ENVIRONMENTAL EMERGENCIESELECTRICAL AND LIGHTNING INJURIESCritical Care Clinics - Volume 15, Issue 2 (April 1999)

Subin Jain MDVenkata Bandi MD

Address reprint requests toVenkata Bandi, MDDepartment of Pulmonary and Critical Care MedicineBen Taub General Hospital1504 Taub LoopHouston, TX 77030Department of Pulmonary and Critical Care Medicine, Ben Taub General Hospital, Baylor College of Medicine, Houston, Texas

Electricity and lightning account for a large number of deaths per year worldwide. According to data from the Centers for Disease Control and Prevention (CDC), 100 out of more than 500 fatalities caused by electricity are due to lightning and at least two to three times as many nonfatal injuries are reported every year in the United States. Lightning is the third most common cause of deaths from natural causes. The pathophysiology and management of electrical and lightning injuries are unique. Physicians who may encounter such patients in their practice should be knowledgeable in their management. This article reviews the current knowledge about this topic and details a schema for management.

EPIDEMIOLOGY

Deaths caused by electricity are almost always accidental and largely preventable. Work-related accidents and children account for most cases. In children, a bimodal distribution is seen, with low-voltage injuries in children less than 6 years of age and high-voltage injury in older children and adolescents. [9] [14] [15] The majority of high-voltage accidents in adults are occupationally related and occur mostly in construction and electrical workers. [16] [91] [102] It is estimated that 3% to 4% of all admissions to burn units are from burns caused by electrical injuries. [31] [41] Lightning-related casualties are commonest in May through September when thunderstorm activity is the highest. Victims are predominantly males of age 15 to 44 engaged in outdoor recreational activities. [67] [101] From 1980 through 1995, Florida and Texas had the greatest number of deaths attributable to lightning but New Mexico, Arizona, Arkansas, and Mississippi had the highest rate per million population per year. [71] It is generally believed that casualties caused by lightning are underestimated. A study by Lopez et al

[66] showed that Storm Data, a monthly publication of the National Oceanic and Atmospheric320Administration (NOAA), underestimated lightning deaths by 28% and lightning injuries requiring hospitalization by 42%.

PATHOPHYSIOLOGY

Electricity causes injury by several different mechanisms: (1) direct effect of electric current on body tissues, (2) conversion of electrical energy to thermal energy and subsequent superficial and deep burns, (3) blunt injury caused by severe muscle contractions or fall. [16] [31] [47] [91] The primary determinant of electrical injury is the amount of current flowing through body tissues. [36] [86] Kouwenhoven [61] described six variables that affect the extent of electrical injury: voltage (V), resistance (R), amperage (I), type of current, current pathway, and duration of contact.

Voltage is the electric pressure that causes current to flow. With 1000 V as the cutoff, injuries have been arbitrarily classified into high voltage and low voltage. [50] Voltage in high-tension transmission lines exceeds 100,000 V. The voltage in distribution lines is reduced to 7000 to 8000 V and further stepped down to 110 V (North America) or 220 V (Europe) before delivery to homes. [104] In lightning strike, the electric pressure generated between clouds and earth commonly exceeds 107 V.

Current is the flow of electrons per second and is measured in amperes (A). It is of two types, alternating current or AC and direct current or DC. Injuries caused by electricity are almost entirely attributable to AC, whereas lightning is DC. AC is three times more dangerous than DC of the same voltage. [50] [92] DC causes a single muscle contraction and throws the victim away from the source and thus reduces time of contact. Lightning generates peak DC of 20,000 to 40,000 A for a span of 1 to 3 microseconds and a continuing current of hundreds of amperes occurs for tens of milliseconds after. [62] The physical effects of such massive amounts of current flowing through or around the human body in an incredibly short period are unique. AC on the other hand causes repetitive muscle stimulation or tetany at a frequency of 50 to 60 Hz with current flows as low as 8 to 22 mA. [28] Most often contact with the source is through the hand and since flexors of the arm are stronger than extensors, the victim tends to grip the source and thus prolong the contact. The amount of AC needed to cause injury increases in proportion to its frequency, and at 10 kHz, a 20-mA current may not even be perceived. [44] An AC of 20 to 30 mA can cause paralysis of respiratory muscles and at 50 to 150 mA can cause ventricular fibrillation. [17] [104]

