Lightning injuries

Background

  • Second most common storm-related injury
  • Approximately 30 million ground strikes per year

Injury Mechanisms[1]

  • Direct effect of electrical current on body
  • Electrical to thermal conversion of energy causing superficial and deep burns
  • Direct strike = patient is hit directly by lightning current
    • Often fatal and may cause penetrating injuries[2]
  • Splash Injury = current "splashes" to the patient from another object which is struck first
  • Conduction = patient is in contact with an object (e.g. metal fence, tree) that is struck by lightning
  • Ground current = Also known as step voltage. Occurs when the current spreads out from the initial strike point and then travels through the patient's body
    • Most common mechanism of injury
  • Blunt Trauma = Secondary injury pattern that results when the lightning causes a wave of force to propagate through the air to the patient or as a secondary object strikes the patient.

Prehospital Care

  • Reverse triage = in lightning-related MCI cases, care should be delivered to patients in cardiac and respiratory arrest first
    • Patients struck by lightning who are alive on EMS arrival will likely survive[1]
  • All patients should be transported, preferably to a burn center
  • Consider spinal precautions in all patients

Clinical Features

Superficial second degree burn from lightning injury.
Lichtenberg figure.
Patterned charring along the contact points of a metallic locket due to lightning strike.
Lightning-induced cataract.
Perforated TM

Injuries often involve multiple organ systems[3]

Cardiopulmonary

Neuro

  • Symptoms are usually immediate and transient or delayed and permanent
  • Seizure, LOC, confusion, amnesia, extremity paralysis
  • Pupillary dilation or anisocoria may occur that is unrelated to brain injury
    • Neuroprognostication should not be based on dilated pupils alone in setting of lightning strike[4]
  • Keraunoparalysis - neuromuscular "stunning" that usually resolves spontaneously within hours
    • Thought of as a neurologic phenomenon but actually result of arterial vasospasm from catecholamine release

Vascular

  • Vasomotor spasm may cause loss of distal pulses, coolness of extremities, loss of sensation
  • Keraunoparalysis - see above

Ocular

Auditory

Derm

  • Lichtenberg figures (ferning pattern) - pathognomonic for lightning strike
    • Occur due to electron showering over the skin leading to extravasation of RBC's, not a true burn; disappear within 24hr
  • Flash burns
    • Similar to those found in arc welders; appear as mild erythema, may involve cornea
  • Punctate burns
    • Look similar to cigarette burns; are full-thickness
  • Contact burns
    • Occur when metal close to the skin is heated from the lightning current

Ortho

Special Populations

  • 50% of pregnancies have fetal demise, though literature is sparse[5]
    • Third trimester appears to carry the greatest risk of adverse outcomes
    • Most surviving fetuses have no long term morbidity when carried to term
    • Any lightning strikes in pregnancy requires fetal monitoring, comprehensive testing in-hospital performed by Ob/Gyn

Differential Diagnosis

Burns

Evaluation

Work-Up

  • Exposure: complete and thorough physical exam head to toe
  • ECG
  • CBC
  • Chem
  • Total CK
  • UA - to evaluate for myoglobinuria
  • CT brain (for patients with coma, altered mental status, confusion)
  • Other imaging and workup is directed toward visible or suspected injuries

Diagnosis

  • Clinical diagnosis

Burn Thickness Chart[6]

Thickness Deepest Skin Structure Involved Pain & Sensation Appearance Expected Course Image
Superficial (first-degree)
  • Epidermis
  • Painful
  • Dry, erythema (no blisters)
  • Blanching (intact cap refill)
  • Heals without scarring, 5-10 days

Sunburn.jpg

Superficial Partial (second-degree)
  • Superficial dermis (papillary region)
  • Painful
  • Wet, pale pink, blisters
  • Blanching (intact cap refill)
  • Heals without scarring, <3 weeks

Hand2ndburn.jpg Scaldburn.jpg

Deep Partial (second-degree)
  • Deep dermis (reticular region)
  • Decreased sensation
  • Pale white-yellow, blisters
  • Does not blanch (absent cap refill)
  • Heals in 3-8 weeks
  • Likely to scar if healing >3 weeks
  • May require skin-graft if does not heal within 3 weeks

Major-2nd-degree-burn.jpg

Full (third-degree)
  • Hypodermis (subcutaneous tissue)
  • Decreased sensation
  • White, leathery
  • Does not blanch (absent cap refill)
  • Heals by contracture, >8 weeks
  • Almost always requires skin grafting

8-day-old-3rd-degree-burn.jpg

Fourth-degree
  • Underlying fat, muscle and bone
  • Decreased sensation
  • Black; charred with eschar
  • Does not blanch (absent cap refill)
  • Does not heal
  • Frequently requires amputation

Ожог кисть.jpg

Management

  • Reverse triage - prolonged on-scene CPR and ACLS protocol is indicated even if there are no initial signs of life
  • Aggressive resuscitation
    • Lightning-induced Cardiac Arrest has better prognosis than CAD-induced Cardiac Arrest
    • Hypotension is not an expected finding (i.e. suggests traumatic blood loss)
    • Maintain cervical spine precautions
    • Targeted Temperature Management between 32 and 36 degrees Celsius shown to be neuroprotective in setting of hypoxic ischemic encephalopathy after cardiac arrest

Disposition

  • Admit patients with persistent muscle pain or neuro, cardiac rhythm, or vascular abnormalities
  • Discharged patients require follow up to assess for delayed effects of lightning injury

See Also

References

  1. 1.0 1.1 Gatewood M, Zane R. Lightning injuries. Emery Med Clin N Am. 2004; 22: 369-403
  2. Waes. O et al. "Thunderstruck": Penetrating Thoracic Injury From Lightning Strike. Annals of Emergency Medicine. 63(4). 2014. 457-458
  3. Cooper M. et al. Blumenthal R: Lightning Injuries. Auerbach PS ed: Wilderness Medicine, 6th ed. Philadelphia: Elsevier/Mosby; 2012
  4. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3361158/
  5. Galster K et al. Lightning Strike in Pregnancy With Fetal Injury. Wilderness and Environmental Medicine. June 2016. Volume 27, Issue 2, Pages 287–290.
  6. Haines E, et al. Optimizing emergency management to reduce morbidity and mortality in pediatric burn patients. Pediatric Emergency Medicine Practice. 12(5):1-23. EB Medicine.