Ver el código de «Lightning injuries»

==Background==
*Second most common storm-related injury
*Approximately 30 million ground strikes per year

===Injury Mechanisms<ref name="gatewood">Gatewood M, Zane R. Lightning injuries. Emery Med Clin N Am. 2004; 22: 369-403</ref>===
*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<ref>Waes. O et al. "Thunderstruck": Penetrating Thoracic Injury From Lightning Strike. Annals of Emergency Medicine. 63(4). 2014. 457-458</ref>
*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 arrest|cardiac]] and respiratory arrest first
**Patients struck by lightning who are alive on EMS arrival will likely survive<ref name="gatewood" />
*All patients should be transported, preferably to a burn center
*Consider spinal precautions in all patients

==Clinical Features==
[[File:PMC5253516 icrp a 1275646 f0001 c.png|thumb|Superficial second degree burn from lightning injury.]]
[[File:PMC4763624 IJD-61-109-g002.png|thumb|Lichtenberg figure.]]
[[File:PMC4891493 CCR3-4-618-g001.png|thumb|Patterned charring along the contact points of a metallic locket due to lightning strike.]]
[[File:PMC3350295 CRIM.OPHMED2011-724395.003.png|thumb|Lightning-induced cataract.]]
[[File:PerforationTympan.jpg|thumb|Perforated TM]]
''Injuries often involve multiple organ systems<ref>Cooper M. et al. Blumenthal R: ''Lightning Injuries''. Auerbach PS ed: ''Wilderness Medicine'', 6th ed. Philadelphia: Elsevier/Mosby; 2012</ref>''
===Cardiopulmonary===
*Both [[cardiac arrest|cardiac]] and [[respiratory failure|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]], [[syncope|LOC]], [[confusion]], amnesia, extremity [[weakness|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<ref>https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3361158/</ref>
*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, [[numbness|loss of sensation]]
*Keraunoparalysis - see above

===Ocular===
*Cataracts may occur weeks to years after injury (must document careful eye exam in all patients)
*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 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===
*[[Compartment Syndrome]] and [[rhabdomyolysis]] are unlikely due to short duration of lightning current
*Associated with [[posterior shoulder dislocation]]

===Special Populations===
*50% of pregnancies have fetal demise, though literature is sparse<ref>Galster K et al. Lightning Strike in Pregnancy With Fetal Injury. Wilderness and Environmental Medicine. June 2016. Volume 27, Issue 2, Pages 287–290.</ref>
**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==
*[[Blast injury]]
{{Burn DDX}}

==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}}

==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
**[[therapeutic hypothermia|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==
*[[Electrical Injuries]]

==References==
<references/>

[[Category:Environmental]]
[[Category:EMS]]
[[Category:Trauma]]