From the Guidelines
For a patient with a BN of 34 and creatinine of 1.43, I strongly recommend an invasive strategy with careful consideration of renal protective measures, as this patient has moderate kidney dysfunction. This approach is based on the guidelines from the American College of Cardiology Foundation/American Heart Association task force on practice guidelines, which suggest that an invasive strategy is reasonable in patients with mild (stage 2) and moderate (stage 3) chronic kidney disease (CKD) 1. Given the patient's creatinine level of 1.43, it is essential to adjust medication dosing according to estimated glomerular filtration rate (eGFR) and to avoid nephrotoxic medications, including NSAIDs, certain antibiotics, and contrast agents, unless absolutely necessary and with appropriate precautions 1. Some key considerations include:
- Ensuring adequate hydration with intravenous fluids if the patient is volume depleted
- Discontinuing or dose-adjusting nephrotoxic medications
- Adjusting medication dosing according to eGFR
- Daily monitoring of renal function, electrolytes, and fluid balance
- Dietary modifications, such as protein restriction, may be necessary depending on electrolyte levels
- Investigating the underlying cause of renal dysfunction through urinalysis, renal ultrasound, and additional laboratory tests It is also crucial to use isosmolar contrast agents when angiography is necessary, as they are associated with lower rates of contrast-induced nephropathy in patients with CKD 1. Overall, the management of this patient requires a careful balance between addressing the cardiovascular issues and protecting the kidneys from further damage.
From the FDA Drug Label
In acute myocardial infarction, treatment with lisinopril should be initiated with caution in patients with evidence of renal dysfunction, defined as serum creatinine concentration exceeding 2 mg/dL If renal dysfunction develops during treatment with lisinopril (serum creatinine concentration exceeding 3 mg/dL or a doubling from the pretreatment value) then the physician should consider withdrawal of lisinopril.
The patient has a creatinine level of 1.43, which is below the threshold of 2 mg/dL. However, caution is still advised when initiating treatment with lisinopril in patients with renal dysfunction.
- The patient's renal function should be monitored during the first few weeks of therapy.
- Dosage reduction and/or discontinuation of the diuretic and/or lisinopril may be required if renal dysfunction develops.
- The physician should consider withdrawal of lisinopril if renal dysfunction develops during treatment 2.
From the Research
Patient Assessment
- The patient has a Blood Urea Nitrogen (BN) of 34 and a creatinine level of 1.43, indicating potential kidney function impairment.
- Serum creatinine is a widely used biomarker for kidney function, but its interpretation can be challenging due to substantial shortcomings 3.
Intervention Considerations
- Accurate estimation of static kidney function and detection of changes in kidney function are crucial for appropriate intervention.
- Understanding the pathways involved in creatinine generation and metabolism, as well as the techniques for measuring creatinine concentrations, is essential for interpreting creatinine values and translating them into changes in kidney function 3.
- Alternative functional biomarkers of the kidney may provide additional information for patient assessment and intervention planning 3.
Clinical Decision-Making
- Clinicians should consider the limitations of serum creatinine as a biomarker and interpret results in the context of the patient's overall clinical presentation.
- A comprehensive assessment of the patient's kidney function, including the use of alternative biomarkers and clinical evaluation, is necessary to determine the appropriate intervention 3.