Electrical Injuries in Emergency Medicine 

Updated: Mar 09, 2020
Author: Tracy A Cushing, MD, MPH, FACEP, FAWM; Chief Editor: Joe Alcock, MD, MS 

Overview

Background

Electrical injuries, although relatively uncommon, are inevitably encountered by most emergency physicians. Adult electrical injuries usually occur in occupational settings, whereas children are primarily injured in the household setting. The spectrum of electrical injury is broad, ranging from minimal injury to severe multiorgan involvement to death.

Electrical injuries are shown in the images below.

Grounded sites of low-voltage injury on the feet. Grounded sites of low-voltage injury on the feet.
Electrical burns to the hand. Electrical burns to the hand.

Approximately 1000 deaths per year are due to electrical injuries in the United States, with a mortality rate of 3-5%.[1] Classifications of electrical injuries generally focus on the power source (lightning or electrical), voltage (high or low voltage), and type of current (alternating or direct), each of which is associated with certain injury patterns.

This article reviews the pathophysiology, diagnosis, and treatment of electrical injuries caused by manufactured electricity; for further information on lightning injuries, please see Lightning Injuries.

Medicolegal concerns

Litigation concerning occupational injuries is to be expected, but law suits against practitioners in such cases are rare. Detailed documentation of the presence of electrical burns, including diagrams, can be extremely helpful. Obtain photographic records of injuries, with proper consent, if possible.

Pathophysiology

Electricity is generated by the flow of electrons across a potential gradient from high to low concentration through a conductive material. The voltage (V) represents the magnitude of this potential difference and is usually determined by the electrical source. The type and extent of an electrical injury is determined by voltage, current strength, resistance to flow, the duration of contact with the source, the pathway of flow, and the type of current (ie, direct or alternating).

Voltage

Electrical injuries are typically divided into high-voltage and low-voltage injuries, using 500V or 1000V as the cutoff. High morbidity and mortality has been described in 600V direct current injury associated with railroad "third rail" contact.[2] In the United States and Canada, typical household electricity provides 110V for general use and 240V for high-powered appliances, while industrial electrical and high-tension power lines can have more than 100,000V.[3] Voltage is directly proportional to current and indirectly proportional to resistance, as expressed by Ohm's Law:

V = I X R; where I = current, V = voltage, R = resistance.

Current

The volume of electrons flowing across the potential gradient is the current, which is measured in amperes (I). It is a measure of the amount of energy that flows through a body. Energy is perceptible to the touch at a current as low as 1 mA. A narrow range exists between perceptible current and the "let go" current: the maximum current at which a person can grasp and then release the current before muscle tetany makes it impossible to let go. The "let go" current for the average child is 3-5 mA; this is well below the 15-30 A of common household circuit breakers. For adults, the "let go" current is 6-9 mA, slightly higher for men than for women. Skeletal muscle tetany occurs at 16-20 mA. Ventricular fibrillation can occur at currents of 50-100 mA.[4]

Resistance

The impedance to flow of electrons across a gradient is the resistance (R) and varies depending on the electrolyte and water content of the body tissue through which electricity is being conducted. Blood vessels, muscles, and nerves have high electrolyte and water content, and thus low resistance, and are good conductors of electricity–better than bone, fat, and skin.[5] Heavily calloused areas of skin are excellent resistors, whereas a moderate amount of water or sweat on the skin surface can decrease its resistance significantly.

Type of circuit

Electrical current can flow in 1 of 2 types of circuits: direct current (DC) or alternating current (AC), in which the flow of electrons changes direction in rhythmic fashion. AC is the most common type of electricity in homes and offices, standardized to a frequency of 60 cycles/sec (Hz).

High-voltage DC often causes a large single muscle contraction that throws the victim away from the source, resulting in a brief duration of contact with the source flow. In contrast, AC of the same voltage is considered to be approximately 3 times more dangerous than DC, because the cyclic flow of electrons causes muscle tetany that prolongs victims' exposure to the source. Muscle tetany occurs when fibers are stimulated at 40-110 Hz; the standard 60 Hz of household current is within that range. If the source contact point is the hand, when tetanic muscle contraction occurs the extremity flexors contract, causing the victim to grasp the current and resulting in prolonged contact with the source.

