Electrical and Lightning Injuries

1. THE 2-MINUTE PHYSIOLOGY (Rapid Pathophysiology)

• Electrical Injuries (The "Crush" Equivalent): High-voltage electrical current passes through the body by taking the path of least resistance, which is typically the neurovascular bundles. Because the energy destroys tissues from the inside out, electrical injuries are pathophysiologically closer to a massive crush injury rather than a simple thermal burn. This deep tissue damage causes severe liquefactive and coagulation necrosis, triggering profound rhabdomyolysis and massive intracellular potassium release (hyperkalemia), often with minimal visible cutaneous injury.
• Lightning Strikes (The "Flashover" Phenomenon): Lightning involves millions of volts of direct current (DC) that typically "flashes over" the exterior of the patient's body rather than passing through deep internal tissue beds. The primary lethality stems from instantaneous, massive depolarization of the entire myocardium (causing asystole) and the medullary respiratory centers (causing respiratory paralysis). Because respiratory paralysis often outlasts the heart's return to automaticity, patients frequently suffer a secondary hypoxic cardiac arrest.

2. THE BEDSIDE ACTION PLAN (Rapid ER Management)

• Immediate Stabilization & Trauma Pathway: You must first verify that the victim has been safely separated from the electrical source. Because the intense shock causes tetanic muscle contractions and secondary blast effects, approach all victims through a trauma lens: initiate ATLS protocols with strict C-spine immobilization.
• Respiratory & Cardiac Resuscitation: Maintain a low threshold for advanced airway management due to respiratory muscle paralysis. Treat cardiac dysrhythmias strictly according to standard ACLS and PALS algorithms.
• Fluid Resuscitation & Critical Titration:
• Initiate aggressive IV hydration with Normal Saline or Lactated Ringer's (e.g., 20 mL/kg initial bolus in pediatrics).
• Critical Target: Because of the heavy myoglobin load from destroyed muscle, you must titrate fluids to maintain a brisk urine output of > 100 mL/hr in adults or > 1-2 mL/kg/hr in children.

3. THE DIAGNOSTIC GRID (Differential Diagnosis & Workup)

• Critical "Can't-Miss" Concomitant Diagnoses:
• Occult Hemorrhagic Shock: Hypotension is not an expected physiologic consequence of a lightning or electrical injury; if your patient is hypotensive, you must aggressively hunt for occult hemorrhage from blunt trauma (e.g., ruptured spleen from being thrown).
• Compartment Syndrome: Edema from deep muscular necrosis expands rapidly, requiring emergent fasciotomy despite benign-appearing skin.
• Prioritized Diagnostic Workup:
• Cardiac/Muscle Panel: CPK (creatine kinase) to quantify muscle destruction, serum troponin, and a basic metabolic panel specifically to monitor K+, BUN, and Creatinine.
• Renal Protection: Urinalysis and urine myoglobin to detect impending pigment nephropathy.
• Imaging: Complete trauma imaging, including C-spine X-rays to identify fractures/dislocations from tetanic contractions, and a CT Head for any persistent altered mental status or focal deficits.

4. THE VISUAL BOARD (ECG / POCUS / Imaging)

• The ECG Checklist: Mandatory in all moderate-to-severe exposures. Explicitly look for transient ST-segment elevations, prolonged QTc, conduction blocks, or ventricular dysrhythmias. While frank myocardial infarction (MI) is rarely the cause, the ST changes mimic it heavily.
• The Cutaneous Exam: Examine for specific entry and exit wounds to help map the current's path through the body. However, visually rely on assessing tense compartments rather than burns, as the lack of surface thermal injury frequently masks extensive deep tissue destruction.
• HEENT Exam in Lightning: Look specifically for tympanic membrane rupture, ocular injuries, and hearing difficulties, which are classic signs of the blast-like effect of a lightning flashover.

5. THE SCORING MATRIX (Risk Stratification & Guidelines)

• Mandatory Monitoring Guidelines: Any patient exposed to high-voltage electricity or a lightning strike who presents with syncope, altered mentation, focal neurological deficits, significant entry/exit burns, or persistent symptoms requires comprehensive lab testing.
• Disposition Cutoffs: Patients exhibiting ECG abnormalities (dysrhythmias, signs of injury) or evidence of significant local tissue injury must be admitted for 12 to 24 hours of continuous cardiac monitoring in an observation unit, step-down, or ICU setting.
• Surgical Escalation: High-voltage injuries with deep tissue involvement automatically warrant a specialized Burn Center consultation and surgical evaluation for fasciotomy.

6. THE DANGER ZONE (Pitfalls & Critical Actions)

• Pitfall (The Parkland Trap): Attempting to use the Parkland burn formula for high-voltage electrical injuries. The Parkland formula calculates volume based on visible cutaneous Total Body Surface Area (TBSA). Because electrical injuries cause massive invisible tissue destruction beneath the skin, the Parkland formula severely underestimates fluid requirements.
• Pitfall (The Airway Trap): Choosing Succinylcholine during rapid sequence intubation (RSI) for a patient with a significant electrical injury. The massive underlying muscle necrosis poses a lethal risk of hyperkalemic cardiac arrest.
• CRITICAL ACTION: You must continue aggressive, prolonged resuscitative efforts for lightning strike victims found in cardiac arrest. Unlike patients suffering out-of-hospital cardiac arrest from coronary artery disease, lightning victims have a remarkably better prognosis for neurologic recovery and survival if supported through their respiratory paralysis.

7. MCQ MASTERCLASS (Written Exam Tips)

• Buzzwords: "Hearing difficulties," "tympanic membrane rupture," or "patient found outside after thunderstorm." $\rightarrow$ Indicates a Lightning strike. The correct answer often centers on treating the asystole/respiratory arrest or evaluating HEENT/cardiac status rather than focusing on deep muscle burns.
• Buzzwords: "Electrician," "high-voltage line," or "deep pain with minimal skin burns." $\rightarrow$ The correct diagnostic focus is rhabdomyolysis.
• Common Distractor: A question stem asks for the best fluid management strategy in an electrician with a high-voltage arm injury. Distractors will include "Calculate the Parkland formula" or "Administer 2 Liters normal saline and stop." The correct answer will be "Administer IV fluids to maintain a urine output > 100 mL/hour" to flush myoglobin.
• Common Distractor: A patient presents comatose after an electrical injury. A distractor option will be "Declare brain death" or "Administer Mannitol." The correct answer is "Intubation and supportive care" as electrical respiratory paralysis and transient blocks are reversible, and Mannitol is reserved for herniation.

8. THE BOARDROOM SCRIPT (OSCE & Oral Board Tips)

• High-Stress Articulation: "I am first ensuring the scene is safe and the patient is disconnected from the electrical source. I will initiate standard ATLS protocols with strict C-spine immobilization, as this patient is at extremely high risk for occult fractures from severe tetanic muscle contractions and being thrown by the blast."
• Mandatory Physical Exam Maneuvers: "I am fully exposing the patient to map entry and exit wounds. I am palpating all extremity compartments for tenseness and checking serial pulses to evaluate for compartment syndrome, understanding that the skin exam may belie massive deep tissue necrosis."
• Communication Pearl (Resuscitation): "Nurse, please place the patient on continuous cardiac monitoring and obtain a stat ECG. We will initiate IV fluid resuscitation with Lactated Ringer's. We will not use the Parkland formula; instead, I want a Foley catheter placed so we can aggressively titrate our fluids to maintain a urine output of greater than 100 mL/hour to prevent pigment nephropathy from rhabdomyolysis. I am also calling Surgery for a possible fasciotomy."