What is the immediate management approach for patients requiring emergent dialysis?

Immediate Management of Patients Requiring Emergent Dialysis

For patients requiring emergent dialysis, immediate vascular access should be established with an uncuffed non-tunneled dialysis catheter of appropriate length and gauge, followed by prompt initiation of continuous renal replacement therapy (CRRT) for hemodynamically unstable patients or intermittent hemodialysis for stable patients. 1

Initial Assessment and Access Placement

Vascular Access

• Establish immediate vascular access using an uncuffed non-tunneled dialysis catheter 1
• For patients with acute kidney injury (AKI) requiring emergent dialysis, central venous access is preferred
• Avoid peripherally inserted catheters in patients with CKD stages 3-5 to preserve vessels for potential future permanent access 1

Hemodynamic Assessment

• Determine hemodynamic stability to guide modality selection:
  • Unstable patients (hypotension, shock): CRRT is preferred
  • Stable patients: Intermittent hemodialysis can be used
• If dialysis is indicated urgently while resolving conflicts about treatment decisions, it should be provided while pursuing conflict resolution 1

Modality Selection Algorithm

For Hemodynamically Unstable Patients:

1. First choice: CRRT (CVVH or CVVHDF) 1

   • Provides better hemodynamic stability
   • Avoids major fluid or osmotic shifts
   • Reduces risk of worsening intracranial pressure
   • Dosing: 25-30 units/kg heparin followed by infusion of 1,500-2,000 units/hour 2

2. Second choice: Peritoneal Dialysis (PD) if CRRT unavailable 1

   • Does not require vascular access
   • Does not require systemic anticoagulation
   • Use rigid peritoneal catheters only if no alternatives exist 1
   • Can be initiated immediately under experienced personnel 1

For Hemodynamically Stable Patients:

1. Intermittent Hemodialysis
   • More efficient for rapid solute removal
   • Shorter treatment time (3-4 hours)
   • Higher blood flow rates

Special Considerations

Timing of Dialysis in Specific Scenarios

• Acute Coronary Syndrome: Timing of dialysis in first 48 hours should consider volume status, electrolyte disturbances, and bleeding risk 1
• Hyperammonemia: CRRT preferred over intermittent HD due to reduced risk of rebound hyperammonemia 1

Anticoagulation

• For CRRT, standard heparin dosing: 25-30 units/kg loading dose followed by 1,500-2,000 units/hour infusion 2
• Consider reduced or no anticoagulation in patients with bleeding risk
• For patients with heparin contraindications, consider regional citrate anticoagulation

Post-Initiation Management

Establish ESKD Life-Plan

• Within 30 days of urgent dialysis start with a CVC, establish an ESKD Life-Plan with a permanent dialysis access plan 1
• For patients who will continue on hemodialysis, plan for AV access creation
• For patients choosing PD, plan for PD catheter placement at least 2 weeks before anticipated need 1

Monitoring and Adjustment

• Monitor for:
  • Hemodynamic stability
  • Electrolyte abnormalities (particularly potassium)
  • Acid-base status
  • Signs of bleeding (if anticoagulated)
  • Catheter function and signs of infection

Common Pitfalls to Avoid

• Delaying dialysis when urgently indicated due to concerns about vascular access
• Using estimated GFR alone to determine dialysis initiation timing 3, 4
• Failing to consider palliative care options for patients with poor prognosis 1
• Inadequate anticoagulation leading to circuit clotting in CRRT
• Overly aggressive ultrafiltration causing hemodynamic instability

Long-term Planning

• After stabilization, transition from emergent to maintenance dialysis
• Consider time-limited trials of dialysis for patients with uncertain prognosis 1
• Refer for permanent access creation (AV fistula/graft) within 30 days for patients continuing hemodialysis 1
• Discuss advance directives with all dialysis patients 1

The mortality risk for patients requiring emergent dialysis is substantial, with studies showing approximately 75% mortality at 2 years after acute events like myocardial infarction in dialysis patients 1. This underscores the importance of prompt, appropriate intervention and careful long-term planning.