What is the next appropriate step in managing a 55-year-old gentleman with rhabdomyolysis due to a lightning strike?

Management of Rhabdomyolysis in a Lightning Strike Victim

The next appropriate step in managing this 55-year-old gentleman with rhabdomyolysis due to lightning strike is to administer aggressive IV fluid resuscitation with normal saline (0.9% saline). This intervention is critical to prevent acute kidney injury, which is the most significant complication of rhabdomyolysis 1.

Pathophysiology and Assessment

Lightning strike causes massive electrical injury resulting in:

• Direct muscle damage leading to rhabdomyolysis
• Release of myoglobin into circulation
• Risk of acute kidney injury from myoglobin-induced tubular damage
• Potential electrolyte abnormalities (particularly hyperkalemia)

Key clinical considerations:

• Assess for signs of compartment syndrome (pain, tension, paresthesia, paresis)
• Monitor urine output and color (myoglobinuria presents as tea-colored urine)
• Check electrolytes, particularly potassium levels
• Monitor creatine phosphokinase (CPK) levels

Management Algorithm

1. Initial Fluid Resuscitation:

   • Begin IV normal saline (0.9%) at 1L/hour initially 1
   • Target urine output of at least 300 mL/hour 2
   • Avoid potassium-containing fluids like Lactated Ringer's solution 1

2. Monitoring:

   • Insert urinary catheter to monitor output
   • Regular assessment of electrolytes, especially potassium
   • Monitor CPK levels
   • Assess acid-base status

3. Volume Management:

   • Adjust fluid rate based on:
     • Clinical response
     • Urine output
     • Hemodynamic parameters
   • Continue aggressive hydration until CPK levels decrease to <1,000 U/L 2

4. Adjunctive Therapies (after initial fluid resuscitation):

   • Consider IV sodium bicarbonate if patient develops metabolic acidosis 1
   • Consider mannitol only if urine output goals aren't met despite adequate fluid resuscitation 1, 2

Why IV Fluids Over Other Options

Among the options presented:

• IV fluids (normal saline): Correct choice - dilutes nephrotoxic myoglobin, maintains renal perfusion, and helps prevent acute kidney injury 1, 3
• Oxygen: While important for overall care, not the priority intervention for rhabdomyolysis
• Fluid restriction: Contraindicated - would worsen kidney injury 1
• IV dopamine: Not indicated as first-line therapy for rhabdomyolysis
• IV furosemide (frusemide): Contraindicated initially - may worsen kidney injury by reducing intravascular volume when hydration is needed

Important Caveats

• Avoid potassium-containing fluids as patients may develop hyperkalemia from muscle breakdown 1
• Monitor for volume overload, especially in older patients or those with cardiac/renal dysfunction
• Watch for compartment syndrome requiring fasciotomy 1
• Recent evidence suggests that excessive fluid volumes (>6L/day) may not be beneficial in all cases and should be individualized based on severity 4
• Bicarbonate administration remains controversial - use primarily if acidosis develops rather than prophylactically 4

Early aggressive fluid resuscitation has reduced mortality in rhabdomyolysis from nearly 100% to <20% over the past decades 3. Prompt intervention is essential to preserve renal function and prevent life-threatening complications.