is inversely proportional to the time lapsed before the start of the reconstructive procedure(s). [22, 23]
As part of the nature of the electrical trauma, tissue damage leads to vascular thrombosis and skin and muscle necrosis. This leads to gross limitation on manipulation of local tissues for reconstruction. The optimal management of these wounds has evolved to initial debridement, decompression (fasciotomy), and aggressive planned debridement and early skin coverage with the goal of preserving vital structures. [22, 23]
Fasciotomy serves a dual role as both a therapeutic tool and a diagnostic tool in the treatment of electrical injuries. The fact that a burn with a relatively small surface area may hide massive tissue destruction beneath cannot be overemphasized. Therefore, aggressively evaluate any swelling or signs of impaired circulation.
Impaired circulation to extremities after thermal skin injury may be the result of constrictive eschar, which usually is circumferential and of full thickness. Impaired circulation also may be the result of compartment syndrome, which is caused by edematous muscles.
Volume is limited as a result of the naturally needed fascial compartments. When edema occurs in the same volume compartment, pressures within that compartment rise. Sufficient pressure to occlude venous obstruction easily leads to muscle ischemia, increased edema, and further myonecrosis.
Compartment pressures need not exceed arterial pressures to cause necrosis. Any questionable extremity must be examined in the operating room by removing solid eschar initially, followed by fasciotomy as indicated. A low threshold for fasciotomy is indicated because an early fasciotomy may prevent ischemia and prevent (or at least limit) amputation.
Fasciotomy also serves a diagnostic role. It can be very important in helping determine the extent of muscular necrosis. Frankly debride the necrotic tissue to explore the affected limbs. Repeat assessment, either during the operation or at dressing changes, can help prevent secondary infection. Assess muscle viability with serial technetium scans. If, at second look, additional necrotic tissue is present, further debride the affected extremity. In severe cases, early amputation remains the only safe choice.
Locoregional flaps have served as good alternatives for coverage of electric burn wounds. Alternatives include myocutaneous, fasciocutaneous, and muscle flaps, with a split thickness skin graft serving as an intermediate biological cover or as a definitive procedure.
Operative Details and Follow-up
Preoperative details
Bring patients to the operating room after aggressive resuscitation has reversed shock, assured oxygen delivery, restored circulating volume, and reestablished end-organ perfusion. The patient may need tetanus prophylaxis. Bedside fasciotomy can be performed if the patient is too unstable to go to the operating room.
Intraoperative details
Follow the principles of good surgical technique. Perform fasciotomies following prescribed techniques, and ensure that any at-risk compartment is released. Make every effort to protect marginal tissue.
Postoperative details
Continue aggressive postoperative assessment for myoglobinuria. Local wound care is the surgeon's choice; the authors prefer wet-to-dry gauze dressings changed at twice-daily whirlpool sessions. Consider delayed closure of the fasciotomy site or secondary coverage when appropriate.
Follow-up
Discharge patients with open wounds if adequate wound-care arrangements are available. Follow-up care depends on the nature and extent of the injury. Secondary coverage may be needed, and consulting a plastic or reconstructive surgeon may be helpful.
For patient education resources, see the Environmental Exposures and Injuries Center and Burns Center, as well as Lightning Strike and Electric Shock.
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Arcing electrical burns through the shoe around the rubber sole. High-voltage (7600 V) alternating current nominal. Note cratering.
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Contact electrical burn. This was the ground of a 120-V alternating current nominal circuit. Note vesicle with surrounding erythema. Note thermal and contact electrical burns cannot be distinguished easily.
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Contact electrical burns, 120-V alternating current nominal. The right knee was the energized side, and the left was ground. These are contact burns and are difficult to distinguish from thermal burns. Note entrance and exit are not viable concepts in alternating current.
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Electrical burns to the hand.