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1 ELECTRICAL INJURY MAIN TOPIC Description Electrical injury produces variable types of adverse effects to organs and vital neurovascular structures, often without outward physical signs of injury Potential to cause burns and deep hidden damage - Coagulation of arteries proximal to the exit wound - Injury may be much more severe than at first thought - See ELECTRICAL BURNS * Delay excision and grafting until the burn area has fully declared itself Children vulnerable to full thickness orofacial burns - Pale, painless center of lesion - Extends after a few hours - Damage to facial and carotid arteries Lightning produces a massive voltage of extremely short duration - See LIGHTNING INJURY * Deep thermal injury is unusual Clinical presentation Cardiac effects - Syncope in 33% of pediatric electrical injury - Asystole most likely due to direct current or lightning injury * 2% of pediatric electrical shock - Ventricular dysrhythmia * 4% of pediatric electrical shock * Case series of 8 patients suffering cardiac arrests due electronic control device use included 3 teenagers 22 - Other dysrhythmia - Conduction defects (heart block) common, generally resolve without treatment - Cardiac contusion far more common than infarction Respiratory effects - Respiratory paralysis due to injury to medullary respiratory center - May persist longer than asystole such that a return to sinus rhythm may degenerate into ventricular fibrillation CNS effects - Altered level of consciousness: confusion, cognitive or memory defects - Seizures - Neurogenic shock - Brain stem injury with flaccid paralysis - Spinal, sympathetic, and peripheral nerve damage - Sensory and motor deficits may not match - Keraunoparalysis (transient weakness in limb) with autonomic dysfunction after lightning strike * Reversible transient paralysis

2 * Fixed and dilated pupils: not a reason to stop resuscitation Vascular effects - More common with electrical rather than lightning injury - Spasm: Maximal decrease in blood flow at 36 hours - Delayed thrombosis: due to prolonged decreased endothelial and smooth muscle function 15 - Aneurysm - Arterial rupture: high voltage 17 - Subdural, epidural, or intraventricular hemorrhage - Shock may occur due to vasomotor instability Skin - Burns are common: more frequently requiring grafting than chemical burns in children 20 - Small exit, entry wounds may mask extensive damage to blood vessels, muscles, nerves - Deep burns are uncommon with lightning - Oral burns occur in children chewing on cords, potentially leading to delayed labial artery bleeding Musculoskeletal - Rhabdomyolysis and myoglobinuria can produce renal failure - Fractures or dislocations due to muscle spasm are rare Eye effects - Cataracts, corneal lesions, intraocular hemorrhages, retinal detachment, optic nerve injury Ear effects 18 - Tympanic membrane perforation: lightning - Transient vertigo: electrical - Sensorineural hearing loss: electrical Gastrointestinal effects - Rare - Ulcers or evisceration, stomach and intestinal perforation, esophageal stricture - Electrocoagulation of liver and spleen Blunt trauma common from secondary fall after injury Deleted:, Deleted: d Deleted:, Deleted: a Deleted: Maximal decrease in blood flow at 36 hours BASIC SCIENCE Factors that determine the severity of electrical injury Voltage - Measurement of the "electrical pressure" in a system - High voltage * > 1000 volts * Usually more damaging than low voltage with tendency to "throw" victim (which may help limit contact) * High voltage takes a direct course to ground

3 * Electronic control devices (i.e. TASER) fall in this category - Low voltage * < 1000 volts * Follows path of least resistance Current (amperage) - Current more critical than voltage - Measure of the rate of flow of electrons - As little as 1 milliamp may produce ventricular fibrillation - 1 milliamp perceived as a tingling sensation - AC (alternating current) * Induces tetanic muscle spasm which can prolong contact by interfering with voluntary release * Most common cause of electrocution * Frequency of the AC may precipitate ventricular fibrillation * More dangerous than direct current (DC) - DC (direct current) * Used for defibrillation etc. Duration of the contact Pathway taken by the current Resistance - Measurement of the difficulty of electron flow - Increases from nerve, blood, muscle, skin, tendon, fat, and bone - Dry skin = 40,000 ohms versus wet skin < 1000 ohms - Thin infant skin and oral mucosa = low resistance See TYPES OF ELECTRICAL INJURY EPIDEMIOLOGY Approximately 1500 deaths per year Four times more nonfatal injuries Bimodal pediatric distribution - Exploring toddlers (12 to 24 months) most commonly exposed at home, chewing on extension cords - Adolescents climbing utility poles or trespassing into transformer substations DIAGNOSTIC STUDIES Case-by-case based on severity of injuries CBC CPK Cardiac markers Electrolytes including calcium, BUN, creatinine, glucose ECG Urinalysis for myoglobin Imaging

