Ver el código de «Rhabdomyolysis»

==Background==
*Breakdown of skeletal muscle releasing intracellular contents into the circulation
*Key toxins: myoglobin (nephrotoxic), creatine kinase (CK), potassium, phosphate, uric acid
*Acute kidney injury (AKI) occurs in 15-40% of cases<ref name="bosch">Bosch X, et al. Rhabdomyolysis and acute kidney injury. ''N Engl J Med''. 2009;361(1):62-72. PMID 19571284.</ref>
*Overall mortality ~5%; higher with AKI, DIC, or [[Compartment syndrome|compartment syndrome]]

==Etiology==
*Trauma / Crush injury (most common worldwide)
*'''Exertional''' (exercise, seizures, agitation, status epilepticus)
*Drug/toxin-induced
**Statins (especially with interacting drugs)
**[[Cocaine toxicity|Cocaine]], [[Amphetamine toxicity|amphetamines]], MDMA, [[Ethanol toxicity|alcohol]]
**[[Neuroleptic malignant syndrome|NMS]], [[Serotonin syndrome]], [[Malignant hyperthermia]]
*Prolonged immobilization (found down, intraoperative)
*[[Hypokalemia]], [[Hypophosphatemia]], [[Hyponatremia]]
*[[Heat stroke]]
*Infections (influenza, COVID-19, Legionella)
*Hypothermia, [[Electrical injury|electrical injuries]]

==Clinical Features==
*Classic triad: myalgias, weakness, dark urine (tea/cola-colored)
**Full triad present in <10% of cases
*Muscle tenderness, swelling, and stiffness
*May be asymptomatic with only lab abnormalities
*Complications:
**[[Hyperkalemia]] (can cause [[Cardiac dysrhythmia|cardiac dysrhythmias]]) — '''life-threatening'''
**[[Acute kidney injury]] (oliguria, anuria)
**[[Compartment syndrome]]
**[[DIC]]
**Hypocalcemia (early), hypercalcemia (recovery phase)
**Metabolic acidosis

==Evaluation==
*Creatine kinase (CK) — diagnostic marker
**CK >5x upper limit of normal (typically >1,000 U/L) diagnostic
**CK >5,000 U/L: significant risk of AKI
**Peak CK at 24-72 hours; monitor serial levels
*Urinalysis: urine dipstick positive for "blood" but no RBCs on microscopy (myoglobinuria)
*BMP: potassium (may be severely elevated), creatinine, BUN, calcium, phosphate, bicarbonate
*CBC, LDH, uric acid, coagulation studies
*ECG — evaluate for [[Hyperkalemia|hyperkalemia]] changes (peaked T waves, wide QRS)
*Consider compartment pressures if clinical concern

==Management==
===Aggressive IV Fluid Resuscitation===
*Cornerstone of treatment
*Normal saline at 200-300 mL/hr (or 1-2 L/hr initially if severely hypovolemic)<ref name="scharman">Scharman EJ, et al. Prevention of kidney injury following rhabdomyolysis: a systematic review. ''Ann Pharmacother''. 2013;47(1):90-105. PMID 23324509.</ref>
*Target urine output 200-300 mL/hr until CK trending down and urine clears
*Monitor for fluid overload, especially in elderly and those with cardiac/renal disease
*Bicarbonate drip (150 mEq NaHCO3 in 1 L D5W) may be considered to alkalinize urine (target urine pH >6.5) — evidence is limited

===Treat Hyperkalemia===
*See [[Hyperkalemia]] for detailed management
*Calcium gluconate 10% 10 mL IV for cardiac membrane stabilization if ECG changes
*Insulin 10 units regular IV + D50W 50 mL IV
*[[Sodium bicarbonate]], [[Albuterol]] nebulizer, [[Kayexalate]] or patiromer
*Emergent [[Hemodialysis|dialysis]] if refractory

===Other===
*Treat underlying cause (cool if [[Heat stroke|hyperthermic]], correct electrolytes)
*Avoid nephrotoxins (NSAIDs, contrast dye, aminoglycosides)
*[[Compartment syndrome]]: emergent fasciotomy if pressures >30 mmHg or clinical diagnosis
*Monitor for and treat [[DIC]] if present

==Disposition==
*Admit patients with:
**CK >5,000 U/L
**AKI (elevated creatinine)
**[[Hyperkalemia]] or other electrolyte derangements
**Ongoing symptoms or rising CK
*Discharge may be considered for mild rhabdomyolysis (CK <5,000, normal renal function, normal K) with close follow-up and oral hydration

==See Also==
*[[Hyperkalemia]]
*[[Acute kidney injury]]
*[[Compartment syndrome]]
*[[Crush injury]]
*[[Heat stroke]]

==References==
<references/>

[[Category:Renal]]
[[Category:Orthopedics]]