When is dialysis indicated for patients with impaired renal function, such as end-stage renal disease (ESRD) or acute kidney injury (AKI)?

Dialysis Indication in Renal Failure

Dialysis should be initiated when patients develop uremic symptoms (serositis, pruritus, cognitive impairment), life-threatening complications (severe hyperkalemia, refractory metabolic acidosis, volume overload unresponsive to diuretics), or progressive nutritional deterioration despite dietary intervention, which typically occurs when GFR falls to 5-10 mL/min/1.73 m² but should not be based on GFR alone. 1

Absolute Indications for Dialysis

The following are life-threatening conditions requiring immediate dialysis initiation:

• Severe hyperkalemia causing cardiac arrhythmias or ECG changes unresponsive to medical management 2
• Refractory metabolic acidosis that cannot be corrected with bicarbonate therapy 2
• Uremic complications including pericarditis (uremic serositis), encephalopathy, or bleeding diathesis 1, 2
• Refractory volume overload causing pulmonary edema or compromising cardiac function despite maximal diuretic therapy 1, 2

Clinical Symptoms and Signs Warranting Dialysis

Beyond laboratory values, specific clinical manifestations indicate dialysis need:

• Uremic symptoms: Intractable nausea/vomiting, pruritus, altered mental status, asterixis 1
• Serositis: Pericarditis or pleuritis attributable to uremia 1
• Progressive nutritional deterioration refractory to dietary intervention, manifested by declining serum albumin, decreasing edema-free body weight, or deteriorating subjective global assessment 1

GFR-Based Considerations for Chronic Kidney Disease

While GFR alone should not dictate dialysis timing, it provides important context:

• GFR < 15 mL/min/1.73 m² defines kidney failure, and approximately 98% of U.S. patients begin dialysis at this threshold 1
• Weekly Kt/V < 2.0 (approximating kidney urea clearance of 7 mL/min) suggests dialysis consideration unless patients meet specific exceptions 1
• Exceptions to initiating dialysis despite low GFR include: stable or increasing edema-free body weight, adequate nutritional markers (serum albumin above laboratory lower limit and stable/rising), and complete absence of uremic symptoms 1

Special Populations and Modality Selection

Acute Kidney Injury (AKI)

For critically ill patients with AKI, modality selection depends on hemodynamic stability:

• Hemodynamically stable patients: Intermittent hemodialysis (3-4 hours, 3 times weekly) is acceptable 3, 2
• Hemodynamically unstable patients (particularly those with severe coronary artery disease): Continuous renal replacement therapy (CRRT) or prolonged intermittent renal replacement therapy (PIRRT) are preferred due to superior hemodynamic stability and slower solute shifts 3, 2

End-Stage Renal Disease (ESRD)

• Standard treatment: Conventional intermittent hemodialysis (3 times weekly, 3-4 hours per session) for stable ESRD patients 3
• Preemptive transplantation: Should be considered when GFR < 20 mL/min/1.73 m² with evidence of progressive, irreversible CKD over 6-12 months 1

Predictors of Earlier Dialysis Need

Certain predialysis characteristics predict patients who will require dialysis at higher GFR levels (≥7.8 mL/min/1.73 m²):

• Heart failure (strongest predictor with adjusted OR 3.68) 4
• Serum albumin < 4.0 g/dL (OR 2.22) 4
• BUN/Creatinine ratio > 15 mg/mg (OR 1.92) 4
• Hyperuricemia (OR 1.84) 4

These patients require earlier vascular access planning and predialysis counseling 4.

Critical Pitfalls to Avoid

• Do not delay dialysis in patients with absolute indications while attempting hemodynamic optimization, as this increases mortality 2
• Avoid standard intermittent hemodialysis in hemodynamically unstable patients, particularly those with coronary artery disease, as rapid fluid shifts can precipitate cardiac ischemia or arrhythmias 2
• Do not rely solely on BUN levels (e.g., BUN > 75 mg/dL) as the sole indicator for asymptomatic patients, as this is based on limited evidence 5
• Avoid initiating dialysis based on eGFR alone without considering clinical trajectory, symptoms, and nutritional status 1, 5

Conservative Management Option

For patients who decline renal replacement therapy, comprehensive conservative management should be offered, including:

• Advance care planning and end-of-life discussions 1
• Symptom and pain management protocols 1
• Psychological, spiritual, and culturally sensitive care 1