Resistance depends on area of contact, pressure applied, magnitude and duration of current flow, and presence of moisture. [36] The most important resistor to the flow of current is skin. Dry skin over palms and soles has a resistance of approximately 100,000 ohms and drops to as low as 2500 ohms when moist. Immersion in water further drops

skin resistance to 1500 ohms. [50] The extremely short duration of contact and the wet skin prevent skin breakdown in lightning injuries. Instead the current travels on the skin surface and discharges to the ground in a phenomenon known as flashover. [39] However, if the victim is well grounded, e.g., wearing metal cleats, it will travel through the body causing more injury. [77] Resistance of bone, fat, and tendons exceeds that of dry skin, whereas muscle, blood vessels, and nervous tissue exhibit much lower resistance. [50] It has been suggested that in high-tension electrical injuries the internal milieu acts as a single uniform resistance and the cross-sectional area of the part of body involved is more important than resistance of individual tissues. [5] [47] [69] [87] Extensive damage is seen in tissues with a smaller cross-sectional area as the321current density is higher. [47] [91] [97] This may explain why serious injuries to extremities are often seen but major injury to the trunk is rare. [5] [16] [31] [43]

Current pathway in the body plays a crucial role in determining injury to vital organs, including the central nervous system, respiratory system, heart, and pregnant uterus in women. [19] [32] [37] [60] [91] A vertical pathway, parallel to the body's axis, is more dangerous with a higher incidence of respiratory arrest, ventricular fibrillation, fetal deaths, and central nervous system (CNS) complications than hand-to-hand pathway. A current pathway entirely below the symphysis pubis is unlikely to cause any life-threatening injury.

Thermal energy (E) generated by passage of electric current is determined by the formula E= I2 RT where T is the duration of contact. Heat is measured in joule (J). It can be seen that prolonged contact with the source of electricity, as occurs commonly with AC, causes greater heat and more injury. In lightning strikes, the duration of contact is measured in milliseconds and, consequently, serious burns are infrequently seen. If the area of contact is large the thermal energy is dissipated over a larger area and burns will be less serious. [47] [91] The most common heat injury in both electrical and lightning injuries is arc burns and splash burns. [97] Electric arc has a temperature in excess of 3000°C and occurs owing to poor contact between tissue and source. [11] [81] It is seen on the volar surface of the forearm, the elbow, and the axilla and is usually associated with an entry wound of the palm with electrical injuries. [16] [49] [50] In lightning injuries the head or neck is usually the point of contact. The high temperature can cause severe burns or ignition of clothing or of surrounding combustible materials, causing flame burns. If the current spreads over a larger area a partial-thickness splash burn results. On the other hand if a major portion of current flows through the victim, deep electrothermal burns may result.

Several variables determine the nature and extent of injuries caused by electricity. A salient feature is the presence of extensive deep injuries with only minimal superficial evidence. This has led to the comparison of electrical injuries to crush injury. [6] As in crush injury, myoglobinuria is seen in serious electrical injuries. Besides burn injuries to skin and deeper tissues, electricity can injure the heart, the central nervous system, and the viscera. The extent of injuries from lightning depends on how the victim is struck. A direct strike results in maximum damage and most often involves an open space with the

victim in contact with a metal object. [39] Splash or side flash occurs when the current jumps to the victim from another object or person presumably because that pathway offers lower resistance. [39] If lightning strikes the ground near the victim, a potential difference may exist between the victim's legs; this difference causes the current to enter the body through one leg and exit through the other. This is referred to as stride potential or step voltage. [25] Besides blunt injury caused by a fall or a severe muscle contraction, lightning can cause blunt trauma in a unique fashion. The peak temperature in the lightning stroke channel rises within milliseconds to 30,000 K, which is five times hotter than the surface of the sun. [62] This generates a cylindrical shock wave of as much as 20 atm owing to the heating of air in the channel and results in mechanical trauma to any organ in its path as it decays. [65]