Table. Physiologic Effects of Different Electrical Currents (Open Table in a new window)

Effect

Current (milliamps)

Tingling sensation/perception

1-4

Let-go current – Children

3-4

Let-go current - Women

6-8

Let-go current – Men

7-9

Skeletal muscle tetany

16-20

Respiratory muscle paralysis

20-50

Ventricular fibrillation

50-120

Types of electrical burns

Depending on the voltage, current, pathway, duration of contact, and type of circuit, electrical burns can cause a variety of injuries through several different mechanisms.

A histologic picture of an electrical burn is shown below.

A histologic picture of an electrical burn showing A histologic picture of an electrical burn showing elongated pyknotic keratinocyte nuclei with vertical streaming and homogenization of the dermal collagen (40X). Courtesy of Elizabeth Satter, MD.

Direct contact

Current passing directly through the body will heat the tissue causing electrothermal burns, both to the surface of the skin as well as deeper tissues, depending on their resistance. It will typically cause damage at the source contact point and the ground contact point. Contact burns are shown in the image below.

Contact electrical burns, 120-V alternating curren 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 arcs

Current sparks are formed between objects of different electric potential that are not in direct contact with each other, most often a highly charged source and a ground. The temperature of an electrical arc can reach 2500-5000o C, resulting in deep thermal burns where it contacts the skin. These are high-voltage injuries that may cause both thermal and flame burns in addition to injury from direct current along the arc pathway.

Flame

Ignition of clothing causes direct burns from flames. Both electrothermal and arcing currents can ignite clothing.

Flash

When heat from a nearby electrical arc causes thermal burns but current does not actually enter the body, the result is a flash burn. Flash burns may cover a large surface area of the body but are usually only partial thickness.

Etiology

Electrical injury occurs when a person becomes part of an electrical circuit or is affected by the thermal effects of a nearby electrical arc. Injuries are caused by high-voltage AC, low-voltage AC, or DC.

High-voltage AC

High-voltage injuries most commonly occur from a conductive object touching an overhead high-voltage power line. In the United States, most electric power is distributed and transmitted by bare aluminum or copper conductors, which are insulated by air. If the air is breached by a conductor, (eg, an aluminum pole, antenna, sailboat mast, crane), any person touching the conductor can be injured. Occupational injuries may include direct contact with electrical switching equipment and energized components.

Low-voltage AC

Generally, 2 types of low-voltage injury occur: children biting into electrical cords producing lip, face, and tongue injuries, or the adult who becomes grounded while touching an appliance or other object that is energized. The latter type of injury is decreasing with the increasing use of ground fault circuit interrupters (GFCIs) in circuits where people might easily become grounded. GFCIs stop current flow in the event of a leakage current (ground fault) if the ground fault is greater than 0.005 amps (0.6 W at 120V).

Direct current (DC)

DC injuries are generally encountered when the third energized rail of an electrical train system is contacted while the person is grounded. This sets up a circuit of electric current through the victim, causing severe electrothermal burns and myonecrosis.[2]

Epidemiology

US frequency

Electrical injuries are estimated to cause approximately 500-1000 deaths per year in the United States.[3, 4] They are responsible for 3-5% of all burn unit admissions and cause 2-3% of emergency department burn visits in the pediatric population.

Some evidence exists that the incidence of low-voltage injuries among children is declining, perhaps because of widespread use of ground fault circuit interrupters (GFCIs), but rates of high-voltage injuries, usually involving power lines or rail sources, has remained steady.[6] Due to the nature of occupational hazards with electricity, electrical injuries represent the fourth leading cause of work-related traumatic death (5-6% of all workers' deaths).[7]

Race

No racial susceptibility to electrical burns exists. Occupational trends indicate that tradespeople in high-risk occupations are disproportionately white; therefore, this group may be more likely than other races in the United States to experience occupation-related electrical injuries.

Sex

Rates of childhood electrical injury are higher among boys than girls[6] ; rates of adult injury are significantly higher in men than in women, likely because of occupational predisposition. Most series show more than 80% of electrical injuries occur in men.[8, 9, 10, 11, 12]

Age

A bimodal distribution of electrical injuries exists among the very young (children < 6 y) and among young and working-aged adults.[13] Patterns of electrical injury vary by age (eg, low-voltage household exposures among toddlers and high-voltage exposures among risk-taking adolescents and via occupational exposure).[12, 13, 14]

Prognosis

For those without prolonged unconsciousness or cardiac arrest, the prognosis for recovery is excellent. Burns and traumatic injuries continue to cause the majority of the morbidity and mortality from electrical injuries.

