Management of Acute Kidney Injury (AKI)

Definition and Diagnosis

AKI is defined by any of the following: increase in serum creatinine by ≥0.3 mg/dL within 48 hours; increase in serum creatinine to ≥1.5 times baseline within 7 days; or urine output <0.5 mL/kg/h for 6 hours, as defined by the Kidney International guidelines 3
AKI is staged for severity according to changes in serum creatinine and urine output, with higher stages associated with worse outcomes, according to the Kidney International guidelines 3
Pathophysiology includes intrinsic renal pathology and extrinsic factors, as described in the BMJ 4, 5
Biochemical tests should include serum urea, creatinine, electrolytes at least every 48 hours or more frequently in high-risk patients, as recommended by the BMJ 4, 5

Conduct rigorous search for infection and perform diagnostic paracentesis in patients with cirrhosis to evaluate for spontaneous bacterial peritonitis, as recommended by Clinical Gastroenterology and Hepatology 6
Discontinue nephrotoxic medications unless essential, as recommended by the BMJ 4, 5
Hold diuretics and nonselective beta-blockers when AKI is diagnosed, as recommended by Clinical Gastroenterology and Hepatology 6
Avoid using dopamine, diuretics, N-acetylcysteine, or recombinant human insulin-like growth factor 1 for treatment of AKI, as recommended by the American Journal of Kidney Diseases 1

Use isotonic crystalloids rather than colloids for initial management of volume expansion, as recommended by the American Journal of Kidney Diseases 1
Target euvolemia through careful assessment of fluid balance, as recommended by the BMJ 4, 5
Monitor fluid status by clinical examination and fluid balance daily, as recommended by the BMJ 4, 5

When serum creatinine remains higher than twice baseline despite initial measures, treat with albumin plus vasoactive agents for Hepatorenal Syndrome (HRS-AKI), as recommended by Clinical Gastroenterology and Hepatology 6
Consider RRT for severe complications of AKI, as recommended by the American Journal of Kidney Diseases 8
CRRT is preferable in hemodynamically unstable patients and those with acute brain injury, as recommended by the American Journal of Kidney Diseases 8

Monitor patients for development or progression of chronic kidney disease after AKI, as recommended by the BMJ 4, 5
Consider follow-up evaluation for patients with risk factors for progression to CKD, particularly those who suffered severe AKI requiring temporary RRT, as recommended by the American Journal of Kidney Diseases 1