Lightning injuries

Background

There are 5 major means of injury from a lightning strike (direct, splash, contact, ground current, blunt trauma)

Direct Strike

• Most often a fatal injury and occurs when the patient is hit with the lightning current.

Splash Injury

• Occurs when the current "splashes" to the patient from another object which was struck first

Contact

• Occurs when the patient is in content with an object that is struck by lightning

Ground Current

• This is also known as step voltage and occurs when the current spreads out from the initial strike point and then travels through the patient's body

Blunt Trauma

• This is a secondary injury 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

• Emphasis is on early scene safety to prevent bystander and rescuer injury
• Triage is the reverse of triage for Mass Casualty Incidents with focus on the patients in cardiac arrest first.
• Patients with lightning injuries who appear to be dead should be treated FIRST at the scene. ("Resuscitate the Dead")
  • If the patient does not suffer an immediate cardiac or respiratory arrest they have a good chance of survival
• Emphasize early bystander CPR
• ACLS (Main) - Initial cardiac, respiratory monitoring and rhythm analysis for defibrillation.
• Fixed and dilated pupils do not indicate brain death. This can result from from Keraunoparalysis
• All patients require transport and burn patients should go to a Burn Center.
• Spinal precautions should be applied to all victims since the strike can produce violent muscle contractions even if there is not fall history.

Clinical Presentation

• Injuries often involve multiple organ systems in patients who survive

Cardiopulmonary

• Both cardiac and respiratory arrest may be present without evidence of external injury

1. Although cardiac automaticity may spontaneously return, apnea may persist
2. Duration of apnea rather than cardiac arrest is the critical prognostic factor
3. Myocardial infarction after lightning injury is unusual

Neuro

1. Symptoms are usually immediate and transient or delayed and permanent
2. Seizure, LOC, confusion, amnesia, extremity paralysis
3. Pupillary dilation or anisocoria may occur that is unrelated to brain injury

Vascular

1. Vasomotor spasm may cause loss of pulse, coolness of extremities, loss of sensation
2. Keraunoparalysis - temporary paralysis due to sympathetic nervous system activation and vascular spasm
   1. Resolves spontaneously
   2. Compartment syndrome is rarely the cause (skeletal muscle unaffected in strikes)

Ocular

1. Cataracts may occur wks-yrs after injury (must document careful eye exam in all pts)
2. Other injuries include vitreous hemorrhage, corneal abrasion, retinal detachment

Auditory

1. Blast effect producing Tympanic Membrane Rupture is relatively common

Derm

1. Lichtenberg figures (ferning pattern)
   1. Pathognomonic for lightning strike
   2. Occur due to electron showering over the skin, not true burn; disappear w/in 24hr
2. Flash burns
   1. Similar to those found in arc welders; appear as mild erythema, may involve cornea
3. Punctate burns
   1. Look similar to ciagarette burns; are full-thickness
4. Contact burns
   1. Occur when metal close to the skin is heated from the lightning current

Neuro

• Keraunoparalysis - a neurologic and muscular "stunning" that can follow lightning strikes and usually resolves. It is thought of as a neurologic phenomenon but is a result of arterial vasospasm from catecholamine release. It will resolve within hours.
  • Limb weakness, sensory abnormalities, absent pulses, cold temperature extremities

Ortho

• Compartment Syndrome and rhabdo are also common depending on the trajectory of the current

Diagnosis

Work-Up

• CBC, chem, total CK, UA
• ECG
• CT Brain(for patients with coma, AMS, confusion)
• Other imaging is directed toward visible or suspected injuries

Treatment

• 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)

Disposition

• Admit pts w/ persistent muscle pain or neuro, cardiac rhythm or vascular abnormalities
• Dishcarged pts require f/u to assess for delayed effects of lightning injury

See Also

• Electrical Injuries