MECHANISM OF INJURIESBurns

Electricity can result in partial-thickness skin burns, full-thickness burns, or more extensive burns with injury to deeper tissue of the body. The patient322has a true high-tension injury when the burn extends deeper than skin and subcutaneous fat. More superficial injuries are often caused by flash burns or splash burns and cause only local erythema or partial-thickness burns. [6] [69] In a study of 217 accidental deaths caused by electrical injuries, visible electric burns were found in 57% of low-voltage deaths and in 96% of high-voltage victims. [104] It has been estimated that 20 to 35 mA/mm2 for 20 seconds raises skin temperature to 50°C, causing first-degree burns with swelling and blistering of skin [97] ; 75 mA/mm2 for the same time causes charring and perforation of skin by raising the temperature to 90°C. [17] Contact with the source of current occurs most often with hands. [16] [84] The estimation of surface burns so as to guide therapy (rule of 9's) may lead to fatal mistakes as minor superficial burns may hide massive coagulation necrosis of muscle and other deep tissues. [11] [15] [31] [69] As mentioned above, most of the damage is concentrated in the extremities. [43] [98] Bony structures are more resistant to electricity and retain heat longer than muscle. Therefore, a central core of necrotic muscle with relative sparing of superficial muscle is sometimes seen. [48] In children who bite or suck on an electrical cord, the current arcs through the lips causing burns to the oral structures. [8] [38] An eschar may form, covering the labial artery, and serious bleeding occurs when it falls off or is dislodged. [91]

Cooper [23] described an 89% incidence of burns with lightning injury, but only 5% had deep burns. The short duration and flashover effect prevents deep burns in most cases. The cutaneous manifestations in one series included feathering pattern, erythema with blistering, flash burns, contact burns (from metal), linear charring, and, most common of all, punctate full-thickness skin loss. [3] Punctate full-thickness skin loss is a characteristic feature with depressed central area of necrosis surrounded by congestion. The feathering pattern, also called Lichtenberg figures, is not a true burn. Various theories such as electron shower, travel of current along lines of moisture or superficial

vasculature, and even fractals have been hypothesized to explain their occurrence. [83] They typically disappear within 24 hours even in the postmortem state, and along with the punctate full-thickness burns, are pathognomonic of lightning injury. [10] [101]Vascular

Because of the crush-injury pattern of electrical burns, compartment syndrome occurs in extremities, thereby compromising circulation. [72] Cyanosis of distal uninjured skin, impaired capillary filling in the nail beds, progressive neurologic changes, and brawny edema with extreme tightness of muscle compartments on palpation are urgent indications for fasciotomy. [31] Electric current directly damages blood vessels. In larger arteries, rapid flow dissipates the heat, but delayed thrombosis may be seen because of medial necrosis, leading to delayed aneurysm formation and rupture of vessel with secondary hemorrhage. [31] [72] The high temperature produces coagulation necrosis and occlusion of small vessels, and nutrient branches supplying muscle are particularly susceptible. [15] [48] On arteriography this is revealed as arterial pruning proximal to occlusion and indicates a skip area of irreversible muscle injury. This may give the impression of progressive muscle necrosis, but in reality, the damage occurs at time of electrical injury. [47] [48] Coagulation necrosis and deep injury to vessels and muscle have only rarely been described with lightning injuries. [22] [40] [106] However, lightning may gain access to internal organs through cranial orifices such as eyes, ears, and mouth, resulting in considerable damage. [2] Cranial burns and leg burns are poor prognostic factors with 38% and 30% mortality, respectively, in a series by Cooper. [23]323Cardiac

Patients in whom the electric current takes a vertical pathway are at high risk for cardiac injury. [19] [52] Arrhythmias are frequently seen and result from passage of current through the heart or damage to conducting pathways. [16] [29] [60] Damage to myocardium is uncommon and occurs because of heat injury, as seen with skeletal muscle, or by coronary spasm, causing myocardial ischemia or infarction. [56] [63] [105] James et al [51] have postulated that in immediately fatal electrocution, electric current itself causes a brief but very powerful positive inotropic stimulus that results in typical finding of patchy contraction band necrosis on necropsy.Arrhythmias

