What are the immediate management steps for a patient with suspected Acute Kidney Injury (AKI)?

Immediate Management of Acute Kidney Injury (AKI)

The immediate management of suspected AKI should focus on discontinuing nephrotoxic medications, ensuring adequate hydration with isotonic crystalloids, and daily monitoring of kidney function while addressing the underlying cause. 1

Initial Assessment and Management

1. Identify and address the underlying cause:

   • Discontinue nephrotoxic medications immediately:
     • NSAIDs, aminoglycosides, iodinated contrast agents, amphotericin B 1
     • Temporarily hold ACE inhibitors/ARBs, diuretics, and beta-blockers in appropriate cases 1

2. Volume status assessment and correction:

   • For hypovolemic patients: Administer isotonic crystalloids (normal saline or balanced solutions)
   • Initial bolus of 500-1000 mL, then reassess 1
   • For patients with cirrhosis and ascites: Consider albumin 1 g/kg/day (maximum 100g) for two consecutive days 1
   • Target neutral to negative fluid balance after initial resuscitation 1
   • Avoid rapid fluid removal (>1.5-2 L/day) to prevent hemodynamic instability 1

3. Hemodynamic optimization:

   • Maintain adequate blood pressure using vasopressors if necessary in vasomotor shock 2
   • Avoid low-dose dopamine as it is not effective for AKI prevention or treatment 1

Monitoring Parameters

• Daily monitoring of:

  • Serum creatinine and BUN
  • Electrolytes
  • Fluid balance
  • Daily weights
  • Hemodynamic parameters
  • Acid-base status 1

• Use KDIGO criteria to stage AKI severity:

  Stage	Serum Creatinine	Urine Output
  1	Increase ≥0.3 mg/dL within 48h or 1.5-1.9× baseline	<0.5 mL/kg/h for 6-12h
  2	2.0-2.9× baseline	<0.5 mL/kg/h for ≥12h
  3	≥3.0× baseline or ≥4.0 mg/dL or RRT initiation	<0.3 mL/kg/h for ≥24h or anuria for ≥12h

Nephrology Consultation

• Immediate nephrology consultation for:
  • All Stage 3 AKI patients
  • Stage 2 AKI with multiple comorbidities
  • AKI in patients with pre-existing Stage 4-5 CKD 1
  • Patients with severe metabolic acidosis, hyperkalemia, volume overload unresponsive to diuretics, or uremic symptoms 1

Nutritional Support

• Provide 20-30 kcal/kg/day total energy intake
• Protein intake:
  • 0.8-1.0 g/kg/day for non-catabolic AKI patients without dialysis
  • 1.0-1.5 g/kg/day for patients on RRT
• Preferentially use enteral route for nutrition 1

Renal Replacement Therapy (RRT) Considerations

• Consider RRT when:
  • Severe metabolic acidosis
  • Hyperkalemia
  • Volume overload unresponsive to diuretics
  • Uremic symptoms 1
• CRRT is preferred in hemodynamically unstable patients
• IHD can be used in stable patients 1

Common Pitfalls to Avoid

1. Medication errors:

   • Using diuretics to treat AKI outside of volume overload management 1
   • Continuing nephrotoxic medications 1
   • Inappropriate use of "renal-dose" dopamine (ineffective and potentially harmful) 3

2. Management errors:

   • Delayed nephrology consultation (associated with increased mortality) 1
   • Inadequate fluid resuscitation or excessive fluid administration 1
   • Using hydroxyethyl starch solutions (associated with higher risk for RRT and mortality) 2

3. Follow-up errors:

   • Inadequate post-discharge monitoring 1
   • Failure to recognize that even one episode of AKI increases risk of cardiovascular disease, chronic kidney disease, and death 1

Follow-up Care

• Schedule follow-up based on AKI severity:
  • Stage 3 or required RRT: Nephrology follow-up within 1 week of discharge
  • Persistent kidney dysfunction at discharge: Nephrology follow-up within 30 days
  • Stage 2 AKI with recovery: Primary care follow-up within 30 days with kidney function testing
  • Stage 1 AKI with comorbidities: Primary care follow-up within 30-90 days 1

Remember that early intervention with this comprehensive approach is critical, as AKI represents a critical period of vulnerability that can significantly impact morbidity, mortality, and progression to chronic kidney disease 4.