3. Therapy of AKI

Question 1

What are the general measures of treatment of AKI?

Answer 1

• Diagnose what type of AKI is present
• Volume status assessement:
  
  • Urine volume, non-visible JVP, poor skin turgor, hypotension, tachycardia
• Signs of fluid overload: hypertension, increased JVP, lung crepitation, peripheral edema, gallop rhythm on cardiac auscultation
• K⁺-containing fluids should be avoided unless the patient is hypokalemic
• Stop nephrotoxic drugs: NSAID, ACEI, gentamicin, amphotericin
• Stop methformin if creatinin >150mM (may lead to lactic acidosis)
• Check and adjust the doses of renally excreted drugs

Question 2

What is the treatment in case of prerenal AKI?

Answer 2

• Treat underlying cause
• If volume depletion (dehydration, hemorrhage, burn, …):
  
  • Fluid rescucitation using crystalloids (aqueous solutions containing mineral salts and other solutes)
    
    • May help to reverse the injury
  • Stop ACEI, ARB, NSAID and diuretics
• If effective volume depletion (edema, ascites, CHF):
  
  • Na⁺ and water restriction
  • Stop ACEI, ARB, NSAIDs
  • Step-up diuretics (furosemide)
  • Optimise cardiac function

Question 3

What is the treatment in case of intrinsic renal failure?

Answer 3

• Determine the cause of the disease through biopsy and treat the intrinsic kidney disease
• Supportive therapy if ATN develops
  
  • Dialysis for short term
  • Correction of electrolytes
  • …
• Treat prerenal disease or sepsis (stop the renal ischemia)
• Stop nephrotoxic drug!
• If oliguric –> diuretics (furosemide)

Question 4

What is the treatment in case of post-renal AKI?

Answer 4

• Ensure urine flow:
  
  • Bladder catheter
  • Percutaneous transrenal drain
• In case of hydronephrosis:
  
  • Cytoscopy + retrograde stent and nephrostomy insertion can buy time to treat obstruction (mass or stone)

Question 5

How do you manage complications?

Answer 5

• Hyperkalemia: Calcium, glucose + insuline, K⁺ wasting drugs
• Pulmonary edema: diuretics
• Uremia: May require dialysis if severe complications (encephalopathy, pericarditis), otherwise symptomatic treatment
• Acidemia: may require dialysis. Consider NaHCO3 orally or IV

Question 6

What is the last resort treament of AKI therapy?

Answer 6

Renal replacement therapy (topic 5):

• Includes hemodialysis and hemofiltration