acute kidney injury 2

Question 1

what type of test is often done to see if there is kidney blockage, or a structural issue with the kidney?

Answer 1

renal imaging (ultrasonogram)

Question 2

what are two types of prerenal hypoperfusion?

Answer 2

1. systemic hypoperfusion

2. isolated renal hypoperfusion

Question 3

what indicates isolated renal hypoperfusion

Answer 3

bilateral renal artery stenosis embuli

cholesterol or thrombotic

Question 4

what indicates systemic hypoperfusionq

Answer 4

1. intravascular volume depletion

2. relative decrease in volume

Question 5

what are 3 things that indicate intravascular volume depletion by systemic hypoperfusion

Answer 5

1. dehydration
2. hemorrhage
3. overdiuresis

Question 6

what are 3 things that indicate relative decrease in volume due to systemic hypoperfusion

Answer 6

1. heart failure
2. liver disease
3. nephrotic syndrome

Question 7

what is nonoliguric disease typically classified as prerenal decreases GFR and usually stops when agent causing it is removed?

Answer 7

functional acute renal failure

Question 8

what do ACE inhibitors inhibit?
what does this cause?
where?

Answer 8

angiotensin II

Question 9

what general change causes functional acute renal failure?

Answer 9

hemodynamic changes ( no direct kidney pressure)

Question 10

what two endogenous compounds are the main factors for vasodilation and vasoconstriction

Answer 10

1. prostaglandins

2. angiotensin II

Question 11

what compound effects the afferent arteriole’s constriction and dilation?

Answer 11

prostaglandins

Question 12

what compound effects the efferent arteriole’s constriction and dilation?

Answer 12

angiotensin II

Question 13

what are the 3 main causes of functional acute renal failure

Answer 13

1. NSAIDs
2. ACEI’s and ARB’s
3. Calcineurin inhibitors (immunosuppresents, ie cyclosporine)

Question 14

what is the MOA of ACEI/ARB induced AKI?

Answer 14

vasodilation of efferent arteriole (leaving kidney)

Question 15

angiotensin II causes what?

Answer 15

vasoconstriction

Question 16

what can commonly be seen lab values that appears significant at the start of an ACEI?

Answer 16

rise in SCr of less than 30%

Question 17

why should ACE inhibitors be started at low doses and slowly increased

Answer 17

due to vasodilation increasing SCr

Question 18

what are 4 conditions that can exacerbate change in renal function with ARBs and ACEI’s?

Answer 18

1. dehydration
2. renal artery stenosis
3. CHF
4. Cirrhosis
   (still can use with these pt’s just monitor closely)

Question 19

what accounts for around 37% of drug induced AKI

Answer 19

NSAID’s

Question 20

what enzyme is essential for maintaining renal hemodyanamics, effected by NSAIDs

Answer 20

COX-2

Question 21

NSAID’s cause what problem, where leading to AKI?

Answer 21

constriction of afferent arteriole, leading to hypoperfusion

Question 22

what are two common calcineurin inhibitors

Answer 22

tacrlimus

cyclosporine

Question 23

what are calcineurin inhibitors often used for?

how long are pt’s at risk of CKD after this

Answer 23

post transplant immunosuppressant’s

5 years after transplant of nonrenal organ

Question 24

what is the dose limiting adverse effect of tacrolimus and cyclosporine (calcineurin inhibitors)?

Answer 24

nephrotoxicity

Question 25

when does nephrotoxicity normally present with cyclosporine therapy

Answer 25

within 6 months of cyclosporine therapy

Question 26

what MOA do calcineurin inhibitors have to cause ARF

Answer 26

reversible, but extreme vasoconstritction and injury to afferent arteriole

Question 27

what are 2 causes of functional ARF other than drug induced

Answer 27

1. hypercalcemia - direct vasoconstriction

2. hepatorenal syndrome - ARF in pt’s with severe liver disease (probably mediated by prostaglandins)

Question 28

when prerenal or functional ARF are seen what should be thought of immediately as cause?
what should be the next step in diagnosis

Answer 28

hypoperfusion

is it systemic hypoperfusion or renal hypoperfusion