What are the indications for Hemodialysis (HD)?

Indications for Hemodialysis

Hemodialysis should be initiated based on clinical symptoms and signs of uremia rather than GFR alone, with absolute indications including uremic pericarditis, encephalopathy, intractable nausea/vomiting, bleeding diathesis, refractory volume overload, severe hyperkalemia unresponsive to medical therapy, and severe metabolic acidosis. 1

When NOT to Start Dialysis

• Do not initiate dialysis based solely on estimated GFR, even when it falls below traditional thresholds 1, 2
• In asymptomatic patients with stage 5 CKD, dialysis may be safely delayed until eGFR is 5-7 mL/min/1.73 m² with careful clinical follow-up 2
• Early dialysis initiation (eGFR >10 mL/min/1.73 m²) provides no survival benefit and may cause harm 1, 2
• For patients with residual kidney function, consider that weekly renal Kt/V below 2.0 (approximating renal urea clearance of 7 mL/min) may indicate need for dialysis, but only if accompanied by uremic symptoms 3

Absolute Indications for Dialysis Initiation

Uremic Symptoms

• Uremic pericarditis - an absolute emergency indication 1
• Uremic encephalopathy with altered mental status or seizures 1
• Intractable nausea and vomiting refractory to antiemetics 1
• Uremic bleeding diathesis with clinical bleeding 1

Volume and Hemodynamic Complications

• Refractory volume overload unresponsive to diuretic therapy 1
• Uncontrolled hypertension despite maximal medical management 1
• Severe pulmonary edema threatening respiratory failure 4

Metabolic Derangements

• Hyperkalemia unresponsive to medical therapy (typically >6.5-7.0 mEq/L with ECG changes) 1, 4
• Severe metabolic acidosis (typically pH <7.1 or bicarbonate <10 mEq/L) refractory to bicarbonate therapy 1

Nutritional Failure

• Protein-energy malnutrition that develops or persists despite vigorous nutritional intervention 1
• For peritoneal dialysis patients, severe malnutrition resistant to aggressive management warrants transfer to hemodialysis 3

Relative Indications Requiring Clinical Judgment

• GFR <15 mL/min/1.73 m² in pediatric patients, though this should follow adult guidelines 3
• Progressive decline in nutritional status with stable or decreased edema-free body weight, low serum albumin, or declining lean body mass 3
• Inadequate solute clearance when maximum peritoneal dialysis prescription has been reached or lifestyle complications prevent adequate PD 3
• Unacceptably frequent peritonitis in PD patients (definition individualized per patient and facility availability) 3

Critical First Steps Before Initiating Dialysis

Verify True Renal Function

• Obtain measured GFR using 24-hour urine collection for creatinine and urea clearance rather than relying on estimated GFR 1
• Creatinine-based eGFR formulas are inaccurate in ESRD patients and should not solely guide dialysis initiation 2, 5
• The MDRD equation overestimates GFR at low levels; when measured GFR is 15 mL/min/1.73 m², MDRD may read 19.7 mL/min/1.73 m² 5

Ensure Adequate Dialysis Access

• Planned elective dialysis start (with access created well in advance) reduces mortality and hospitalization risk compared to urgent or unplanned starts 6
• Patients with planned elective access creation at mean eGFR 5.3 mL/min/1.73 m² showed lowest rates of mortality and hospitalization over 2 years 6

Initial Dialysis Protocol

First Session Approach

• Use "low and slow" approach to minimize dialysis disequilibrium syndrome and hemodynamic instability 1
• Initial session duration: 2-2.5 hours with reduced blood flow rates of 200-250 mL/min 1
• Minimal ultrafiltration during first session 1
• Monitor vital signs every 15-30 minutes with close observation for neurological symptoms 1
• Gradual dose escalation over subsequent sessions as tolerated 1

Dialysis Prescription Targets

• Minimum delivered Kt/V should be 1.2 per dialysis session for patients dialyzed 3 times weekly 3
• Prescribed Kt/V should be 1.4 to ensure delivered dose doesn't fall below 1.2 (accounting for coefficient of variation of 0.1) 3
• This corresponds to URR of approximately 70%, though URR varies with ultrafiltration 3
• Measure delivered dose monthly in all patients to ensure adequacy 3

Frequency Considerations

• Three times weekly is standard for patients without significant residual kidney function 3
• Twice-weekly hemodialysis is inadequate unless residual GFR ≥5 mL/min, and residual function must be monitored serially 3
• More frequent dialysis (daily or nocturnal) reduces intradialytic hypotension by 20-68% and improves recovery time 7

Special Considerations for Residual Kidney Function

• Residual kidney function (RKF) preservation is critical as it provides continuous clearance and reduces hemodynamic instability 3
• Include RKF in clearance calculations when residual urea clearance >2 mL/min 3
• Measure RKF every 4 months using 24-hour urine collection for urea clearance 3
• Avoid intradialytic hypotension to preserve RKF through strategies including lower dialysate temperature, slower blood flow initiation, and gentle fluid removal 3

Common Pitfalls to Avoid

• Never initiate dialysis based on GFR alone in asymptomatic patients - this provides no survival benefit 1, 2
• Avoid aggressive first dialysis sessions - rapid solute removal causes cerebral edema, seizures, and cardiovascular instability 1
• Hemodialysis-related hypotension accelerates loss of residual kidney function, particularly problematic in patients who may recover renal function 1
• Do not target delivered Kt/V of only 1.2 - prescribe 1.4 to account for variability and ensure minimum dose is consistently achieved 3
• Clinical signs and symptoms alone are unreliable indicators of dialysis adequacy - objective measurement is essential 3