DC current and high-tension AC current are more likely to cause ventricular asystole, whereas low-tension AC produces ventricular fibrillation. [68] [86] [92] Therefore, ventricular fibrillation must be considered if a household electrical injury results in cardiac arrest. The commonest ECG abnormalities, however, are sinus tachycardia, and nonspecific ST-T wave changes that resolve spontaneously. [43] [59] [92] [102] Other nonfatal arrhythmias seen are atrial and ventricular ectopy, atrial fibrillation, first- and second-degree heart block, bundle branch block, and QT interval prolongation. [16] [29] [31] [92] Sinus and atrioventricular nodes are especially vulnerable to AC current, and if affected, can result in long-term sequelae. [24] [51] Chronic arrythmogenic foci can arise in the heart owing to patchy necrosis at time of electrical injury and subsequent fibrosis. [53] The effect of lightning on the heart has been described as cosmic cardioversion and

results in ventricular standstill. [7] Automaticity results in spontaneous return to sinus rhythm, but often, the accompanying respiratory arrest persists. [82] [93] [94] This causes a secondary deterioration of the rhythm to ventricular fibrillation and asystole, which is more resistant to therapy than the first cardiac arrest. [22] [25] Some reports have described ventricular fibrillation as the initial event in cardiac arrest from lightning injury. [57] [101] In patients who do not suffer immediate arrest, the ECG abnormalities seen are most often nonspecific ST-T changes and interval delays that resolve uneventfully. [40] [65] [77] If initial electrocardiographic changes are not seen, it is unlikely that significant arrhythmias will occur later. [25] [80]Myocardial Damage

Myocardial damage in electrical injury may be difficult to determine clinically because typical symptoms and ECG changes are not seen. [19] [70] Because the damage is rarely transmural, ST-T elevation may not occur. [7] The role of creatinine kinase MB fraction (CK-MB) in helping to make a diagnosis has also been questioned. [8] [70] A study by Chandra et al [19] has suggested that vertical pathway and greater body surface burns increase the likelihood of the presence of myocardial damage. Coagulation necrosis may result in myocardial rupture in exceptional cases. [56] Coronary artery spasm can cause myocardial infarction, but this is probably responsible for only a small proportion of cases. [55] [63] [105] Massive release of adrenomedullary catecholamines and cardiogenic hypertensive chemoreflex may play a role in compounding the cardiac injury. [51] It has been speculated that the proximity of the right coronary artery to the chest wall in its initial course makes it especially vulnerable, producing damage to the sinus and the atrioventricular nodes as well as inferior-wall infarction. [18] [19] [51] [55] [70] [85] In lightning-related deaths, a review of 45 autopsies by Wetli [101] concluded that myocardial324infarction occurs rarely, if at all, and all four victims who had cardiac injury in his series showed evidence of myocardial contusion not infarction. CK-MB levels were thought to be unhelpful in determining injury. Lichtenberg et al [65] showed echocardiographic evidence of cardiac injury in three out of four patients who suffered a direct strike. They too believe the mechanism to be myocardial contusion that occurs from the shock wave generated by the lightning strike, as described above.

Nervous System

Neurologic involvement includes cerebral injury, spinal-cord lesions, peripheral nervous system involvement, and neuropsychological sequelae. [26] [41] [43] [52] Loss of consciousness, confusion, and poor recall immediately after high-voltage injury is common. [41] [43] [52] [90] Nearly half of all patients who have high-voltage injury have loss of consciousness at the scene, but full recovery is the general rule unless there is associated anoxia. [15] [41] Associated fall may result in intracranial hemorrhage or vertebral fractures, leading to central nervous system damage. [74] Cranial-nerve deficits and seizures may occur acutely. [16] [52] Spinal-cord injuries that manifest immediately have a better prognosis than those that present later, although partial recovery may occur. [64] [99] Levine et al [64] described three kinds of injury: amyotrophic lateral sclerosis,

ascending paralysis, and transverse myelitis with recovery occurring in only 2 of 40 patients. Upper-motor neuron-type of motor deficit is seen most often, with lower extremities being affected more commonly. [22] [64] [99] Paraplegia, quadriplegia, impotence, and bladder dysfunction have all been described. [11] [89] [99] Peripheral-nerve injuries and motor neuropathies occur owing to demyelinization, vacuolization, gliosis, and perivascular hemorrhage. [31] [98] Permanent damage generally does not extend beyond the area of local tissue damage, except when nerve entrapment occurs owing to scar formation. [98] The median and ulnar nerves are most frequently affected. [16] [31] [34] [41]

