What are the pharmacological and surgical management options for Acute Kidney Injury (AKI) and its complications?

Pharmacological and Surgical Management of Acute Kidney Injury and Its Complications

The management of established AKI is predominantly supportive care, with the use of renal replacement therapy (RRT) in severe cases, as there are no effective pharmacologic therapies that have demonstrated utility in clinical practice for treating most forms of AKI. 1

Prevention and Risk Factor Management

• Implement preventive measures including avoidance of alcohol use, monitoring serum creatinine and electrolytes in patients on diuretics, and avoiding nephrotoxic medications such as NSAIDs, ACE inhibitors, and ARBs in high-risk patients 1
• Administer albumin infusion with therapeutic paracentesis in cirrhotic patients and provide antibiotic prophylaxis against spontaneous bacterial peritonitis to prevent hepatorenal syndrome 1
• Implement drug stewardship programs that include identification of patients at risk for AKI, assessment of hydration status, review of chronic medications, and evaluation of pharmacokinetic/pharmacodynamic interactions 2, 3
• Avoid the "triple whammy" combination of NSAIDs, diuretics, and ACE inhibitors/ARBs, which significantly increases AKI risk 3

Initial Management of Established AKI

• Discontinue all nephrotoxic medications immediately, including ACE inhibitors, ARBs, NSAIDs, and diuretics 1, 3
• Determine and correct volume status:
  • For hypovolemic patients, administer fluid repletion preferably with balanced crystalloid solutions rather than 0.9% saline 2, 3
  • For euvolemic or hypervolemic patients, avoid excessive fluid administration which can worsen outcomes 2, 3
• Consider vasopressors when fluid resuscitation fails to restore renal perfusion, particularly in sepsis 2, 3
• Adjust dosages of all medications based on current estimated GFR and reassess frequently as kidney function changes 2, 3

Pharmacological Management

• For hepatorenal syndrome-AKI, administer vasoconstrictor therapy with albumin when serum creatinine has increased >1.5 mg/dL or to 2 times baseline value despite risk factor management for 2 days 1
• Monitor carefully for fluid overload when administering albumin due to risk of pulmonary edema, especially in patients with cirrhosis 1
• Avoid nephrotoxic agents including intravenous aminoglycosides, amphotericin B, foscarnet, intravenous pentamidine, vancomycin, and NSAIDs in patients with established AKI 4
• There are currently no specific pharmacologic agents approved for treating established AKI itself, as most agents showing promise in experimental models have not demonstrated utility in clinical care 1, 5

Renal Replacement Therapy (RRT)

• Indications for RRT include:

  • Severe oliguria unresponsive to fluid resuscitation
  • Severe metabolic derangements (acidosis, hyperkalemia)
  • Uremic symptoms
  • Fluid overload refractory to diuretics 2, 3

• Available RRT modalities:

  • Hemodiálisis intermitente (HDI): Suitable for hemodynamically stable patients requiring rapid toxin removal 2, 3
  • Continuous renal replacement therapies (CRRT): Indicated for hemodynamically unstable patients, sepsis, or multiorgan failure 2, 3
  • Peritoneal dialysis: Alternative for patients with difficult vascular access or in resource-limited settings 2
  • Hybrid therapies (e.g., SLED - sustained low-efficiency dialysis): Combine benefits of continuous and intermittent modalities 2

• The optimal timing for initiating RRT remains controversial, with recent evidence not consistently demonstrating benefit to early initiation 3, 5

Management of Complications

• Metabolic acidosis: Monitor serum bicarbonate levels and correct acidosis with RRT when severe 2, 4
• Hyperkalemia: Manage with insulin/glucose, calcium gluconate, sodium bicarbonate, potassium binders, or RRT in severe cases 2
• Fluid overload: Implement fluid restriction and consider diuretics or ultrafiltration via RRT 2, 3
• Uremia: Monitor for signs of uremic complications and initiate RRT when clinically indicated 3
• Electrolyte abnormalities: Monitor electrolytes frequently and correct imbalances 2, 3

Follow-up and Long-term Management

• Monitor renal function periodically after an AKI episode as patients remain at increased risk of progressive chronic kidney disease 1, 6
• Evaluate recovery of kidney function (filtration, tubular, endocrine) and structure 2
• Provide patient education regarding medication avoidance, especially over-the-counter NSAIDs, and when to seek medical attention for symptoms of worsening kidney function 3

Common Pitfalls to Avoid

• Delaying RRT when clear indications exist, which increases mortality 3
• Overly aggressive fluid administration in non-hypovolemic patients, worsening outcomes 2, 3
• Inappropriate continuation of nephrotoxic medications during AKI recovery 3
• Failing to identify and address the underlying cause of AKI, leading to continued kidney damage 3
• Overly rapid correction of hyponatremia, which can lead to osmotic demyelination syndrome 3