Acute Kidney Injury

Question 1

Types of acute renal failure

Answer 1

• Prerenal
  Transient renal hypoperfusion due to hypotension, decreased cardiac output, decreased effective arterial blood volume
• postrenal
  Obstruction of urinary tract
• intrinsic
  Acute glomerulonephritis involves inflammation and damage to the glomerular membrane
  Acute interstitial nephritis, an allergic reaction, may be caused by a variety of drugs
• acute tubular necrosis accounts for more than 50% of cases of acute renal failure- nephrotoxicagents, prolonged renal hypoperfusion

Question 2

Phase of acute renal failure

Answer 2

• acute insult (steady rise in Cr)
• oliguric anuric phase (UO drop to 30ml/hr, often fluid and electrolyte restrictions required
• polyuric/ recovery phase
  Urine made but not always concentrated and can be normal or increased
  Additional fluid and electrolytes may not he required
  Monitor serum potassium and manage accordingly

Question 3

Calculating estimated requirements

Answer 3

ICU >50% mortality rate, metabolic disturbances

Ward- ~10% mortality rate, metabolic disturbances unlikely

Question 4

EN or PN

Answer 4

If oral feeding knot possible initiate enteral feeding within 24 hours
PN only indicated if GI tract not working or EN alone cannot meet requirements
(Do not overfeed >30kcal/kg/day)

Question 5

What if they are eating

Answer 5

Don’t be overly restricted unless required eg K
Monitor and change diets if RRT starts
Monitor fluid balance

Extra fluid may be given to anuric/ olgiuric patients of high fluid requirements in the polyuric phase when AKI is resolving