Acute Kidney Injury (AKI) Best Practices

What follows is a summary of best practice recommendations based upon the Kidney Disease: Improving Global Outcomes (KDIGO) and the National Institute for Health and Care Excellence (NICE) guidelines. Please contact us with any questions, concerns, or additions.

KDIGO AKI Definition: AKI is defined as an absolute increase in serum creatinine by 0.3mg/dl within 48 hours or a relative increase of 50% within 7 days. While urine output criteria can also define AKI, these criteria are not used in the AKI Alert study.

AKI Workup

  • Evaluate for pre-renal causes

    • Clinical situation - poor intake? Excessive losses? Nausea/vomiting, Diarrhea? Increased intra-abdominal pressure? Decompensated cirrhosis? Decompensated heart failure?

    • Physical exam - blood pressure (including orthostatics), jugular venous pressure, capillary refill

    • Workup - urinalysis, urine electrolytes, urine creatinine, urine urea nitrogen (for patients on diuretics), complete metabolic panel, CBC with differential

 

  • Evaluate for Urinary Obstruction

    • Clinical situation – male? Prostate disease? Other intra-abdominal pathology?

    • Physical exam – distended bladder?

    • Workup: Post-void residual (Foley or straight cath if ascites present), Renal ultrasound

 

  • Evaluate for Intrinsic Renal Injury

    • Clinical situation

      • Tubular Injury - exposure to nephrotoxic drugs / contrast? Hypotension? Sepsis?

      • Glomerular Injury - Systemic signs of vasculitis (eg rash)

      • Vascular injury – Risk factors (such as recent vascular procedure or surgery)? Other stigmata of systemic embolism?

      • Interstitial injury - Exposure to a medication associated with AIN? Rash?

    • Workup

      • Urinalysis + urine microscopy: cellular casts? Hematuria?

      • CBC with diff (platelet count, eosinophil count)

  • When is a renal consult appropriate?

    • Whenever the care team has a question or concern about the patient

    • Unclear etiology of AKI

    • Progressive AKI despite optimal care

    • Concerning urinalysis findings: red cell casts, significant proteinuria

    • Electrolyte/Acid base abnormalities (hyperkalemia, severe metabolic acidosis)

    • Refractory volume overload 

    • Uremia (pericardial rub, encephalopathy)

    • Exposure to methanol or other toxin, drug overdose of dialyzable substance (eg lithium)

    • Anuria

    • Indications for urgent dialysis

 

  • Management

    • Best practices

      • Follow-up serum creatinine measurements

      • Fluid "ins and outs" recording

      • Daily weights

      • Daily Clinical / Volume Assessment

      • Drug dosing review

      • Optimize hemodynamics

      • Avoid nephrotoxic agents if possible such as:

        • Iodinated contrast

        • Non-steroidal anti-inflammatory drugs (NSAIDs)

        • Aminoglycosides (if possible)

        • Chemotherapeutic agents (platins, etc)

        • Amphotericin B

      • Consider holding diuretics if no overt volume overload