Morbidity and mortality are largely affected by the particular type of electrical contact involved in each exposure. Overall mortality is estimated to be 3-15%.[1, 8] Flash burns have a better prognosis than arc or conductive burns.[5]

Persons who experience low-voltage injuries without immediate cardiac or respiratory arrest have low mortality, but there may be significant morbidity from oral trauma in children who bite electrical cords[15] or adults who suffer burns to the hand.

Persons who experience low-voltage injuries with cardiac or respiratory arrest may recover completely with immediate CPR on scene; however, prolonged CPR and transport time may result in permanent brain damage.

High-voltage injuries often produce severe burns and blunt trauma. Patients are at high risk of myoglobinuria and renal failure. Burns are often ultimately much worse than they initially appear in the ED.

Patient Education

For patient education resources, see the patient education article Thermal (Heat or Fire) Burns.

 

Presentation

History

Electrical injuries can present with a variety of problems, including cardiac or respiratory arrest, coma, blunt trauma, and severe burns of several types. It is important to establish the type of exposure (high or low voltage), duration of contact, and concurrent trauma.

Low-voltage AC injury without loss of consciousness and/or arrest

These injuries are exposures of less than 1000V and usually occur in the home or office setting. Typically, children with electrical injuries present after biting or chewing on an electrical cord and suffer oral burns. Adults working on home appliances or electrical circuits can also experience these electrical injuries. Low-voltage AC may result in significant injury if there is prolonged, tetanic muscle contraction.

Low-voltage AC injury with loss of consciousness and/or arrest

In respiratory arrest or ventricular fibrillation that is not witnessed, an electrical exposure may be difficult to diagnose. All unwitnessed arrests should include this possibility in the differential diagnosis. Query EMS personnel, family, and coworkers about this possibility. Inquire if a scream was heard before the patient’s collapse; this may be due to involuntary contraction of chest wall muscles from electrical current.

High-voltage AC injury without loss of consciousness and/or arrest

Usually high-voltage injuries do not cause loss of consciousness but instead cause devastating thermal burns. In occupational exposures, details of voltage can be obtained from the local power company.

High-voltage AC injury with loss of consciousness and/or arrest

This is an unusual presentation of high-voltage AC injuries, which do not often cause loss of consciousness. History may need to come from bystanders or EMS personnel.

Direct current (DC) injury

These injuries typically cause a single muscle contraction that throws the victim away from the source. They are rarely associated with loss of consciousness unless there is severe head trauma, and victims can often provide their own history.

Conducted electrical devices

Conducted electrical weapons (CEWs) such as tasers are weapons used by law enforcement that deliver high-voltage current that is neither true AC or DC but is most like a series of low-amplitude DC shocks.[16] They can deliver 50,000 V in a 5-second pulse, with an average current of 2.1 mA.[17] Though they have been temporally associated with deaths in the law enforcement setting, conducted electrical devices (CEDs) in healthy volunteers have been shown to be safe without evidence of delayed arrhythmia or cardiac damage as measured by troponin I.[18, 17]

One study of their use in 1201 law enforcement incidents showed mostly superficial puncture wounds from the device probes, and significant injuries only from trauma subsequent to shock, not from the device itself. Of 2 deaths in custody, neither was related to CEW exposure.[19]

Overall significant injuries from CEW exposure are rare, and usually occur due to trauma or in conjunction with intoxication.[20, 21] Of the more than 3 million CEW applications by law enforcement in the United States, only 12 published case reports suggest a link to cardiac arrest.[22] However, the issue of whether CEW usage can cause cardiac arrest is not without controversy, as some suggest a direct cardiac risk.[23]

Physical Examination

Electrical injuries can cause multiorgan dysfunction and a variety of burns and traumatic injuries. A thorough physical examination is required to assess the full extent of injuries. Occupational injuries have a high likelihood of future litigation, and physical examination findings should be documented with photographs if possible, with the proper releases, and filed in the patient's medical record.

