What are the indications for dialysis in patients with impaired renal function, particularly older adults with a history of diabetes, hypertension, or other kidney diseases?

Indications for Dialysis in Patients with Impaired Renal Function

Dialysis should be initiated based on clinical symptoms and life-threatening complications of kidney failure rather than GFR alone, with absolute indications including uremic complications (pericarditis, encephalopathy, seizures, neuropathy), refractory hyperkalemia >6.0 mmol/L, severe metabolic acidosis unresponsive to medical therapy, and volume overload refractory to diuretics. 1, 2

Absolute (Emergent) Indications

These require immediate dialysis initiation regardless of GFR:

• Uremic complications including pericarditis, encephalopathy, seizures, or uremic neuropathy mandate urgent dialysis 1, 2
• Life-threatening hyperkalemia (>6.0 mmol/L) or persistent hyperkalemia unresponsive to medical therapy (insulin/glucose, calcium gluconate, sodium bicarbonate) 2
• Moderate hyperkalemia (5.3-6.0 mmol/L) accompanied by ECG changes or uremic symptoms 2
• Refractory volume overload unresponsive to aggressive diuretic therapy 1, 2
• Severe metabolic acidosis that cannot be controlled with medical management 1, 2
• Serositis (pericarditis or pleuritis) 1

Relative (Urgent) Indications

These typically warrant dialysis within 24-48 hours:

• Refractory pruritus despite medical management 1
• Progressive deterioration in nutritional status despite dietary intervention 1
• Cognitive impairment attributable to uremia 1
• Inability to control blood pressure despite optimal medical therapy 1
• Progressive hyperphosphatemia (>6 mg/dL) with risk of calcium-phosphate precipitation 1, 2

GFR-Based Considerations

While symptoms drive the decision, GFR provides context:

• GFR 5-10 mL/min/1.73 m²: This range typically correlates with uremic symptom development, but timing must be individualized based on symptom burden rather than the number itself 1
• GFR <15 mL/min/1.73 m²: Defined as kidney failure, with 98% of US patients beginning dialysis below this threshold 1
• GFR <20 mL/min/1.73 m²: Consider preemptive living donor kidney transplantation for patients with progressive, irreversible CKD over 6-12 months 1

Special Considerations for Older Adults with Diabetes and Hypertension

For older adults with diabetes and hypertension, dialysis initiation requires careful consideration of competing mortality risks and quality of life, as these patients face higher burdens from dialysis with potentially limited survival benefit. 1

• Conservative management with comprehensive palliative care represents a reasonable alternative for older adults with limited life expectancy or those wishing to avoid medical interventions 1, 3
• The decision should involve shared decision-making that weighs potential benefits against treatment burdens 3
• Baseline renal function, prior AKI episodes, and presence of congestive heart failure predict outcomes and should inform the decision 4, 5

Critical Pitfalls to Avoid

• Do not initiate dialysis based solely on GFR thresholds without clinical symptoms—this approach may expose patients to unnecessary risks without mortality benefit 1
• Do not treat asymptomatic hypocalcemia that commonly accompanies hyperphosphatemia, as calcium supplementation worsens calcium-phosphate precipitation in tissues 2
• Only treat symptomatic hypocalcemia (tetany, seizures) with cautious calcium gluconate administration 2
• Preserve peripheral veins in patients with stage III-V CKD by avoiding unnecessary venipunctures and peripheral IV placement, as most patients will require hemodialysis access 1, 3
• Recognize that initiating dialysis at lower creatinine levels (<3.8 mg/dL) may be associated with increased mortality rather than benefit 6

Pre-Dialysis Preparation

Once dialysis appears likely (GFR <20 mL/min/1.73 m²):

• Manage patients in a multidisciplinary setting with access to dietary counseling, education about renal replacement therapy modalities (hemodialysis, peritoneal dialysis, transplantation), vascular access planning and placement, and psychological/social support 1
• Plan vascular access early to allow maturation before dialysis initiation 1
• Ensure vaccination against seasonal influenza, tetanus, hepatitis B, HPV (through age 26), and Streptococcus pneumoniae 3

Dialysis Modality Selection for Acute Situations

• Intermittent hemodialysis (IHD) should be the initial modality for most patients requiring rapid solute and electrolyte removal, providing superior efficiency for removing uric acid, urea, potassium, and phosphate 2
• Continuous renal replacement therapy (CRRT) should be reserved for hemodynamically unstable patients, providing better control of azotemia and fluid overload 2
• Frequent (daily) dialysis is recommended when there is continuous release of metabolites and electrolytes, such as in tumor lysis syndrome 2, 7