Practice Essentials
Electrical injuries have become a more common form of trauma with a unique pathophysiology and with high morbidity and mortality. They encompass several types, as follows: lightning injury,
high-voltage injury, and low-voltage injury.
Clinical manifestations range from transient unpleasant sensations without apparent injury to massive tissue damage.
Some electrocutions are instantly fatal. Familiarity with the mechanisms of injury and the principles of therapy improves patient care.
Four classes of electrical injuries are as follows
:
True electrical injuries – The person becomes part of the electrical circuit and has an entrance and exit site
Flash injuries – Superficial burns caused by arcs that burn the skin; no electrical energy travels through the skin
Flame injuries – Caused by ignition of the persons clothing by arc; electricity may or may not travel through the person’s body
Lightning injuries – A unique type of injury that occurs at extremely high voltages for the shortest duration; the majority of electrical flow occurs over the body
See the images below.
Arcing electrical burns through the shoe around the rubber sole. High-voltage (7600 V) alternating current nominal. Note cratering.
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.
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.
Electrical burns to the hand.
Signs and symptoms of electrical injuries
Clinical presentations range from a tingling sensation to a widespread tissue damage and even to instantaneous death. The main symptom of an electrical injury is often a skin burn. Cardiac arrhythmias can also occur. The following are the most common electrocardiographic abnormalities:
Sinus tachycardia
Nonspecific ST- and T-wave changes
Heart blocks
Prolongation of the QT interval
See Presentation for more detail.
Diagnosis
Laboratory studies
Indicated laboratory studies include the following:
Complete blood cell count
Serum electrolyte levels
Liver function tests
Blood urea nitrogen and creatinine levels
Creatine kinase measurement
Urinalysis
Imaging studies
Radiographs of the cervical spine, chest, and pelvis should be ordered if the patient was previously unconscious. In addition, appropriate extremity radiographs should be obtained in patients with obvious extremity injuries
Other tests
An electrocardiogram should be obtained in all patients. If smoke inhalation is suspected, arterial blood gas analysis and pulse oximetry may be indicated.
See Workup for more detail.
Management
Patients with electrical injury should be initially evaluated as a trauma patient. Airway, breathing, circulation, and inline immobilization of the spine should be performed as a part of the 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.
See Treatment for more detail.