4 - Chest x-ray if current may have passed through thorax - Cervical spine if AMS - Relevant long bones for specific injury after high voltage or lightning strike - Head CT may be indicated for head injury with loss of consciousness DIFFERENTIAL DIAGNOSIS See CAUSES OF ALOC - Hypoglycemia - Intoxication - Drug overdose - Cardiovascular disease - CVA TREATMENT Ensure safety of first responders Separate victim from source of current Reverse triage if multiple victims especially with lightning strike - Focus on those appearing dead first due to high survival Advanced life support and trauma protocols CPR if necessary - Prolonged efforts may be indicated at discretion of treating physician as most victims are young and good outcomes reported even with asystole - See BASIC CPR - See RESUS: ASYSTOLE Oxygenation and ventilation Treat dysrhythmia - ECG and enzymes poor predictors of cardiac injury - See RESUS: VENTRICULAR FIBRILLATION - See DYSRHYTHMIAS Treat seizure - See RESUS: STATUS EPILEPTICUS Maintain circulation - Fasciotomy or amputation if necessary Assess for multiple trauma Volume expansion for thermal burns - Titrate to urine output - May require more fluid that predicted by burn formulas Fluid restriction if CNS injury - Watch for and treat cerebral edema Maintain urine output to treat myoglobinuria if present - Lasix or mannitol - Alkalinize the urine - See RHABDOMYOLYSIS AND MYOGLOBINURIA

5 Comprehensive physical examination - Pay particular attention to the head and neck - Careful exam of the skin and pulses - Cranial, cerebellar, and peripheral nerve exam Clean and dress burns - Early referral to plastic surgeons but delay excision and grafting until the area declares itself - See BURNS Address obvious injuries Tetanus prophylaxis and antibiotics High voltage or lightning strike - Admit for observation and cardiac monitoring - Repeat examination over days COMPLICATIONS Considerable muscle damage may produce myoglobinuria Long term sequela from electrical and lightning injuries include - Paralysis - Dysesthesia - Peripheral mono- or polyneuropathies - Disturbances in mood, affect, and memory * up to 78% develop Diagnostic and Statistical Manual of Mental Disorders psychiatric diagnoses 19 DISPOSITION All children with oral injuries require plastic surgery or dental consults Neurosurgical, ophthalmological, and ENT consultations may be needed Transfer to a burn center may be needed Admission not required for any nontransthoracic low voltage injuries in an asymptomatic child without ECG abnormalities 16 Admit all high voltage injuries for 12 to 24 hours Admit all lightning injuries except those with a normal exam, normal lab tests, normal ECG plus adequate home supervision and close follow up care Admit those presenting with syncope for cardiac monitoring Deleted: lightning Deleted: s EDUCATION/PREVENTION Regulations requiring safety switches on power and lighting circuits Keep extension cords in good repair Cover unused outlets with dummy plugs Keep electrical appliances away from sinks and bathtubs Supervise electrically operated toys TIPS Amount of skin injury is not a reliable predictor of overall severity of injury

6 Beware of other injuries particularly fractures caused by immense muscle spasm All victims of electrical burns must be evaluated LIGHTNING INJURY Description Lightning produces a massive voltage of extremely short duration - Deep thermal injury is unusual Clinical presentation Usually obvious clinical presentation due to patient or witnesses reporting a lightning strike - See ELECTRICAL BURNS Consider lightning strike in unwitnessed falls, cardiac arrests, or unexplained coma in the outdoor setting Feathering (Lichtenberg figures) - Pathognomonic of lightning injury - Cutaneous imprints form electron showers that track over the skin - Resolve within 24 hours Types of lightning injuries Direct strike - Most serious form of injury and occurs when carrying or wearing metal objects Contact injury when lightning strikes object victim is touching Side flash or splash when victim near an object that is struck Ground current - Lightning strikes ground close to victim, travels through body from one foot to the other Thermal flash - Short duration burns Blast injury: assess for concomitant shrapnel injuries 21 - Shock wave from lightning channel can cause tympanic membrane perforation or blunt trauma from the victim being thrown Upward streamer - Weak streamer that does not become completed lightning channel Complications High incidence of death or morbidity - 30 percent mortality - 75 percent of survivors have permanent sequela - See TYPES OF ELECTRICAL INJURY TYPES OF ELECTRICAL INJURY

