What is the treatment approach for Acute Kidney Injury (AKI)?

Treatment Approach for Acute Kidney Injury (AKI)

The first priority in treating AKI is to identify and treat the underlying cause while immediately discontinuing all nephrotoxic medications, including NSAIDs, aminoglycosides, and iodinated contrast media. 1

Initial Management

• Review all medications (including over-the-counter drugs) and withdraw diuretics, nephrotoxic drugs, vasodilators, and NSAIDs 2
• Discontinue beta-blockers when AKI is diagnosed to prevent further kidney injury 1
• Perform plasma volume expansion in patients with clinically suspected hypovolemia using crystalloids as first-line fluid therapy 2
• For patients with cirrhosis and ascites with AKI, administer intravenous albumin at 1 g/kg bodyweight for two consecutive days 2, 1
• Target mean arterial pressure of at least 65 mmHg to ensure adequate renal perfusion in prerenal AKI 1

Management Based on AKI Stage

Stage 1 AKI:

• Close monitoring of renal function and urine output 2
• Remove risk factors (nephrotoxic drugs, vasodilators, NSAIDs) 2
• Decrease or withdraw diuretics 2
• Treat underlying infections when diagnosed 2
• Plasma volume expansion for hypovolemia 2

Stage 2-3 AKI:

• All interventions for Stage 1, plus:
• Consider vasopressor therapy if fluid resuscitation fails to restore adequate blood pressure 1
• For hepatorenal syndrome AKI (HRS-AKI), administer vasoactive agents (terlipressin, norepinephrine, or midodrine plus octreotide) along with albumin 1

Fluid Management

• Use isotonic crystalloids rather than colloids as initial management for volume expansion 2
• Avoid hydroxyethyl starches due to increased risk of AKI 2
• Consider albumin in specific subgroups: patients with expected high fluid volume needs, severe hypoalbuminemia, or cirrhosis with spontaneous bacterial peritonitis 2
• Monitor for fluid overload using urine output, vital signs, and when indicated, echocardiography 1

Medication Management

• Diuretics should not be used to prevent or treat AKI except for managing volume overload 3
• Avoid the "triple whammy" combination of NSAIDs, diuretics, and ACE inhibitors/ARBs, which significantly increases AKI risk 1
• Each additional nephrotoxin increases the odds of developing AKI by 53% 1, 3
• Avoid NSAIDs in elderly patients with creatinine clearance <30 ml/min 1

Renal Replacement Therapy (RRT) Indications

• Individualize timing of RRT based on the patient's overall clinical condition 1
• Consider RRT for refractory hyperkalemia, volume overload, intractable acidosis, uremic encephalopathy, pericarditis, or pleuritis 4

Monitoring and Follow-up

• For patients with persistent AKI (>48 hours), reassess the etiology and consider nephrology consultation 2
• Monitor electrolytes every 12-24 hours during acute management 3
• Timed urine creatinine clearance is currently the best available estimate of kidney function for patients with persistent AKI in the steady state 2
• Note that eGFR equations (MDRD, CKD-EPI) are not accurate for assessment of renal function in persistent AKI 2

Prevention of AKI Progression

• Continue nephrotoxin avoidance during the recovery phase to prevent re-injury 1
• Recognize that AKI is not self-limited but strongly linked to increased risk for chronic kidney disease, subsequent AKI, and future mortality 5
• Consider clinical follow-up after AKI, particularly for patients with severe AKI (requiring temporary RRT) or persisting renal dysfunction at hospital discharge 2

Common Pitfalls to Avoid

• Using furosemide in hemodynamically unstable patients with AKI can precipitate volume depletion and further renal hypoperfusion 3
• Using eGFR equations designed for CKD to assess renal function in AKI 2
• Combining multiple nephrotoxic medications 1, 3