Rosen & Barkin's 5-Minute Emergency Medicine Consult (239 page)

• Head/neck/ENT:
  
  • Common entry site for high-voltage injuries:
    
    • Facial and corneal burns
      
    • Perforated tympanic membranes
      
    • Cataracts and optic nerve atrophy may present initially, or delayed 4–6 mo
      
    • Intraocular hemorrhage, uveitis
      
    • Cervical spine injury
      
• Cardiovascular:
  
  • Cardiac arrest, asystole, and ventricular fibrillation are leading causes of death
    
  • Other arrhythmias and EKG findings: Sinus tachycardia, atrial fibrillation, premature ventricular contractions, transient ST-elevation, reversible QT-prolongation:
    
    • Sometimes delayed up to 12 hr
      
    • Usually resolve spontaneously
      
  • Myocardial damage occurs rarely:
    
    • Generally epicardial, not transmural
      
    • Damage does not follow distribution of coronary arteries
      
    • EKG will not show standard injury patterns
      
• Respiratory:
  
  • Brain injury causing respiratory center inhibition
    
  • Tetanic contraction/paralysis of chest wall/diaphragm muscles:
    
    • May cause respiratory arrest
      
  • Postcardiac arrest, respiratory arrest
    
  • Traumatic lung injury
    
  • Lung tissue itself appears resistant to electrical injury, probably owing to air content.
    
• Neurologic:
  
  • Respiratory arrest
    
  • Amnesia, transient confusion
    
  • Loss of consciousness, altered mental status, seizures, coma
    
  • Spinal cord injury:
    
    • May result from blunt trauma or DC effects (hand-to-hand flow)
      
    • Localized paresis up to/including quadriplegia
      
  • Long-term neurologic complications:
    
    • Seizures, peripheral nerve damage, spinal cord syndromes, psychiatric problems
      
• Vascular:
  
  • Muscle necrosis and compartment syndromes
    
  • Thrombosis in slow-moving venous system owing to coagulation
    
  • Intimal injury in fast-moving arterial system may lead to acute or delayed arterial malfunction.
    
• Renal failure secondary to myoglobinuria
  
• Skeletal system/orthopedics:
  
  • Supraphysiologic tetanic muscle contractions from electrostimulation
    
  • Classically described injuries:
    
    • Vertebral column fracture
      
    • Posterior shoulder dislocation
      
    • Femoral neck fracture
      
• Dermatologic:
  
  • Contact/ground wounds: Hands, feet, and head most common and most severe sites
    
  • “Kissing” burns from current exit and re-entry on flexor surfaces
    

Mouth burn most common <4 yr; sucking/biting on household electrical cord:

• Cosmetic deformity risk if commissure involved
  
• Delayed bleeding (3–5 days) from labial artery when eschar separates
  
• Risk of damage to developing dentition
  

Fetus much less resistant to electrical shock than mother:

• Obstetric consult or referral for all pregnant patients regardless of symptoms:
  
  • Risk of placental abruption or threatened miscarriage
    
  • Fetal monitoring if >20 wk gestation
    

• Determine whether exposure was high or low voltage, the duration and location of contact, or concomitant trauma
  
• If unwitnessed respiratory arrest or ventricular fibrillation in patient, consider electrical injury
  

Search the skin for entry/exit wounds and kiss/arch wounds at flexor surfaces

• Urinalysis for myoglobin
  
• EKG and cardiac enzymes for high-voltage victims, and low-voltage victims with cardiorespiratory complaints
  
• Cardiac monitoring indications:
  
  • Cardiac arrest
    
  • Loss of consciousness
    
  • Chest pain
    
  • Hypoxia
    
  • Abnormal EKG
    
  • Dysrhythmia in pre-hospital or ED setting
    
  • History of cardiac disease
    
  • Significant risk factors for coronary artery disease
    
  • Suspicion of conductive injury
    
  • Concomitant injury severe enough to warrant admission
    
• Prolonged monitoring is probably unnecessary in asymptomatic patients with normal EKG, no dysrhythmias, and exposure to <240 V
  

• For most exposures to household current, no testing is indicated:
  
  • Low-voltage burns can still cause dysrhythmias, seizures, and other complications if contact is near the chest or head
    
