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

Treatment Approach for Acute Kidney Injury (AKI)

The management of acute kidney injury requires immediate identification and treatment of the underlying cause, removal of nephrotoxic medications, optimization of fluid status, and consideration of renal replacement therapy in severe cases. 1

Initial Management

• Identify and treat the underlying cause of AKI as the first priority 1
• Evaluate nephrotoxins as a potential cause or contributor to AKI through assessment of temporal sequence, other possible causes, and response to drug removal 1
• Discontinue nephrotoxic medications including NSAIDs, aminoglycosides, and iodinated contrast media 1
• Hold diuretics and beta-blockers when AKI is diagnosed to prevent further kidney injury 1
• Review all medications including over-the-counter drugs that may contribute to kidney injury 1

Fluid Management

• Assess volume status and provide appropriate fluid resuscitation for hypovolemic patients using crystalloids rather than colloids 2
• Administer intravenous albumin at a dose of 1 g/kg/day for two consecutive days in patients with significant AKI (doubling of serum creatinine) 1
• Monitor for fluid overload which can worsen outcomes in AKI; use urine output, vital signs, and when indicated, echocardiography or CVP to guide therapy 1, 2
• Transition to neutral or negative fluid balance once hemodynamic stability is achieved to prevent complications of fluid overload 2

Specific Management Based on AKI Type

Prerenal AKI

• Optimize hemodynamics with fluid resuscitation and vasopressors if needed 1
• Target mean arterial pressure of at least 65 mmHg to ensure adequate renal perfusion 1
• Consider vasopressor therapy if fluid resuscitation fails to restore adequate blood pressure 1

Hepatorenal Syndrome AKI (HRS-AKI)

• Administer vasoactive agents (terlipressin, norepinephrine, or midodrine plus octreotide) along with albumin when serum creatinine remains elevated despite initial management 1
• Continue therapy until serum creatinine returns to within 0.3 mg/dL of baseline for 2 consecutive days or for a maximum of 14 days 1
• Monitor for ischemic side effects of vasoconstrictors including angina and ischemia of fingers, skin, and intestine 1

Intrinsic AKI

• Treat specific causes such as glomerulonephritis, vasculitis, or interstitial nephritis with appropriate therapy 3
• Consider renal biopsy in selected cases where the cause remains unclear despite thorough evaluation 3

Prevention of Nephrotoxicity

• Avoid combinations of nephrotoxic drugs as each additional nephrotoxin increases the odds of developing AKI by 53% 1
• Be particularly cautious with the "triple whammy" of NSAIDs, diuretics, and ACE inhibitors or ARBs which significantly increases AKI risk 1
• Avoid NSAIDs in elderly patients with creatinine clearance <30 ml/min 1
• Adjust medication dosages according to kidney function to prevent toxicity 4

Indications for Renal Replacement Therapy

• Initiate renal replacement therapy for refractory hyperkalemia, volume overload, intractable acidosis, uremic encephalopathy, pericarditis, or pleuritis 3
• Consider earlier initiation of RRT when using conservative fluid management strategies 2
• Individualize timing of RRT based on the overall clinical condition rather than specific creatinine or BUN thresholds 1, 4

Management of Complications

• Monitor and correct electrolyte imbalances, particularly hyperkalemia 3
• Consider potassium-binding resins for hyperkalemia, administered at least 3 hours before or after other oral medications 5
• Manage metabolic acidosis with sodium bicarbonate in selected cases 1
• Adjust medication dosing based on the degree of kidney dysfunction 4

Follow-up and Monitoring

• Continue nephrotoxin avoidance during the recovery phase of AKD to prevent re-injury 1
• Monitor for transition to chronic kidney disease, as AKI is a significant risk factor for CKD development 4
• Educate patients to avoid taking NSAIDs or new medications without consulting their healthcare provider 1

By following this systematic approach to AKI management, focusing on treating the underlying cause, optimizing fluid status, avoiding nephrotoxins, and providing appropriate supportive care, outcomes can be improved in this high-risk condition.