The most serious central nervous system complication of lightning injury is respiratory arrest caused by depression of the respiratory center. This can result in secondary cardiac arrest and death in a potentially salvageable victim. Common neurologic sequelae include loss of consciousness, confusion, paresis, and transient paralysis (keraunoparalysis). [23] [26] [96] Autonomic instability with hypertension, peripheral vasospasm, and transient paralysis are thought to occur owing to massive catecholamine release. [42] Extremities may be pulseless, cyanotic, and weak. [20] These resolve over a few hours, but residual effects such as neuritis, paraplegia, and amnesia can occur. [13] [25] Ten Duis [96] has described reflex sympathetic dystrophy as the most common autonomic disorder occurring after electrical injury. A series by Janus and Barrash [52] showed that cognitive impairment is common after serious electric injury with the most frequent areas of deficit being attention and memory, especially verbal memory. Depression, anxiety, and sometimes posttraumatic stress disorder may be seen years after injury. [52] [79]Viscera

Damage to the abdominal viscera occurs rarely. [75] High-tension injury to the gallbladder, pancreas, and small and large intestine has been described in case reports. Rarely, injuries may occur from low voltages. [95] [103] Curling's ulcers or stress ulceration of the gastric mucosa and adynamic ileus are the commonest gastrointestinal complications and are seen more often in patients who have325injuries from electricity than in patients who have burns caused by other causes. [16] [95] Ileus may be the only manifestation of more serious underlying gastrointestinal pathology, and if it persists for more than a few days, investigation by laparotomy should be considered. [103] Lung injury as a result of artificial electricity has been reported in a single case by Hartford and Ziffren. [43] Lightning can cause damage to viscera and lung by blunt trauma from the shock wave generated. [73]

Ophthalmologic

Cataracts are the most common injury to the eye and are seen most often from lightning injury but only rarely with electrical contact to the head. [1] [23] [37] [54] They may occur months to years after the injury and respond well to surgery. Complications such as corneal ulceration, iridocyclitis, hyphema, and vitreous hemorrhage are also commonly seen with lightning. [94] Autonomic disturbance may cause mydriasis, anisocoria, Horner's syndrome, failure of accommodation, and loss of red reflex. [54] This is

noteworthy because patients may present with dilated, nonreactive pupils as a result. [4] [40]Otologic

Rupture of the tympanic membrane occurs in more than 50% of patients who have lightning injury. [3] [23] [101] This causes a conductive hearing loss that is often accompanied by a sensorineural hearing loss at high frequencies. [12] [100] Injury to the facial nerve, otorrhea, tinnitus, vertigo, and nystagmus are other complications that occur less frequently. [12] [76]Musculoskeletal

Forceful tetanic contractions can cause fractures and tendon rupture, but falls resulting from the electric shock are the most important cause of injury to the musculoskeletal system. [16] Injury to the musculoskeletal system, occurring as a result of electrothermal burns, has been described above.

MANAGEMENTResuscitation and Triage

The rescuers must first and foremost create a safe environment in which to carry out emergency care. In the case of electricity, this may mean disconnecting the power supply before rescue is attempted. The patient who is alive immediately after a lightning strike or electrical accident will probably survive. Immediate attention must therefore be directed toward resuscitation of patients in respiratory or cardiac arrest. Keeping in mind the airway, breathing, and circulation (ABC), the airway is secured, breathing is established, and circulation is restored with advanced cardiac life support (ACLS) protocol as required. Electricity results in ventricular fibrillation and requires defibrillation in addition to respiratory support. Lightning causes asystole, and a sinus rhythm is oftentimes reestablished spontaneously; however, if respiratory support is not provided, a326secondary cardiac arrest caused by ventricular fibrillation can occur. Fixed, dilated pupils can occur after lightning injury owing to autonomic effects and are not a reason to stop resuscitation. [4] [42] Aggressive cardiopulmonary resuscitation is especially important in victims of lightning injury. [82] In serious electrical injury, aggressive fluid resuscitation must be started in the field. Normal saline or Ringer's lactate through a large bore intravenous line is appropriate. Fluid resuscitation is not needed in lightning injury. Once the decision to move the patient is made, precautions similar to any trauma victim are used. This includes immobilization of the cervical spine and any other obvious dislocation or fracture.