Overall, low-voltage exposure tends to cause less overall morbidity than high-voltage, but it is important to ensure by accurate history that a seemingly low-voltage burn was not in fact from a high-voltage source (like a microwave, computer, or TV monitor—any device that "steps-up" voltage via a transformer). Low-voltage burns can still cause cardiac arrhythmias, seizures, and long-term complications if contact is near the chest or head.

Cardiovascular

Patients may present in asystole or ventricular fibrillation (VF) in addition to other arrhythmias. Sudden death due to VF is more common with low-voltage AC, whereas asystole is more often associated with high-voltage AC or DC. Ventricular fibrillation can be caused at voltages as low as 50-120 mA, which is lower than the typical household current. One series showed cardiac arrhythmias following 41% of low-voltage injuries.[11]

Electricity can also cause conduction abnormalities and direct trauma to cardiac muscle fibers. Survivors of electrical shock can experience subsequent arrhythmias, usually sinus tachycardia and premature ventricular contractions (PVCs). One study identified three cases of delayed ventricular arrhythmias up to 12 hours after the incident.[24] Other studies have shown no risk of delayed arrhythmias in patients with initially normal ECGs, both in low-voltage household exposures and after CEW exposure.[19, 20, 25, 26] One case report describes coronary artery dissection after electrical injury.[27] Long-term cardiac complications from electrical injury are rare.

Respiratory

Chest wall muscle paralysis from tetanic contraction may cause respiratory arrest if the current pathway is over the thorax. Injury to the respiratory control center of the brain can also cause respiratory arrest. The lungs are a poor conductor of electricity and generally are not as susceptible to direct injury from current as tissues with lower resistance. Case reports have described pneumothorax after electrical injury.[28]

Skin

A variety of burns and thermal injuries from electricity affect the skin and soft tissues. These are often the most severe sequelae of electrical burns after cardiac arrhythmias and may initially appear minor despite significant deep tissue injury subsequently requiring fasciotomy or amputation. Burns are often most severe at the source and ground contact points; the source is usually the hands or the head while the ground is often in the feet. The strength and duration of contact with the source largely influence the severity and extent of tissue damage. All burns should be carefully documented and, if possible, photographed.

High-voltage electrothermal burns

Typically, these show a contact point where the person touched the circuit and a ground point. These may produce significant damage to underlying tissue while largely sparing the surface of the skin. These burns may appear as painless, depressed areas with central necrosis and minimal bleeding. The presence of surface burns does not accurately predict the extent of possible internal injuries, as skin with high resistance will transmit energy to deeper tissues with lower resistance. A high-voltage burn is shown below.

High-voltage electrical burns to the chest. High-voltage electrical burns to the chest.

Arc burns

When an arc of current passes from an object of high to low resistance, it creates a high temperature pathway that causes skin lesions at the site of contact with the source and at the ground contact point (not always the feet). These areas typically have a dry parchment center and a rim of congestion around them. There will be clues to the internal pathway taken by the arc based on the location of these surface wounds. Arcs can also cause electrothermal, flash, and flame burns, so multiple burns of varying appearance may be observed. Arcs do not occur in low-voltage injuries. An arc burn is shown below.

Arcing electrical burns through the shoe around th Arcing electrical burns through the shoe around the rubber sole. High-voltage (7600 V) alternating current nominal. Note cratering.

Flash burns

Flash burns are caused by heat from a nearby electrical arc that can reach upwards of 5000o C. These can pass over the surface of the body or through, depending on the path of the arc causing the flash. They may "splash" over the surface of the body, resulting in diffuse but relatively superficial partial-thickness burns. There is no internal electrical component. A flash burn is shown below.

Superficial electrical burns to the knees (flash/f Superficial electrical burns to the knees (flash/ferning).

Flame burns

Flame burns are caused by ignition of clothing or nearby objects. These cause thermal burns similar to other flame burns.

Low-voltage burns

These behave like ordinary thermal burns and range from local erythema to full-thickness burns. These require several seconds of contact to cause skin burns, sometimes reaching current levels high enough to cause VF before causing any significant skin damage.[4] Direct contact burns may occur only if the circuit through the person was prolonged for more than a few seconds. Low-voltage burns are shown below.

Energized site of low-voltage electrical burn in a Energized site of low-voltage electrical burn in a 50-year-old electrician.
Grounded sites of a low-voltage injury in a 33-yea Grounded sites of a low-voltage injury in a 33-year-old male suicide patient.