• Urinalysis for myoglobinuria
  
• Creatinine kinase, electrolytes, BUN, creatinine:
  
  • Positive urine myoglobin and/or high-voltage exposure
    
  • Provides baseline renal function, possible presence of hyperkalemia and metabolic acidosis
    
• Cardiac markers in:
  
  • Abnormal EKG or dysrhythmia
    
  • High-voltage exposures or low-voltage victims with cardiorespiratory complaints
    

Dictated by clinical indications

• Thermal burns from electrical arcing flash burn vs. deep electrothermal injury
  
• Instability owing to traumatic injuries vs. electrical burns
  

TREATMENT

• Secure scene; turn off power source for high-voltage incident
  
• Assume traumatic injury in unstable or unconscious patient:
  
  • Spinal immobilization
    
• Standard basic life support/advanced cardiac life support care
  
• Early CPR in postelectric shock arrest may allow time for heart to restart
  
• Splint fractures and dislocations
  
• Cover burns with clean, dry dressings
  

• ABCs
  
• Local wound care for thermal burns
  
• Immobilize/reduce fractures and dislocations
  

• IV fluid resuscitation:
  
  • Larger fluid volumes may be required owing to extensive 3rd spacing in injured muscle.
    
  • Rapid administration to reach urine output of 1 mL/kg/hr
    
  • Foley catheter
    
• Evaluate for myoglobinuria and prevent renal failure:
  
  • Maintain good urine output
    
  • IV sodium bicarbonate increases solubility of myoglobin in urine
    
  • Consider furosemide/mannitol
    
  • Monitor renal function
    
• Tetanus prophylaxis
  
• Pain control as required
  

• Bicarbonate: 1 ampule (50 mEq) IV, then add 2 ampules to 1 L of D
  ₅
  W to maintain urine pH >7.45
  
• Furosemide: 0.5 mg/kg IV
  
• Mannitol: 25 g (peds: 0.25–0.5 mg/kg) IV bolus, then 12.5 mg/kg/h IV titrated to urine flow >1 mL/kg/h
  

FOLLOW-UP

• Documented loss of consciousness
  
• Dysrhythmias, abnormal EKG, or evidence of myocardial damage
  
• Suspicion of deep tissue damage
  
• Myoglobinuria or acidosis
  
• Burn criteria for admit or transfer to burn center
  
• Traumatic injuries requiring admission
  
• Pregnant patients >20 wk gestation
  

• Minor, low-voltage injury (<240 V) with no associated injuries, normal physical exam, and asymptomatic
  
• Cutaneous burns or mild persistent symptoms with normal EKG and no urinary heme pigment
  
• Stable in ED after period of observation
  
• Discharge 1st-trimester patient with threatened miscarriage instructions
  
• Pediatric patients with isolated oral burns and close adult care
  

• Burn wound care
  
• Persistence of current symptoms or new delayed symptoms:
  
  • Neurology for delayed weakness, paresthesias
    
• Obstetrics for pregnant patients
  
• Dental or reconstructive surgery for pediatric oral burns
  

Ophthalmology for delayed cataracts in significant electrical current injuries

• Prolonged cardiac monitoring is probably unnecessary in asymptomatic patients with normal EKG, no dysrhythmias, and exposure to <240 V
  
• With significant electrical burn injuries, administer enough IV fluid to maintain adequate urine output and to stabilize the vital signs:
  
  • Extensive 3rd spacing may occur
    

• Bailey B, Gaudreault P, Thivierge RL. Cardiac monitoring of high-risk patients after an electrical injury: A prospective multicentre study.
  Emerg Med J
  . 2007;24(5):348–352.
  
• Fish JS, Theman K, Gomez M. Diagnosis of long-term sequelae after low-voltage electrical injury.
  J Burn Care Res
  . 2012;33(2):199–205.
  
• Spies C, Trohman RG. Narrative review: Electrocution and life-threatening electrical injuries.
  Ann Intern Med
  . 2006;145(7):531–537.
  

See Also (Topic, Algorithm, Electronic Media Element)

• Burns
  
• Lightning Injury
  
• Rhabdomyolysis
  

CODES