05.15 - AKI (Canada) - PP Flashcards Preview

Renal > 05.15 - AKI (Canada) - PP > Flashcards

Flashcards in 05.15 - AKI (Canada) - PP Deck (56):
1

3 Clinical Clues to ATN

(1) Muddy brown granular casts; (2) Urine Na > 20; (3) Fractional excretion of Na > 1%

2

Urinarlysis in Hepatorenal Syndrome

Usually normal

2

Urine Na in HRS

Very low (Aldosterone)

2

Urine in Acute Interstitial Nephritis

Pyuria +/- eosinophils

3

Effect of Aminoglycosides on Kidney

Inhibits normal lysosomal function, accumulates in PT cells

4

What can you do in suspected HRS to rule out simple pre-renal condition

Trial of volume (usually Albumin) infusion

5

Urine [Na] and Osm in Pre-Renal AKI

Very low Na (Aldosterone overactive), Very high osmolarity (ADH overactive)

5

Why is urine Na high in ATN

Necrotic tubular cells can't reabsorb Na so excreted

6

___ can cause form of pre-renal AKI in patients with Bilateral RAS

ACEi's and ARB's

6

Main 2 Causes of ATN

Ischemic injury; Toxic injury from contrast or meds

6

Symptoms of Acute Interstitial Nephritis in most patients now

Only renal dysfunction

7

2 Therapeutic agents that cause Pre-Renal AKI

NSAIDs, ACEi's

8

What does survival in Hepatorenal Syndrome depend on

Liver transplant

9

How to avoid Contrast Nephropathy

Avoid closely spaced studies

10

Acute Kidney Injury is essentially

Impairment of GFR

10

BP and ECV in Hepatorenal Syndrome

Decrease BP despite incr ECFV (decr ECV)

10

Histology of ATN

Tubular necrosis with denuding of renal tubular epithelial cells; Occlusion of tubular lumens with cells/casts

10

Acute Interstitial Nephritis is most commonly caused by

Beta Lactam Abx, NSAIDs

12

Most common cause of Post-renal AKI

Prostate disease

12

(1) Muddy brown granular casts; (2) Urine Na > 20; (3) Fractional excretion of Na > 1%

3 Clinical Clues to ATN

14

Worsening renal failure in setting of cirrhosis =

Hepatorenal syndrome

15

Must rule out what else to conclude HRS

NSAIDs, Nephrotoxic drugs, Contrast

17

BUN/Cr in Pre-Renal vs ATN

>20:1 in Pre-Renal; 10-15:1 in ATN

17

Why is Uosm high in Pre-Renal and Normal in ATN

High Aldo in Pre-Renal; In ATN, necrotic cells can't dilute or concentrate so same as blood

19

Most common class of AKI? Second?

55% Pre-renal, 40% intrinsic

21

Calyce visible on renal US means

Obstruction of outflow

22

2 Aminoglycosides

Gentamycin, Topomycin

23

How do contrast agents cause AKI

Direct vasoconstrictive effects on arterioles; Also directly toxic

25

Usual symptoms of AKI

Usually asymptomatic and discovered on routine labs

26

Why do ACEi's cause Pre-Renal AKI

Inhibit Ang2 which selectively constricts efferent arterioles

27

Oliguria is defined as

Less than 400mL / 24 hours

28

Muddy Brown Casts =

ATN

28

Management of Ischemic ATN

Treat underlying cause - Restore perfusion

29

FENa in Pre-Renal vs ATN

Less 1% in Pre-Renal; Greater than 1% in ATN

31

Timeframe of AKI

Rapid deterioration of kidney function < 1 month

32

Hepatorenal syndrome results from what liver disease

Cirrhosis

33

UNa+ in Pre-Renal vs ATN

Less than 20 mEq/L in Pre-Renal; Greater than 25 mEq/L in ATN

34

How do you prevent Aminoglycoside toxicity

Once daily dosing; Minimize duration of tx

36

Impairment of GFR (AKI) leads to

Elevation of BUN/Creatinine, Accumulation of substances/drugs normally excreted by kidney

37

Inhibits normal lysosomal function in kidney

Aminoglycosides

38

3 Specific Types of Pre-Renal AKI

(1) Hepatorenal Syndrome; (2) RAS and Ang2 blockers/ACEi's; (3) Other drugs that impair autoregulation (NSAIDs)

39

2 causes of Post-renal AKI other than prostate

Malignancies, Neurogenic bladder

40

ACEi's and ARB's can cause ___ in patients with Bilateral RAS

Pre-Renal AKI

41

Decreased levels or inhibition of Ang2 impairs renal ____

Auto-Regulation (constriction of efferent arterioles in RAS)

43

Dx of Post-renal AKI

Foley catheter, US

45

Uosm in Pre-Renal vs ATN

>500 mOsm/kg vs 300-350 mOsm/kg

46

As BP falls, kidneys are able to maintain BP well, unless __

Ang2 blocker interferes with Efferent Arteriole vasoconstriction (impaired autoregulation)

47

Urine output in AKI

Sometime decr, but not always

48

Hyaline casts are seen in what type of kidney injury

Pre-renal AKI

50

Most accurate test for Pre-Renal AKI

Fractional excretion of Na - If less than 1%, suggestive of pre-renal

51

U/A in Pre-Renal vs ATN

Hyaline Casts vs Granular Casts

52

Creatinine change criteria for AKI

Greater than 0.5mg/dL incr or incr of 50% over baseline

53

Most important cause of Intra-renal AKI discussed

ATN

54

Pre-Renal AKI is due to insufficiency of

Renal perfusion

55

Urinalysis in Post-renal AKI

Unremarkable

56

How do NSAIDS cause Pre-Renal AKI

Block PG's that dilate the afferent arterioles