From the Guidelines
The patient's elevated BUN, creatinine, and CK levels indicate significant renal dysfunction and muscle damage, necessitating immediate attention and postponement of elective surgery until these abnormalities are investigated and stabilized. The elevated BUN (29 mg/dL) and creatinine (2.2 mg/dL) suggest acute kidney injury or chronic kidney disease, while the markedly elevated CK (creatine kinase) level of 3385 indicates significant muscle damage (rhabdomyolysis) 1. According to the 2014 ESC/ESA guidelines on non-cardiac surgery, the presence of pre-operative creatinine elevation is a significant risk factor for postoperative acute kidney injury (AKI) and increased morbidity and mortality 1.
Key Considerations
- The patient's renal function should be further evaluated using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formula to calculate the estimated glomerular filtration rate (eGFR) 1.
- The patient should undergo immediate nephrology consultation to determine the underlying cause of the renal dysfunction and muscle damage.
- Intravenous hydration with normal saline should be initiated to prevent further kidney injury, and serial monitoring of renal function and CK levels should be performed.
- Potential causes of this presentation, such as medication effects (particularly statins), trauma, excessive exercise, seizures, or infections, should be evaluated, and any nephrotoxic medications should be discontinued 1.
Recommendations
- Postpone elective surgery until the patient's renal function and CK levels are stabilized or improved.
- Initiate measures to prevent further kidney injury, such as maintaining adequate intravascular volume for renal perfusion and using vasopressors if necessary 1.
- Evaluate the patient for underlying conditions that could explain both the renal dysfunction and muscle breakdown, and manage these conditions accordingly.
From the Research
Laboratory Results
- BUN: 29
- Creatinine: 2.2
- CK: 3385 in a 65-year-old male preop exam
Possible Causes and Implications
- Elevated CK levels can be caused by various factors, including muscle damage, exertional rhabdomyolysis, or other medical conditions 2, 3, 4
- The patient's high CK level may be a concern, but it is essential to consider other factors, such as age, BMI, and operating room time, which can also impact CK levels 5
- The patient's creatinine level is also elevated, which may indicate impaired renal function 5, 6
Renal Function and CK Elevation
- Studies have shown that elevated CK levels can be associated with a decline in renal function, particularly in the immediate postoperative period 5
- However, other research suggests that exertional muscle damage can cause profound CK elevations without renal impairment 2
- The patient's BUN and creatinine levels should be monitored closely to assess renal function and determine the best course of action 6
Diagnostic Approach
- A comprehensive diagnostic approach is necessary to determine the cause of the patient's elevated CK level and impaired renal function 3, 4
- This may include repeat testing, evaluating for nonneuromuscular causes, and considering a workup for neuromuscular causes 4
- The patient's medical history, physical examination, and laboratory results should be carefully evaluated to guide further testing and management 3