After successful resuscitation, an attempt is made to obtain a brief history. The nature of electrical contact, voltage, duration of contact, and any resulting fall have obvious implications. The speed with which resuscitation was commenced and duration of arrest, if any, affects prognosis. The patient's personal history, especially cardiac risk factors, is

also important. Each patient must receive a complete physical examination, including a detailed neurologic assessment and a thorough examination of the skin for any entry and exit wounds or other burns. After the clinician has assessed the seriousness of injury, the patient can be appropriately triaged. The low-voltage electrical injury victim with an intact neurologic examination and no skin burns probably does not need much more than reassurance and counseling regarding electrical hazards. [8] [27] [35] [38] The majority of lightning victims who survive suffer little injury because of the flashover effect and can similarly be discharged from the emergency room if the initial examination is unrevealing.Subsequent Care

After the initial stabilization, the most immediate risk is from cardiac arrhythmias. The majority of rhythm and conduction disturbances, however, run a benign course. [27] [35] Even in high-voltage injuries and patients who have burns, prolonged cardiac monitoring is required only if there is (1) history of arrest or loss of consciousness, (2) cardiac arrhythmia in the field or in the emergency room, (3) abnormal ECG on admission, and (4) admission is considered appropriate owing to burn size or age of patient. [80] Jensen et al [53] described case reports of delayed cardiac arrhythmias, and in cases in which the electric current passes through the thorax, 24 hours of cardiac monitoring may be appropriate. A small number of patients who have high-tension electrical injury may suffer from myocardial damage. CK-MB elevation, lactate dehydrogenase (LDH) isoenzymes, and ECG changes are unreliable clues. [8] [19] [58] [70] The role of newer cardiac troponins in assessing myocardial injury has not been defined. Echocardiography may show focal wall motion abnormalities and a technetium pyrophosphate scan of the heart has also been used. [18] Hemodynamic support and antiarrhythmics are used as indicated. Reperfusion therapy, including thrombolytics or percutaneous transluminal coronary angioplasty, has no role in management except if there is angiographically proved occlusion of coronary vessel. [18] A judicious use of fluids is necessary to prevent pulmonary edema in patients who have myocardial damage.

Loss of consciousness is common in high-tension electrical injury and lightning victims. Prolonged unconsciousness should prompt the clinician to perform imaging studies of the head to exclude intracranial damage caused by falls or direct injury by electric current. EEGs are generally believed to be unhelpful except when seizures occur. [52] Radiographs of cervical spine are required for excluding fracture or dislocation before neck immobilization can be discontinued.327Lightning victims often have keraunoparalysis with paraplegia or quadriplegia that resolves over a short period. This may be accompanied with autonomic instability that manifests as hypertension or cold, pulseless, and cyanotic extremities but that also resolves in a few hours. [42] Patients who have prolonged paresis or paralysis of extremities may have spinal-cord injury. Spine radiographs exclude vertebral fractures as a cause of spinal cord injury.

Fluid resuscitation should be instituted as soon as possible in victims of high-voltage injury. [16] [102] As with crush injury, the risk of rhabdomyolysis is high. The goal

should be to maintain a urine output of 70 to 100 mL/h until urine is cleared of pigment after which urine output is kept at 50 mL/h. [5] [69] Alkaline diuresis with intravenous sodium bicarbonate may improve clearance of myoglobin. Osmotic diuresis with mannitol can be tried in patients who have increased pigment. [11] If compartment syndrome has been excluded, early amputation may be necessary when there is persistent myoglobinuria. [11] Hemodialysis is instituted if the patient is in acute renal failure. Normal saline and Ringer's lactate are appropriate choices for initial fluid resuscitation. [30] The fluid requirement is approximately 1.7 times the calculated fluid requirement for the percentage of body surface area burnt by standard formulas. [69] Because of large fluid shifts, close monitoring of electrolytes is also necessary with replacement as needed.

