Which of the following is a common sequelae of electrical injury?
A. Cardiac arrhythmiasMyoglobinuria frequently accompanies electrical burns, but the clinical significance appears to be trivial. Disruption of muscle cells releases cellular debris and myoglobin into the circulation to be filtered by the kidney. If this condition is untreated, the consequence can be irreversible renal failure. However, modern burn resuscitation protocols alone appear to be sufficient treatment for myoglobinuria.
Cardiac damage, such as myocardial contusion or infarction, may be present. More likely, the conduction system may be deranged. Household current at 110 V either does no damage or induces ventricular fibrillation. If there are no electrocardiographic rhythm abnormalities present upon initial emergency department evaluation, the likelihood that they will appear later is minuscule. Even with high-voltage injuries, a normal cardiac rhythm on admission generally means that subsequent dysrhythmia is unlikely. Studies confirm that commonly measured cardiac enzymes bear little correlation to cardiac dysfunction, and elevated enzymes may be from skeletal muscle damage. Mandatory ECG monitoring and cardiac enzyme analysis in an ICU setting for 24 hours following injury is unnecessary in patients with electrical burns, even those resulting from high-voltage current, in patients who have stable cardiac rhythms on admission.
The nervous system is exquisitely sensitive to electricity. The most devastating injury with frequent brain damage occurs when current passes through the head, but spinal cord damage is possible whenever current has passed from one side of the body to the other. Schwann cells are quite susceptible, and delayed transverse myelitis can occur days or weeks after injury. Conduction initially remains normal through existing myelin, but as myelin wears out, it is not replaced and conduction ceases. Anterior spinal artery syndrome from vascular dysregulation can also precipitate spinal cord dysfunction. Damage to peripheral nerves is common and may cause permanent functional impairment. Every patient with an electrical injury must have a thorough neurologic examination as part of the initial assessment. Persistent neurologic symptoms may lead to chronic pain syndromes, and posttraumatic stress disorders are apparently more common after electrical burns than thermal burns.
Cataracts are a well-recognized sequela of high-voltage electrical burns. They occur in 5 to 7% of patients, frequently are bilateral, occur even in the absence of contact points on the head, and typically manifest within 1 to 2 years of injury. Electrically injured patients should undergo a thorough ophthalmologic examination early during their acute care.