Lightning injuries
Background
There are 5 major means of injury from a lightning strike (direct, splash, contact, ground current, blunt trauma)[1]
Direct Strike
- Most often a fatal injury and occurs when the patient is hit with the lightning current.
- May cause penetrating injuries[2]
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 are in cardiac arrest should be treated FIRST. ("Resuscitate the Dead")
- If the patient does not suffer an immediate cardiac or respiratory arrest they have a good chance of survival[1]
- 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[3]
Cardiopulmonary
- Both cardiac and respiratory arrest may be present without evidence of external injury
- Ventricular dysrhythmias, asystole, and QT prolongation most common
- Although cardiac automaticity may spontaneously return, apnea may persist
- Duration of apnea rather than cardiac arrest is the critical prognostic factor
- Myocardial infarction after lightning injury is unusual
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
Vascular
- Vasomotor spasm may cause loss of pulse, coolness of extremities, loss of sensation
- Keraunoparalysis - temporary paralysis due to sympathetic nervous system activation and vascular spasm
- Resolves spontaneously
- Compartment syndrome is rarely the cause (skeletal muscle unaffected in strikes)
Ocular
- Cataracts may occur wks-yrs after injury (must document careful eye exam in all pts)
- Other injuries include vitreous hemorrhage, corneal abrasion, retinal detachment
Auditory
- Blast effect producing Tympanic Membrane Rupture is relatively common
Derm
- Lichtenberg figures (ferning pattern)
- Pathognomonic for lightning strike
- Occur due to electron showering over the skin, not true burn; disappear w/in 24hr
- Flash burns
- Similar to those found in arc welders; appear as mild erythema, may involve cornea
- Punctate burns
- Look similar to ciagarette burns; are full-thickness
- Contact burns
- 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
Differential Diagnosis
Diagnosis
Clinical diagnosis, based on H&P.
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
References
- ↑ 1.0 1.1 Gatewood M, Zane R. Lightning injuries. Emery Med Clin N Am. 2004; 22: 369-403
- ↑ Waes. O et al. "Thunderstruck": Penetrating Thoracic Injury From Lightning Strike. Annals of Emergency Medicine. 63(4). 2014. 457-458
- ↑ Cooper M. et al. Blumenthal R: Lightning Injuries. Auerbach PS ed: Wilderness Medicine, 6th ed. Philadelphia: Elsevier/Mosby; 2012