All patients who have serious burn injuries should receive tetanus prophylaxis. The role of antibiotic prophylaxis is controversial, and some authors recommend penicillin to prevent clostridial myositis. [31] Skin burns are cleaned, and after initial debridement, open wounds are covered with topical antibiotics such as silver sulfadiazine and mafenide acetate and dry dressings are placed on them. [16] Mafenide can better penetrate eschar and is preferred except in large burns for which a generous amount of antibiotic may be needed, and mafenide may cause metabolic acidosis by inhibition of carbonic anhydrase. Homografting with serial debridement is done over several days until the wound is clear of all necrotic tissue, and then a split-thickness autograft is applied. [11] With burns of the oral commissure in children, parents must remain vigilant of profuse bleeding that can occur once the labial artery is exposed by removal of eschar. Conservative management with delay of any reconstruction by at least 6 to 9 months provides the best cosmetic results. [45] [78] Referral to an oral and maxillofacial surgeon may be appropriate for follow-up of other late complications. [88] The characteristic punctate burns seen in lightning require only dressing with topical antibiotics and heal by themselves, often without scarring. [16] It is uncommon to see severe burns in lightning injury. [25] [33]

Patients who sustain more extensive burns should be considered for transfer to a specialized burn unit. Intense swelling of extremities requires early exploration and fasciotomy to prevent more extensive damage caused by compartment syndrome. [11] [69] [91] [102] Frequent, periodic assessments of peripheral circulation and neurologic checks can identify a compromised extremity. [15] [31] The fasciotomy incision must extend through the skin, subcutaneous tissue, and investing fascia of all muscle compartments. [5] [11] It may be very difficult initially to tell viable from unviable tissue, and repeat exploration and debridement are often required. [6] [102] Despite the best efforts of physicians, amputations are necessary in a proportion of patients. [15] [31] [34] [102] In such cases, the level of injury must be accurately determined. Delaying the amputation by a few days stabilizes the patient for general anesthesia and also helps better define the level of amputation. [11] [16] Arteriography has been used to better define the level of amputation; however, it only reveals blockage in larger vessels and does not always identify injury to nutrient vessels that correspond to areas of skip necrosis. [5] [48]328Other methods such as technetium muscle scans, xenon-133 washout, and frozen-section microscopy have also met with only limited success. [15] [21] [46] [81]

In patients who have persistent adynamic ileus beyond a few days, an abdominal CT scan, peritoneal lavage, or exploratory laparotomy may be needed to confirm the diagnosis of injury to abdominal organs. [103] Because of the multiplicity of lesions usually seen in cases with abdominal injuries, a second-look operation at 2 to 5 days after the initial repair is advocated. [11] Gastrointestinal prophylaxis with acid suppressants should be provided to all patients who have serious injury.

Once the patient is stabilized, a careful otologic examination and audiogram may reveal hearing loss. Repair is deferred for several months, as the tympanic membrane may heal spontaneously. The delay also permits vascularization of damaged tissue and improves the success of tympanoplasty or tympanotomy. [12] It is useful to document an ophthalmologic examination in patients who have contact near the head, in case cataracts develop later on. Spinal-cord injury and peripheral-nerve injury may manifest only after a few days. Early institution of physical therapy helps minimize functional loss. [64] Counseling may be needed in patients who suffer psychiatric or behavioral sequelae.

SUMMARY

Electricity and lightning can cause injury in a variety of ways, some of which may remain hidden from the unsuspecting physician until it is too late. Prompt and, if necessary, prolonged resuscitation are of proven benefit. Particular attention must be paid to the patient who suffers high-voltage injury, and deep electrothermal burns or damage to vital organs should be excluded. Uncommonly late sequelae are seen, and such patients require appropriate care.References

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