Contact burns

Contact burns usually have a pattern from the contacted item (branding) and may appear similar to flash burns. A contact burn is shown below.

Contact electrical burn. This was the ground of a 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.

Pediatric oral burns

These are most commonly encountered in children younger than 6 years who bite or suck on a household electrical cord. A local arc of current crosses from one side of the mouth to the other. The orbicularis oris muscle may be involved, and cosmetic deformity of the lips may occur if the burn crosses the commissure. Significant edema may be noted and within 2-3 days eschar formation. Life-threatening bleeding can occur at 2-3 weeks post injury if the labial artery is exposed when the eschar falls off. Initial presentations may underestimate the extent of the ultimate injury; patients require aggressive airway management.[15] These patients should be referred for early follow-up to a burn specialist, plastic surgeon, and an oral surgeon.

Neurologic

Most acute CNS or spinal deficits resulting from electrical injuries are due to secondary blunt trauma or burns. Often, the patient has transient confusion, amnesia, and impaired recall of events if not frank loss of consciousness. Direct effects of electrical current are most severe if the respiratory control center of the brainstem is affected resulting in respiratory arrest. Current may also cause seizure or direct spinal cord injury if there is hand-to-hand flow. Spinal cord injury can also result from direct current effects or blunt trauma. Unless a patient is completely lucid with full recollection of the events, initial C-spine immobilization is indicated.

Currents cause acute muscle tetany at relatively low currents and frequencies, like those found in most households. Muscle tetany causes victims to grasp the source, prolonging contact time, and can also paralyze respiratory muscles resulting in asphyxiation.

Long-term neurologic complications include seizures, peripheral nerve damage, delayed spinal cord syndromes, subacute infarcts,[29] and psychiatric problems from depression to aggressive behavior.

Musculoskeletal

Acute injuries include fractures from blunt trauma and compartment syndrome from burns. The chest and extremities should be examined for circumferential burns. Palpate the extremity and perform distal neurologic, vascular, and motor examination to determine if there is suspicion of a compartment syndrome. If this is the case, compartment pressure can be measured and early fasciotomy may help prevent subsequent amputation.[10] If available, early surgical consultation should be obtained for a patient with concerns for compartment syndrome. Massive muscle damage can cause severe rhabdomyolysis and subsequent renal failure.

ENT/head

The head is a common point of entry for high-voltage injuries. Patients may have perforated tympanic membranes, facial burns, and cervical spine injury. Approximately 6% of victims develop cataracts, usually months after the initial injury, with increasing frequency the closer contact is to the head.[9, 30]

Complications

Low-voltage

If no significant burns are present and if consciousness returns before arriving to or in the ED, full recovery is expected. Rare persistent arrhythmias have been reported.

Persistence of unconsciousness carries a worse prognosis, and full recovery is not expected after 24 hours of unconsciousness.

With proper treatment, the disfigurement of low-voltage mouth injuries can be minimized. Scarring is almost always present.

High-voltage

Survival with massive burns is now the rule rather than the exception. However, rates of amputation and significant morbidity from traumatic injuries and burns remain high.

 

DDx

 

Workup

Laboratory Studies

In all patients with more than a trivial electrical injury and/or exposure, the following tests should be considered:

  • CBC count: Obtain values for hemoglobin, hematocrit, and white blood cell count.

  • Electrolytes: Assess sodium, potassium, chloride, carbon dioxide, blood urea nitrogen, and glucose.

  • Creatinine: There is a high risk of rhabdomyolysis/myoglobinuria in electrical injuries; mortality in one study was 59% for patients with acute renal failure.[31]

  • Urinalysis: Obtain values for specific gravity, pH, hematuria, and urine myoglobin if the urinalysis is positive for hemoglobin.

  • Serum myoglobin: If urine is positive for myoglobin, a serum level should be obtained.

  • Arterial blood gas: This is obtained for patients needing ventilatory support or those with severe rhabdomyolysis who require urine alkalinization therapy.