7 TYPE Lightning High Voltage Low voltage DURATION 1/1000 sec Brief Prolonged ENERGY 100,000,000 volts > 1,000 volts < 1,000 volts TYPE DC DC or AC Mostly AC SHOCK WAVE Present Absent Absent CARDIAC Asystole V Fibrillation Atrial or Ventricular Fibrillation 14 BURNS Superficial & minor Deep & severe Superficial RHABDOMYOLYSIS Rare Very common Common FASCIOTOMY Rare Extensive Rare MORTALITY Very high Moderate Low REFERENCES Topic supported by DynaMed Systematic Literature Surveillance

8 Cooper M, Andrew C. Lightning Injuries. In: Auerbach P, ed. Wilderness Medicine: Management of Wilderness and Environmental Emergencies 3rd Ed. 1995: Fish RM. Electric injury, part III: cardiac monitoring indications, the pregnant patient, and lightning. J Emerg Med Feb;18(2):181-7 Glatstein MM, Ayalon I, Miller E, et al. Pediatric Electrical Burn Injuries: Experience of a Large Tertiary Care Hospital and a Review of Electrical Injury. Peds Emerg Care. 2013:29: Haim A, Zucker N, Levitas A et al. Cardiac manifestations following electrocution in children. Cardiol Young. 2008; 18(5); Koumbourlis A. Electrical Injuries. Crit Care Med Nov;30(11 Suppl):S Martinez J, Nguyen T. Electrical injuries. South Med J Dec;93(12): Nield L, Kamat D.Related Articles, Links Long-term Sequelae of Lightning Strike in a Child: A Case Report and Review. Clin Pediatr (Phila) Jul- Aug;43(6):563-7 Nguyen BH, MacKay M, Bailey B, et al. Epidemiology of electrical and lightning related deaths and injuries among Canadian children and youth. Inj Prev. 2004;10: Ritenour AE, Morton MJ, McManus JG et al. Lightning injury: a review. Burns Aug;34(5): Schaider J, Hayden S, Wolfe R, et al. eds: Electrical Injury. In: Rosen and Barkins 5 Minute Emergency Medicine Consult 2003: Schaider J, Hayden S, Wolfe R, et al. eds: Lightning Injury. In: Rosen and Barkins 5 Minute Emergency Medicine Consult 2003: Strange G, Ahrens W, Lelyveld S, Schafermeyer R, eds: Electrical and Lightning Injuries. In Pediatric Emergency Medicine: A Comprehensive Study Guide 1996: Whitcomb D, Martinez J, Daberkow D. Lightning Injuries. South Med J Nov;95(1 1): Zanoni S, Siefert J, Darracq M. Atrial Fibrillation with Rapid Ventricular Response Resulting from Low Voltage Electrical Injury. J Emerg Med May;45(5):e149-e Park K, Park W, Kim M, Kim H, Kim S, Cho G, Choi Y. Alterations in Arterial Function after High-voltage Electrical Injury. Critical Care 2012 Feb;16:R Searle J, Slagman A, Maab W, Mockel M. Cardiac Monitoring in Patient with Electrical Injuries. Dtsch Arzebl Int 2013 June;110(50): Toy J, Ball B, Tredget E. Carotid Rupture Following Electrical Injury: a Report of 2 Cases. J Burn Care Res. 2012;33:e161-e Modayil P, Lloyd G, Mallik A, Bowdler D. Inner Ear Damage Following Electrical Current and Lightning Injury: a Literature Review. Eur Arch Otorhinolaryngol. 2014;271:

9 19. Wesner M, Hickie J. Long-term Sequelae of Electrical Injury. Can Fam Physician Sept;59: Alemayehu H, Tarkowski A, Dehmer J, Kays D, St. Peter S, Islam S. Management of Electrical and Chemical Burns in Children. J Surg Res Jul;190(1): van Waes O, van de Woestinje P, Halm J. Thunderstruck : Penetrating Thoracic Injury from Lightning Strike. Ann Emerg Med Apr;63(4): Zipes D. Sudden Cardiac Arrest and Death Following Application of Shocks from TASER Electronic Control Device. Circulation. 2012;125: SEE ALSO See CENTRAL VASCULAR ACCESS See ELECTRICAL BURNS See HAND INJURIES See PERIPHERAL VASCULAR ACCESS See RESUS: ASYSTOLE See RESUSCITATION DRUGS See RHABDOMYOLYSIS EBSCO Health All rights reserved worldwide.