What are the management strategies for patients with impaired kidney function?

Management Strategies for Patients with Impaired Kidney Function

The management of patients with impaired kidney function requires comprehensive strategies addressing medication adjustments, fluid and electrolyte balance, blood pressure control, and timely specialist referral to optimize outcomes and prevent disease progression.

Assessment and Monitoring

• Estimate creatinine clearance in all patients with kidney dysfunction to guide medication dosing and adjustments 1
• Monitor kidney function regularly through serum creatinine, estimated glomerular filtration rate (eGFR), and assessment of proteinuria/albuminuria 1
• Calculate contrast volume to creatinine clearance ratio before procedures requiring contrast media to minimize risk of contrast-induced nephropathy 1
• Assess for risk factors that may worsen kidney function, including diabetes mellitus, hypertension, proteinuria, older age, and smoking 1

Medication Management

Renin-Angiotensin System Inhibitors

• Use ACE inhibitors or ARBs as first-line therapy for patients with both hypertension and proteinuria 1
• Do not stop ACEi or ARB with modest and stable increases in serum creatinine (up to 30%) 1
• Stop ACEi or ARB if kidney function continues to worsen or if refractory hyperkalemia develops 1, 2
• Consider starting at lower doses in patients with advanced CKD and titrating up based on tolerance 2
• Monitor serum potassium and creatinine 1-2 weeks after initiating ACEi/ARB therapy 1, 2
• Counsel patients to temporarily hold ACEi/ARB and diuretics during periods of volume depletion (e.g., illness with vomiting/diarrhea) 1

Medication Dose Adjustments

• Adjust doses of renally cleared medications according to estimated creatinine clearance 1
• For patients with mild-to-moderate hepatic impairment, start losartan at 25 mg 2
• For patients on dialysis receiving tyrosine kinase inhibitors (TKIs), consider starting at lower than standard doses and titrating up based on tolerability 1

Fluid and Electrolyte Management

Fluid Balance

• Recommend daily fluid intake of 1.5-2 liters for most patients with CKD, except in edematous states 3
• Provide adequate preparatory hydration for patients undergoing procedures with contrast media 1
• Monitor weight and volume status regularly in hospitalized patients with CKD 3
• Avoid overhydration in patients receiving TKIs due to their large distribution volume 1

Sodium Management

• Restrict dietary sodium to <2.0 g/d (<90 mmol/d) for all patients with kidney disease 1
• Intensify dietary sodium restriction in patients who fail to achieve proteinuria reduction despite maximal medical therapy 1

Diuretic Therapy for Volume Overload

• Use loop diuretics as first-line therapy for edema management, preferring twice daily dosing 1
• Increase loop diuretic dose until clinically significant diuresis is achieved or maximum effective dose is reached 1
• Consider switching to longer-acting loop diuretics (bumetanide, torsemide) if concerned about oral bioavailability 1
• For resistant edema, combine loop diuretics with thiazide-like diuretics for synergistic effect 1, 3
• Monitor for adverse effects of diuretics: hypokalemia, hyponatremia, impaired GFR, and volume depletion 1

Potassium Management

• Recommend low-potassium diet with GFR less than 20 ml/min or less than 50 ml/min if taking medications that raise serum potassium 3
• Monitor serum potassium periodically, especially in patients on ACEi/ARB therapy 2
• Use potassium-wasting diuretics and/or potassium-binding agents to maintain normal potassium levels when using RAS blockers 1
• For hyperkalemia without symptoms or ECG changes, review medications, restrict dietary potassium, and consider oral ion exchange resins 3
• For symptomatic hyperkalemia, use standard parenteral treatments (calcium gluconate, insulin/glucose, salbutamol) 3

Acid-Base Balance

• Treat metabolic acidosis with oral sodium bicarbonate (0.5-1 mEq/kg/day) to achieve serum bicarbonate levels of 22-24 mmol/L 3
• Limit daily protein intake to less than 1 g/kg/day to help manage metabolic acidosis 3
• Monitor and correct acidosis in patients using sevelamer as a phosphate binder 3

Blood Pressure Management

• Target systolic blood pressure <120 mm Hg in most adult patients using standardized office BP measurement 1
• In practice, aim for SBP of 120-130 mm Hg in most patients with glomerular disease 1
• Employ lifestyle modifications (sodium restriction, weight normalization, smoking cessation, regular exercise) as synergistic means for improving control of hypertension and proteinuria 1

Cardiovascular Risk Management

• Consider statin therapy as first-line treatment for persistent hyperlipidemia in patients with kidney disease, particularly those with other cardiovascular risk factors 1
• Assess atherosclerotic cardiovascular disease risk based on LDL-C, Apo B, triglyceride and Lp(a) levels, age group, and risk enhancers 1
• Consider non-statin therapy for those who cannot tolerate statins or fail to achieve lipid goals despite maximal statin dose 1

Specialist Referral

• Refer patients to nephrology specialists when the cause of CKD is uncertain, for hereditary kidney disease, or with recurrent nephrolithiasis 1
• Refer when eGFR <30 mL/min per 1.73 m², or with a sustained fall in GFR of >20% or >30% after starting hemodynamically active therapies 1
• Consider referral when there is a >3-5% 5-year risk of requiring kidney replacement therapy 1
• For patients with advanced CKD, consider non-traditional modes of nephrology care delivery such as e-consults and tele-nephrology 1

Special Considerations for Cancer Patients with Kidney Dysfunction

• Collaborate between nephrology and oncology specialists for optimal management of patients with both conditions 1
• For patients with kidney disease receiving TKIs, start at lower doses and titrate up based on tolerability 1
• Monitor for immune checkpoint inhibitor-associated nephritis, which typically resolves with drug discontinuation and steroid therapy 1
• Conduct kidney function evaluations in all hematology/oncology patients, including estimating GFR and determining the degree of proteinuria 1

Lifestyle Modifications

• Recommend individualized and balanced diets high in vegetables, fruits, and whole grains but low in refined carbohydrates 1
• Target dietary protein intake of 0.8 g/kg/day for most patients with CKD 1
• Advise moderate to intense physical activity with cumulative duration of ≥150 min/week 1
• Encourage achieving and maintaining healthy weight through diet, physical activity, and behavioral therapy 1
• Strongly advise smoking cessation 1