Primary Treatment for Acute Kidney Injury (AKI)
The primary treatment for Acute Kidney Injury (AKI) is identifying and treating the underlying cause, including discontinuation of nephrotoxic medications when possible, while optimizing hemodynamics with appropriate fluid management. 1, 2
Initial Management
- Administer isotonic crystalloids rather than colloids for initial expansion of intravascular volume in patients with or at risk for AKI 1, 2
- Use balanced crystalloids rather than 0.9% saline when possible, as evidence shows better outcomes with physiological crystalloids 2
- Implement protocol-based management of hemodynamic and oxygenation parameters in high-risk patients, particularly in perioperative settings or in patients with septic shock 1, 2
- Administer vasopressors in conjunction with fluids in patients with vasomotor shock with or at risk for AKI 1
- Monitor fluid status closely to avoid pulmonary edema with excessive fluid administration, as fluid overload can worsen kidney function and delay recovery 1, 3, 4
- Discontinue nephrotoxic medications when possible, such as NSAIDs and aminoglycosides 1, 2
Medication Management
- Avoid diuretics specifically for the prevention or treatment of AKI, unless treating volume overload 1, 2
- Avoid dopamine and recombinant human IGF-1 for prevention or treatment of AKI 1, 2
- Implement therapeutic drug monitoring when using potentially nephrotoxic medications that cannot be avoided 1, 2
Metabolic Management
- Target plasma glucose of 110-149 mg/dL in critically ill patients 1, 2
- Provide total energy intake of 20-30 kcal/kg/day 1, 2
- Administer protein at 0.8-1.0 g/kg/day in noncatabolic AKI patients without need for dialysis, 1.0-1.5 g/kg/day in patients with AKI on RRT, and up to 1.7 g/kg/day in patients on CRRT and hypercatabolic patients 1, 2
- Provide nutrition preferentially via the enteral route 1, 2
Renal Replacement Therapy (RRT) Considerations
- Consider RRT when there are severe metabolic derangements such as:
- For hemodynamically unstable patients, continuous RRT is more physiologically appropriate than intermittent hemodialysis 2
- When using intermittent or extended RRT, deliver a Kt/V of at least 1.2 per treatment 3 times a week 2
- For continuous RRT, deliver an effluent volume of 20-25 ml/kg per hour 2
Special Considerations for AKI in Cirrhosis
- Hold diuretics and nonselective beta-blockers when AKI is diagnosed in patients with cirrhosis 1, 2
- Replace fluid losses, administering albumin 1 g/kg/day for 2 days if serum creatinine shows doubling from baseline 1, 2
- For hepatorenal syndrome with AKI, initiate albumin with vasoactive agents 1, 2
Follow-up After AKI
- Target follow-up to high-risk populations, including patients with baseline CKD and those with severe AKI or incomplete recovery of kidney function at discharge 1, 2
- Monitor for development or progression of chronic kidney disease 1, 2
- Assess for proteinuria, which is associated with worse long-term outcomes after AKI 2
Common Pitfalls and Caveats
- Excessive fluid administration can worsen outcomes; fluid overload and venous congestion have adverse effects on kidney function 2, 3, 4
- While albumin is generally not recommended as initial fluid therapy, it may be beneficial in specific scenarios, such as patients with cirrhosis and spontaneous bacterial peritonitis 1
- Rapid or early excessive fluid removal with diuretics or extracorporeal therapy might lead to hypovolemia and recurrent renal injury 4, 5
- Optimal management might involve a period of guided fluid resuscitation, followed by management of an even fluid balance and, finally, an appropriate rate of fluid removal 4, 5
- Biomarkers should not be used alone when deciding whether to initiate RRT 2
- Avoidance of nephrotoxins is not always possible when treating certain infections; in these cases, careful monitoring and dose adjustment are essential 1, 2