  • Creatine kinase (CK) levels: This level may be extremely elevated in patients with massive muscle damage from high-voltage injuries. Normal CK values published by the laboratory may be low for typical construction and electrical workers whose vocation involves heavy exercise. Some evidence suggests that initial CK levels may help predict which patients could benefit from early fasciotomy to prevent subsequent amputations.[10]  CK-MB subfractions are also often elevated in electrical injuries, but their significance in the setting of electrical injuries is not known.[3] CK-MB fractions and troponin should be checked if the current pathway involved the chest/thorax, if the patient has any signs of ischemia or arrhythmia on ECG, or if the patient has specific complaints of chest pain. One retrospective review created a decision rule for clinical identification of patients likely to have rhabdomyolysis.[32] Multivariate modeling revealed that high-voltage exposure, prehospital cardiac arrest, full-thickness burns, and compartment syndrome were associated with myoglobinuria. Defining "positive" as two or more of these findings has a sensitivity of 96% and negative predictive value of 99%. Initial CK and myoglobin levels correlate with burn size, ventilator days, hospital length of stay, need for surgical intervention, sepsis, and mortality.[33]

Imaging Studies

Choice of imaging studies is dictated by the presence of blunt trauma, altered mental status, cardiac or respiratory arrest, and type of electrical exposure. Studies to be considered are as follows:

  • Chest radiography - Any patient with cardiac or respiratory arrest, shortness of breath, chest pain, hypoxia, CPR at the scene, or fall/blunt trauma

  • Head computed tomography - Any patient with altered mental status, significant traumatic mechanism, seizure, loss of consciousness, or focal neurologic deficits

  • Cervical/spine imaging - Patients with loss of consciousness or significant trauma should be cervical spine immobilized and imaged accordingly. Clinical clearance may be appropriate for some patients with normal mental status without significant injuries. Patients with focal neurologic deficits or evidence of spinal cord injury should undergo full spinal imaging.

  • CT/ultrasonography - Depending on the amount of trauma sustained and the pathway of the current exposure, patients may require further imaging to evaluate for internal injuries. Imaging modality varies depending on suspected injury and availability.

Other Tests

ECG/cardiac monitoring

All adult patients should have an initial ECG and cardiac monitoring in the ED. The duration of monitoring depends on the circumstances of the exposure; any patients with chest pain, arrhythmia, abnormal initial ECG, cardiac arrest, loss of consciousness, transthoracic conduction, or history of cardiac disease should undergo monitoring. No definitive guideline is available on duration of monitoring for adults, but patients are unlikely to develop significant arrhythmias after 24-48 hours if they have no other significant injuries. Several large reviews have not identified risk of delayed arrhythmia among patients with low-voltage exposure and no arrhythmia upon initial presentation. One such review of 196 exposures concludes that admission for cardiac monitoring is not indicated for such patients.[34]

Several studies have shown that low-voltage (household) exposures in patients with no cardiac complaints and a normal initial ECG can be safely discharged.[35] It is unclear how this applies to patients with preexisting heart disease. In the pediatric population, healthy children with household current exposures (120 to 140V, no water contact) can be safely discharged if they are asymptomatic, without a VF or cardiac arrest in the field, and have no other injuries requiring admission.[26, 36]

Procedures

Obtain intravenous access in all adult patients with electrical injuries. Consider central access in any patient with significant trauma, large burns, cardiac or respiratory arrest, or loss of consciousness.

Fasciotomy of a burned extremity may be required in high-voltage injuries or prolonged low-voltage injuries. Obtain early surgical consultation, preferably with experience in burn management, early in the treatment of any patient with a high-voltage burn, since appropriate early fasciotomies may prevent subsequent amputations. If emergently indicated, fasciotomy should not be delayed.

 

Treatment

Prehospital Care

First, rescuers should practice awareness of scene safety and be sure there is no imminent threat to bystanders or responders in attempting to remove the victim from the electrical source. For high-voltage incidents, the source voltage should be turned off before rescue workers enter the scene.

After ensuring scene safety, rescuers should approach victims of electrical injuries as both trauma and cardiac patients. Patients may need basic or advanced cardiac life support and should undergo spinal immobilization as indicated by the mechanism of injury.

Given that injuries may be limited to a ventricular arrhythmia or respiratory muscle paralysis, aggressive and prolonged CPR should be initiated in the field for all electrical injury victims, as they are likely to be younger with fewer comorbid conditions and have better chances of survival after prolonged CPR.

