When can a patient with rhabdomyolysis be considered for discharge?

When to Discharge a Patient with Rhabdomyolysis

A patient with rhabdomyolysis can be safely discharged when CPK levels are below 5,000 IU/L with a clear downward trend, renal function is normal or at baseline, electrolytes are corrected, adequate urine output is established (>0.5 mL/kg/hr), and compartment syndrome has been ruled out. 1

Essential Discharge Criteria

CPK Level Requirements

• CPK must be below 5,000 IU/L with at least two consecutive measurements showing a consistent downward trend 1
• The absolute CPK value at discharge is less important than demonstrating a clear declining trajectory 1, 2
• Most patients are discharged when CPK levels are downtrending, though discharge CPK values can range widely (1,410-94,665 U/L in one series) 2
• Continue intravenous fluids until CK levels fall below 1,000 U/L when possible 3

Renal Function Assessment

• Serum creatinine and BUN must be normal or at the patient's baseline before discharge 1
• Acute kidney injury must be resolved or stable, as this is the most significant complication of rhabdomyolysis 4, 3
• Urine output should be maintained at >0.5 mL/kg/hr (ideally 300 mL/hr during treatment) 1, 4

Electrolyte Correction

• All electrolyte abnormalities must be corrected, particularly potassium, calcium, and phosphate, as hyperkalemia can cause fatal cardiac arrhythmias 1
• Verify normal acid-base status 1

Compartment Syndrome Exclusion

• Clinical assessment must rule out compartment syndrome through evaluation for pain, muscle tension, paresthesia, and paresis 1
• This is particularly critical in traumatic rhabdomyolysis cases, which require longer monitoring for delayed compartment syndrome 1

Risk Stratification for Discharge Timing

Moderate Risk (CPK 5,000-15,000 IU/L)

• Requires close monitoring of renal function and electrolytes before discharge 1
• May be appropriate for earlier discharge if other criteria are met 1

High Risk (CPK >15,000 IU/L)

• Requires more aggressive hydration (>6L/day) and closer monitoring 1
• Longer hospitalization typically needed, with average length of stay correlating significantly with peak CPK levels 2
• Acute kidney injury occurs in 15-46% of cases, particularly when CPK exceeds 16,000 IU/L 5, 6

Special Populations Requiring Lower Thresholds

• Patients with pre-existing renal disease need more conservative discharge criteria with lower CPK thresholds 1
• Elderly patients and those with multiple comorbidities require extended monitoring 1

Mandatory Discharge Planning

Immediate Follow-Up Arrangements

• Schedule laboratory evaluation within 3-7 days after discharge to assess kidney recovery, including creatinine, BUN, and electrolyte panels 7
• Arrange continued follow-up with a nephrologist, particularly for patients with severe kidney injury, pre-existing chronic kidney disease, diabetes, or proteinuria 7

Medication Management

• Immediately discontinue all causative medications and supplements, including statins, creatine monohydrate, red yeast rice, wormwood oil, licorice, and Hydroxycut 7
• Adjust all renally excreted medications based on current kidney function 7
• Avoid nephrotoxic medications (NSAIDs, certain antibiotics) 1

Patient Instructions

• Maintain adequate oral hydration (at least 2-3L/day) to support continued myoglobin clearance 7, 1
• Cease the specific physical activity that triggered the rhabdomyolysis episode 7
• Avoid strenuous exercise until CPK levels normalize completely 1
• Return immediately for decreased urine output, dark urine, muscle pain, or weakness 1

Common Pitfalls to Avoid

• Never discharge patients with persistent electrolyte abnormalities, especially hyperkalemia, which can lead to cardiac arrest 1
• Do not discharge based solely on a single CPK value without confirming a downward trend 1
• Avoid delaying follow-up laboratory assessment beyond 7 days, as this can miss early signs of kidney function deterioration 7
• Do not assume urine myoglobin negativity excludes ongoing risk, as qualitative urine myoglobin is positive in only 19% of cases despite active rhabdomyolysis 6
• Never discharge without providing explicit hydration and follow-up instructions 1

Post-Discharge Monitoring Protocol

First Week

• Laboratory evaluation within 3-7 days including comprehensive metabolic panel and CPK 7
• Clinical assessment for signs of recurrent symptoms or declining renal function 7

Extended Surveillance

• Weekly monitoring of creatinine values if kidney function has not fully normalized 7
• Patients with more severe acute kidney disease require earlier and more frequent surveillance 7
• Continue nephrologist follow-up as kidney recovery can take weeks to months to fully assess 7