What is the treatment for Acute Kidney Injury (AKI) in patients with Chronic Kidney Disease (CKD)?

From the Guidelines

Treatment of acute kidney injury (AKI) in patients with chronic kidney disease (CKD) should prioritize prompt identification and management of the underlying cause, discontinuation of nephrotoxic medications, and optimization of volume status. The first step is to identify and treat reversible causes such as volume depletion, nephrotoxic medications, urinary obstruction, or infection 1. Discontinue potentially nephrotoxic drugs including NSAIDs, certain antibiotics (aminoglycosides, vancomycin), and contrast agents. Optimize volume status with careful fluid management—administer isotonic fluids like normal saline if hypovolemic, but avoid fluid overload which can worsen kidney function.

Key Considerations

• Blood pressure should be controlled to prevent further kidney damage, typically aiming for <140/90 mmHg using ACE inhibitors or ARBs if appropriate 1.
• Electrolyte abnormalities, particularly hyperkalemia, should be monitored and treated promptly with insulin/glucose, sodium bicarbonate, calcium gluconate, or potassium binders like patiromer or sodium zirconium cyclosilicate if severe.
• Metabolic acidosis may require sodium bicarbonate supplementation.
• Nutritional support should be optimized with protein intake of 0.8-1.0 g/kg/day.
• Renal replacement therapy (dialysis) should be considered for severe cases with refractory hyperkalemia, volume overload, uremic symptoms, or severe acidosis.

Recent Guidelines

According to the most recent guidelines, when AKI is diagnosed, diuretics and nonselective beta-blockers should be held, NSAIDs discontinued, the precipitating cause of AKI treated, and fluid losses replaced, administering albumin 1 g/kg/d for 2 days if the serum creatinine shows doubling from baseline 1. Urine output, vital signs, and when indicated, echocardiography or CVP (if there is a pre-existing central line) should be used to monitor fluid status. The goal is to prevent further kidney damage and improve outcomes in patients with AKI and CKD.

From the Research

Treatment of Acute Kidney Injury (AKI) in Chronic Kidney Disease (CKD)

• The treatment of AKI is founded on addressing the underlying cause, as well as providing supportive care through fluid management, vasopressor therapy, and kidney replacement therapy (KRT) 2.
• Loop diuretics, such as furosemide, are commonly used in the management of AKI complications, including volume overload and electrolyte management 3.
• The furosemide stress test has been shown to predict the need for renal replacement therapy and identify AKI patients at higher risk of progression 3, 4.

AKI as a Risk Factor for CKD Development and Progression

• AKI is recognized as a risk factor for CKD development and progression to end-stage renal disease (ESRD) 5.
• The pathophysiology of AKI to CKD transition involves maladaptive repair, cell death, endothelial dysfunction, and inflammatory processes, which can lead to fibrosis 5.

Treatment Options for CKD

• Treatment of metabolic acidosis with sodium bicarbonate has been shown to delay the progression of CKD and improve kidney and patient survival 6.
• The use of sodium bicarbonate in patients with CKD stage 3-5 has been found to be safe and effective in improving outcomes 6.

Predicting the Need for Continuous Renal Replacement Therapy (CRRT)

• The furosemide stress test can be used to predict the timing of CRRT initiation in critically ill patients with AKI 4.
• FST non-responders are more likely to require CRRT, and the test can be used to identify high-risk patients 4.