Wk 3 Acute Kidney Injury Flashcards
What does acute kidney injury result from?
Ischemic injury
What can cause ischemic injury?
Volume depletion and decreased perfusion
Toxic injury from chemicals
Sepsis
The ischemic injury initiations what 3 responses?
Inflammatory
Vascular
Cell death
What are the 3 classifications of AKI?
Prerenal
Intrarenal
Postrenal
Prerenal means
before the kidney
The most common cause of pre renal AKI
inadequate perfusion
What are causes of inadequate perfusion? (6)
Hypotension Hypovolemia Sepsis Decreased CO Renal vasoconstriction Renal artery stenosis
What is renal artery stenosis?
Narrowing of one or more arteries that carry blood to your kidneys
What else can cause inadequate perfusion to the kidneys?
Contrast agents that are nephrotoxic
In pre renal AKI, the GFR is
decreased
Why is the GFR decreased in pre renal AKI
due to low glomerular filtration pressure
What can cause ischemic cell injury and necrosis?
Failure to restore BV, BP, and O2 delivery
What is intra renal AKI?
Injury occurs IN the kidney
What is the most common cause of intrarenal AKI?
acute tubular necrosis (ATN)
What is acute tubular necrosis related to? (4)
Prerenal AKI
Nephrotoxic agents
Acute glomerulonephritis
Vascular disease
Prerenal AKI can become…
Intrarenal AKI
__ and __ cause ischemia and inflammatory response in kidney
Hypotension and hypovolemia
What 4 things can cause nephrotic acute tubular necrosis?
Abx
Heavy metals
Contrast dye
Rhabdomyolysis
What antibiotics can cause nephrotic acute tubular necrosis?
aminoglycosides
What do you see with rhabdomyolysis?
Breakdown of skeletal muscle and release of excessive myoglobin
What causes the damage to the kidneys in rhabdomyolysis?
The release of excess myoglobin
What type of injury can cause rhabdomyolysis?
Crush injuries
Drug overdose
What is post renal AKI?
Rare condition that occurs with urinary tract obstruction
5 causes of post renal AKI
Bladder outlet obstruction Prostatic hyperplasia Bilateral ureteral obstruction Tumor Neurogenic bladder
What does the obstruction cause in post renal AKI?
Increased renal pressure proximal to the obstruction
How fast does AKI occur?
within hours
What would the GFR be in AKI?
Decreased
What is a normal GFR?
Greater than 90
What is a normal urinary output?
Greater than 30mls/hr
What would the urinary output be in AKI?
Decreased
What would the BUN be in AKI?
Increased
What is a normal BUN?
10-20 mg/dL
What is a normal creatinine?
0.5-1.2 mg/dL
What would be the creatinine be in AKI?
Increased
AKI may be…
reversible
What is creatinine?
Chemical compound left over from energy production in the muscles
What is urea nitrogen?
Byproduct of protein breakdown
When does oliguria occur in AKI?
1 day after hypotensive event
How long does oliguria last in AKI?
1-3 weeks
Oliguria is defined as…
Less than 400 mls/24 hrs
What is the goal of treatment for AKI?
Stabilize the patient until kidney function is returned
What is important considering electrolyte imbalances in AKI?
Correct fluid imbalance and hyperkalemia
What might be prescribed to increase potassium removal for treatment of hyperkalemia?
furosemide (Lasix)
What helps move potassium back into the cells temporarily? (2)
Insulin
Dextrose
What are 3 potassium binders we can give to move potassium through the GI tract?
sodium polystyrene sulfonate
patiromer
sodium zirconium cyclosilicate
A patient with AKI will have what acid-base imbalance?
Metabolic acidosis
What do we give to treat the acid-base imbalance for AKI?
Sodium bicarbonate
What other 2 things to do for AKI
Manage BP
Avoid nephrotoxic drugs