Emergency Department Care

Stabilize patients and provide airway and circulatory support as indicated by ACLS/ATLS protocols. Obtain airway protection and provide oxygen for any patient with severe hypoxia, facial/oral burns, loss of consciousness/inability to protect airway, or respiratory distress. Cervical spine immobilization with or without spinal immobilization is needed based on the mechanism of injury/neurologic examination. Primary survey should assess for traumatic injuries such as pneumothorax, peritonitis, or pelvic fractures.

After primary assessment, begin fluid resuscitation and titrate to urine output of 0.5-1 mL/kg/h in any patient with significant burns or myoglobinuria. Consider furosemide or mannitol for further diuresis of myoglobin. Urine alkalinization increases the rate of myoglobin clearance and can be achieved using sodium bicarbonate titrated to a serum pH of 7.5. Obtain adequate intravenous access for fluid resuscitation, whether peripheral or central. Initiate cardiac monitoring for all patients with anything more than trivial low-voltage exposures.

Burn care should include tetanus immunization as indicated, wound care, measurement of compartment pressures as indicated, and it may include early fasciotomy. Extremities with severe burns should be splinted in a functional position after careful documentation of full neurovascular examination.

The risks of electrical injury to the fetus in a pregnant patient are unknown. Pregnant women who are involved in electrical injuries should have a careful examination for traumatic injuries and obstetrical consultation. Women in the second half of pregnancy should be admitted for fetal monitoring in any cases of severe electrical injuries, high-voltage exposures, or minor electrical injuries with significant trauma.

Further Inpatient Care and Transfer

Further inpatient care

Inpatient care is required for patients with anything other than minor low-voltage injuries. Burn and trauma care, preferably at a specialized center, should be instituted early. Any patients with cardiac arrest, loss of consciousness, abnormal ECG, hypoxia, chest pain, dysrhythmias, and significant burns or traumatic injuries must be admitted.

Transfer

All patients with a history of exposure to high-voltage electricity and patients with significant burns should be transferred to a specialized burn center for further inpatient treatment and rehabilitation.

Pediatric patients with significant oral burns should be transferred to a pediatric burn center. Patients with minor oral burns who have close follow-up can be discharged.

Consultations

Patients with high-voltage electrical injuries require the ongoing care of a burn specialist, which should be instituted as early as possible, as aggressive early intervention via fasciotomy can prevent subsequent limb amputation.

Consider additional consultations with a trauma/critical care specialist, orthopedist, plastic surgeon, and general surgeon, depending on the type and severity of traumatic injuries.

Prevention

Prevention of high-voltage electrical injuries requires ongoing public education about potential hazards, and targeted education to individuals in construction trades, those using cranes and lifts, or those exposed to the extreme danger of overhead power lines. One study found particularly high rates of electrical injuries in cable splicers, electricians, line workers, and substation operators.[37] Prevention strategies and occupational safety changes should be targeted to these high-risk occupations.

Prevention of household exposures requires public education about child protection, outlet covers, and appliance safety. Appliances that produce a shock should not be used until professionally repaired. Encourage use of GFCIs on all outlets but especially bathrooms, kitchens, and exterior outlets.

Long-Term Monitoring

Patients exposed to low-voltage electrical sources who are otherwise completely asymptomatic with a normal physical examination can often be discharged from the emergency department.

Patients with minor burns or mild symptoms can be observed for several hours and discharged if their symptoms resolve and they do not have elevated CPK/myoglobinuria. Patients should be made aware of possible long-term neurologic or ocular effects of electrical injuries, and have follow-up available as needed. Significant hand burns should be referred to a hand specialist for close follow-up.

 

Medication

Medication Summary

Hydration is key to reducing the morbidity in severe burns. If there is significant muscle damage with myoglobinuria, fluid resuscitation is first-line treatment. Osmotic diuretics and/or alkalinizing agents may be used for myoglobinuria, but the effectiveness of these medications to prevent acute kidney injury the subject of ongoing debate.[38, 39]

Fluids

Class Summary

Extravascular pooling of fluids through damaged endothelium leads to vascular hypovolemia and hypotension. Patients require fluid resuscitation with normal saline or lactated ringer.

Lactated Ringer solution

Lactated Ringer solution is essentially isotonic and has volume-restorative properties.

