What is the management of Acute Kidney Injury (AKI)?

Management of Acute Kidney Injury

Immediate Actions Upon AKI Recognition

Discontinue all nephrotoxic medications immediately, including ACE inhibitors, ARBs, NSAIDs, and diuretics—this is the single most critical intervention to prevent progression. 1

Medication Review and Drug Stewardship

• Review all medications including over-the-counter drugs and herbal products 2
• Withdraw vasodilators and any potentially nephrotoxic agents 2
• Avoid combining nephrotoxins, as each additional nephrotoxin increases AKI odds by 53%, and combining three or more nephrotoxins results in AKI in 25% of non-critically ill patients 2
• Be particularly cautious with macrolide-statin combinations (clarithromycin or erythromycin with statins increase rhabdomyolysis-related AKI) 2
• Adjust all prescribed drugs according to renal function 3

Volume Status Assessment and Fluid Management

Assess volume status through clinical examination, vital signs, and urine output—consider central venous pressure monitoring in complex cases. 1

For Hypovolemic Patients

• Provide fluid resuscitation with isotonic crystalloids rather than colloids 2, 1
• In cirrhosis patients with clinically suspected hypovolemia, use crystalloids, albumin, or blood (if AKI resulted from GI bleeding) 2

For Cirrhosis-Specific AKI Management

• If serum creatinine does not respond to initial measures and shows doubling from baseline, administer albumin 1 g/kg/day (maximum 100 g/day) for 2 consecutive days 2, 1
• Perform diagnostic paracentesis to evaluate for spontaneous bacterial peritonitis 1
• Start broad-spectrum antibiotics when infection is strongly suspected 1

Hemodynamic Support

• Maintain mean arterial pressure >65 mmHg to ensure adequate renal perfusion 1
• Determine optimal vasopressor targets based on clinical context 1

Determine the Underlying Cause

Classify AKI as prerenal, intrinsic renal, or postrenal with special attention to reversible causes. 1

Diagnostic Workup

• Obtain complete blood count, serum creatinine, BUN, and urinalysis 4
• Calculate fractional excretion of sodium 4
• Perform renal ultrasonography in most patients, particularly older men, to rule out obstruction 4
• Monitor serum electrolytes, BUN, and creatinine every 4-6 hours initially 1

Stage-Based Monitoring Intensity

While the KDOQI commentary expresses concerns about rigid stage-based management protocols 2, severity should guide monitoring frequency:

• Stage 1 AKI: Close monitoring, remove risk factors, plasma volume expansion if hypovolemic 2
• Stage 2-3 AKI: Withdraw diuretics (if not already done), albumin expansion (1 g/kg for 2 days), consider ICU admission 2

Management of Complications

• Correct electrolyte abnormalities, particularly hyperkalemia requiring urgent intervention 1
• Monitor for uremic complications (encephalopathy, pericarditis, pleuritis) 4
• Address metabolic acidosis 1

Renal Replacement Therapy Indications

Initiate RRT urgently for: 1, 4

• Refractory hyperkalemia unresponsive to medical management
• Severe volume overload despite diuretics
• Intractable metabolic acidosis
• Uremic complications (encephalopathy, pericarditis, pleuritis)
• Severe oliguria unresponsive to fluid resuscitation
• Certain toxin removal

Reassess the need for continued RRT daily. 1

Post-Discharge Follow-Up

Schedule close post-discharge evaluation for patients with moderate to severe AKI, with timing based on AKI severity. 2, 1

• Stage 3 AKI: Requires far earlier post-discharge follow-up 2
• Stage 1 AKI: Risk-stratify based on baseline CKD presence and degree of recovery 2
• Highest-risk populations requiring targeted follow-up: neonatal/pediatric patients, individuals with baseline CKD, patients with severe AKI or incomplete recovery at discharge 2
• Assess creatinine every 2-4 days during hospitalization and at least every 2-4 weeks during first 6 months after discharge for those who responded to treatment 2

Critical Pitfalls to Avoid

• Delaying RRT when clear indications exist increases mortality 1
• Failing to identify and address the underlying cause 1
• Continuing nephrotoxic medications during AKI recovery 1
• Waiting until Stage 2 to check drug dosing adjustments—this should be done earlier 2
• Indiscriminate fluid administration based on misinterpretation of "prerenal" AKI as purely hypovolemic 5
• Treating asymptomatic bacteriuria in AKI patients 6

Prevention in At-Risk Patients

• Identify high-risk patients: older age, diabetes, chronic kidney disease, heart failure, sepsis, cardiac surgery 1, 4
• Ensure adequate hydration before contrast procedures 1
• Implement pharmacist-led quality-improvement programs to reduce nephrotoxic exposures 3