Intrinsic AKI

Question 1

Definition of AKI

Answer 1

Abrupt reduction in kidney fxn: Increase in serum creatinie of >=.3mg/dl or >=50% or documented oliguria

Question 2

what is the obligatory solute load?

Answer 2

.5 L/day.

Question 3

define oliguria. anuria

Answer 3

oliguria<.1L/d

Question 4

what state must you be in to calculate GFR

Answer 4

steady state

Question 5

When is a FE Urea better tahn FENa?

Answer 5

when on diuretics

Question 6

What are the three main types of intrinsic ARF?

Answer 6

Tubular, Glomerular, interstitial

Question 7

What are the two principle causes of tubular IRF?

Answer 7

ischemic, toxic

Question 8

What is the most common cause of ischemic ATN? What would the urnine lytes show? Urinalysis?

Answer 8

prerenal azotemia. Na>40, FENa>1%, Urine osms ~300. dark, granular casts

Question 9

Normotensive ischemic AKI

Answer 9

someone with impaired autoregulation has chronic high BP so with regular BP they are underperfused

Question 10

how does filtration fraction change with afferent artery dilation? what causes it? afferent constriction? cause?

Answer 10

prostaglandins, doesn’t change much b/c it inreases GFR as well as RPF. No change, equal decrease in GFR and RPF. NSAIDS (decrease PGs)

Question 11

How does Efferent art. dilation change FF? causes? Constriction? causes?

Answer 11

ACE-I, ARB. decreased FF….AT2, increases GFR

Question 12

what are the main causes of toxic ATN? Definition? Mechanism?

Answer 12

Radiocontrast nephropathy. increase in cr > .5mg or 25%. Directly toxic and induces vasospasm (ischemia). Pigment Nephropathy=muscle (myoglobin) or hemolysis (hemoglobin) toxicity

Question 13

Acute interstitial nephritis

Answer 13

result of medication. associated w/ fever, rash, eosinophilia plus hematuria

Question 14

What gives you a pigmented granular cast?

Answer 14

ATN

Question 15

Rhabdomyolysis

Answer 15

Muscle damage causes myoglobin release and toxic ATN