Osmotic diuretics

Class Summary

Osmotic diuretics assist the kidneys in excreting myoglobin if present. They can help avoid acute renal failure in patients with significant myoglobinuria.

Mannitol (Osmitrol)

Mannitol is an osmotic diuretic that is not metabolized significantly and that passes through glomerulus without being reabsorbed by the kidney.

Loop diuretics

Class Summary

These agents decrease plasma volume and edema by causing diuresis.

Furosemide (Lasix)

The proposed mechanisms for furosemide in lowering intracranial pressure include (1) lowering cerebral sodium uptake, (2) affecting water transport into astroglial cells by inhibiting cellular membrane cation-chloride pump, and (3) decreasing CSF production by inhibiting carbonic anhydrase. The dose must be individualized to patient.

 

Questions & Answers

Overview

What are electrical injuries and how do they occur?

How should occupational electrical injuries be documented?

What is the pathophysiology of electrical injuries?

What is the role of voltage in the pathogenesis of electrical injuries?

What is the role of current in the pathogenesis of electrical injuries?

What is the role of resistance in the pathogenesis of electrical injuries?

What is the role of the circuit type in the pathogenesis of electrical injuries?

What are the types of electrical burns?

What is the pathophysiology of electrical injuries from direct contact?

What is the pathophysiology of electrical injuries from electrical arcs?

What is the pathophysiology of electrical injuries from flame?

What is the pathophysiology of electrical flash burns?

How do electrical injuries occur?

How does high-voltage alternating current cause electrical injuries?

How does low-voltage alternating current cause electrical injuries?

How does direct current cause electrical injuries?

What is the prevalence of electrical injuries in the US?

What are the racial predilections of electrical injuries?

What are the sexual predilections of electrical injuries?

How does the incidence of electrical injuries vary by age?

What is the prognosis of electrical injuries?

Presentation

What are the signs and symptoms of electrical injuries?

Which clinical history findings are characteristics of low-voltage alternating current (AC) injury?

Which clinical history findings are characteristics of high-voltage alternating current (AC) injury?

Which clinical history findings are characteristics of direct current (DC) injury?

What is the role of conducted electrical devices in the pathogenesis of electrical injuries?

Which physical findings are characteristic of electrical flash burns?

Which physical findings are characteristic of electrical contact burns?

Which physical findings are characteristic of electrical injuries?

Which cardiovascular findings are characteristic of electrical injuries?

Which respiratory findings are characteristic of electrical injuries?

How are the cutaneous findings of electrical injuries characterized?

Which physical findings are characteristic of high-voltage electrothermal burns?

Which physical findings are characteristic of electrical arc burns?

Which physical findings are characteristic of electrical flame burns?

Which physical findings are characteristic of low-voltage electrical injuries?

Which physical findings are characteristic of pediatric oral electrical injuries?

Which neurologic findings are characteristic of electrical injuries?

Which musculoskeletal findings are characteristic of electrical injuries?

Which physical findings on the head are characteristic of electrical injuries?

What are the possible complications of low-voltage electrical injuries?

What are the possible complications of high-voltage electrical injuries?

DDX

What are the differential diagnoses for Electrical Injuries in Emergency Medicine?

Workup

What is the role of lab studies in the diagnosis of electrical injuries?

What is the role of imaging studies in the diagnosis of electrical injuries?

What is the role of ECG and cardiac monitoring in the evaluation of electrical injuries?

When is central venous access indicated in the management of electrical injuries?

What is the role of fasciotomy in the evaluation of electrical injuries?

Treatment

What is included in prehospital care for electrical injuries?

How are electrical injuries treated in the emergency department (ED)?

When is inpatient care indicated for the treatment of electrical injuries?

When is patient transfer indicated for the treatment of electrical injuries?

Which specialist consultations are beneficial to patients with electrical injuries?

How are electrical injuries prevented?

What is included in the long-term monitoring of electrical injuries?

Medications

Which medications are used in the treatment of electrical injuries?

Which medications in the drug class Loop diuretics are used in the treatment of Electrical Injuries in Emergency Medicine?

Which medications in the drug class Osmotic diuretics are used in the treatment of Electrical Injuries in Emergency Medicine?

Which medications in the drug class Fluids are used in the treatment of Electrical Injuries in Emergency Medicine?