From the Guidelines
The next steps for a patient with impaired renal function due to elevated creatinine should include a comprehensive evaluation to determine the cause and severity of kidney dysfunction, and according to the most recent guidelines, such as those from 1, do not discontinue renin-angiotensin system blockade for mild to moderate increases in serum creatinine (#30%) in the absence of signs of extracellular fluid volume depletion.
Initial Evaluation
The patient should undergo a complete blood count, comprehensive metabolic panel, urinalysis, and urine protein-to-creatinine ratio to assess the extent of kidney damage.
- Medication review is crucial to discontinue or adjust potentially nephrotoxic drugs such as NSAIDs, certain antibiotics, and contrast agents.
- Hydration status should be optimized with oral or IV fluids if dehydration is present.
Blood Pressure Control
Blood pressure control is essential, often using ACE inhibitors or ARBs like lisinopril (starting at 5-10mg daily) or losartan (25-50mg daily), which provide renoprotective effects by reducing intraglomerular pressure, as supported by guidelines from 1.
Dietary Modifications
Dietary modifications including sodium restriction (<2g/day), protein moderation (0.8g/kg/day), and potassium restriction may be necessary depending on the stage of kidney disease.
Monitoring
Regular monitoring of creatinine, estimated GFR, electrolytes, and blood pressure should be established, with frequency determined by severity, and adjustments to ACEi or ARB should be made based on serum creatinine and potassium levels, as outlined in 1. These interventions aim to prevent further kidney damage by addressing the underlying cause, reducing metabolic waste accumulation, and maintaining fluid-electrolyte balance while the kidneys recover or to slow progression of chronic kidney disease.
From the FDA Drug Label
Dose in Patients with Renal Impairment No dose adjustment of lisinopril tablets is required in patients with creatinine clearance > 30 mL/min. In patients with creatinine clearance ≥ 10 mL/min and ≤ 30 mL/min, reduce the initial dose of lisinopril tablets to half of the usual recommended dose i.e., hypertension, 5 mg; systolic heart failure, 2.5 mg and acute MI, 2. 5 mg. Up titrate as tolerated to a maximum of 40 mg daily. For patients on hemodialysis or creatinine clearance < 10 mL/min, the recommended initial dose is 2.5 mg once daily [see Use in Specific Populations (8.7)and Clinical Pharmacology (12.3)].
The next steps for a patient with impaired renal function due to elevated creatinine are to:
- Monitor renal function: Check creatinine clearance to determine the severity of renal impairment.
- Adjust dosage: Reduce the initial dose of lisinopril tablets to half of the usual recommended dose if creatinine clearance is ≥ 10 mL/min and ≤ 30 mL/min.
- Up titrate as tolerated: Increase the dose up to a maximum of 40 mg daily as tolerated by the patient.
- Consider alternative dosing: For patients on hemodialysis or creatinine clearance < 10 mL/min, the recommended initial dose is 2.5 mg once daily 2.
From the Research
Next Steps for Patients with Impaired Renal Function
The next steps for a patient with impaired renal function due to elevated creatinine involve several key considerations:
- Investigation to determine the potential reversibility of disease, evaluate prognosis, and optimize planning of care 3
- Referral to a nephrologist for patients with newly discovered renal insufficiency or an established, progressive increase in serum creatinine level 3
- Preparation for dialysis or transplantation, which requires at least 12 months of relatively frequent contact with a renal care team 3
Management and Treatment
Management of patients with elevated creatinine levels may involve the use of angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin-receptor blockers (ARBs), which have been shown to be effective in reducing urine albumin excretion and urine protein excretion 4
- However, the use of ACEIs and ARBs must be carefully considered, as they can be associated with adverse effects such as hypotension, renal function impairment, and hyperkalemia 5
- The safety of ACE inhibitor therapies in patients with chronic kidney disease (CKD) is a concern, and strategies to address safety concerns are needed 5
Monitoring and Follow-up
Monitoring of renal function is critical in patients with elevated creatinine levels, and serum creatinine is the most widely used functional biomarker of the kidney 6
- However, the use of serum creatinine as a marker of kidney function has substantial shortcomings, and understanding these limitations is critical for accurate interpretation of creatinine values 6
- Long-term changes in renal function in relation to ACEI/ARB dosing in patients with heart failure and CKD have been studied, and the results suggest that neither continuation of high doses of ACEI/ARB nor up-titration is related to adverse changes in longer-term renal function 7