Renal: AKI

Question 1

This process is defined by:

• urea/nitrogen retention
• dysreg of volume status and lytes
• based on GFR or urine output

Answer 1

AKI

Question 2

KDIGO defines AKI as…

Answer 2

increased Cr of 0.3 + within 48 hrs

OR

Increased Cr by 50% in 7 days

OR

urine output < 0.5 ml/kg/hr for > 6 hours

Question 3

Which KDIGO stage?

increased Cr of 0.3 + within 48 hrs

OR

Increased Cr by 50-99% in 7 days

OR

urine output < 0.5 ml/kg/hr for > 6-12 hours

Answer 3

stage 1

Question 4

Which KDIGO Stage?

Increased Cr by 100-199% in

OR

urine output < 0.5 ml/kg/hr for > 12-24 hours

Answer 4

Stage 2

Question 5

Which KDIGO stage?

increased Cr of 0.3 to 0.4+

OR

Increased Cr by 200+%

OR

urine output < 0.3 ml/kg/hr for 24+ hours

OR

anuria for 12+ hours

OR

Renal replacement therapy

Answer 5

stage 3

Question 6

AKI develops in what percent of ICU patients?

Answer 6

60%

Question 7

What is the MC type of AKI in hospitalized patients?

Answer 7

pre-renal

Question 8

Which type of AKI?

decreased renal perfusion

Answer 8

pre-renal

Question 9

Which type of AKI?

pathology of vessels, glomeruli or tubules

can be caused by acute tubular necrosis

Answer 9

intrinsic renal

Question 10

Which type of AKI?

obstruction

Answer 10

post-renal

Question 11

Can etiologies of AKI overlap?

Answer 11

yes! decreased perfusion can lead to acute tubular necrosis (pre-renal + intrinsic)

Question 12

Rank the incidence of AKI types

Answer 12

ATN (45%) > Prerenal (20% > obstruction (10%)

Question 13

5 things that can cause pre-renal AKI…

Answer 13

true volume depletion
hypotension
edema
renal artery ischemia
GFR drugs

Question 14

Which two drugs can affect GFR and cause pre-renal AKI?

Answer 14

NSAIDs and ACE-Is

Question 15

What are three causes of intrinsic renal AKI?

Answer 15

renal ischemia
sepsis
nephrotixins

Question 16

What are nephrotoxins that may cause intrinsic renal AKI?

Answer 16

Abx (vanco/aminoglycosides)

IV contrast

Cisplatin

HIV meds

IVIG

Mannitol

Question 17

Three major risk factors for ATN caused by IV contrast

Answer 17

renal dz
volume depletion
repeat dosing

Question 18

What are the two mechanisms by which contrast can cause AKI?

Answer 18

tubular epithelial toxicity

medullary ischemia from vasoconstriction

Question 19

What are 4 prevention factors for IV induced AKI?

Answer 19

hydration

low osmolal agents at low doses

avoid repeat dose

avoid nephrotoxics for 48 hours after

Question 20

A decreased GFR without intrinsic renal disease requires what kind of obstruction?

Answer 20

bilateral

Question 21

Post-renal AKI is often caused by what three things?

Answer 21

Prostate disease

Mets

neurogenic bladder

Question 22

urine output of > 400mL/24 hours…

Answer 22

nonoliguric

Question 23

urine output of < 400 mL/24 hours

Answer 23

oliguric

Question 24

Urine output < 50 to 100mL/24 hours

Answer 24

anuric

Question 25

Labs for AKI...

Answer 25

UA, CMP + CR/BUN, GFR, FENa

Question 26

Imaging for AKI...

Answer 26

Renal US

Question 27

Is biopsy used for AKI?

Answer 27

yes

Question 28

UA should be examined at ______ temperature within _____ hours

Answer 28

room temp w/in 2 hours

Question 29

Muddy brown casts indicate...

Answer 29

ATN

Question 30

Normal serum Cr for men...

Answer 30

0.6-1.2

Question 31

Normal serum Cr for female...

Answer 31

0.5-1.1

Question 32

Calculating GFR given creatinine...

Answer 32

1/factor of normal cr | ex. 2x Cr = GFR 1/2 of normal, 3x Cr = GFR 1/3 of normal, etc.

Question 33

FENa is a measure of sodium in urine. It helps distinguish what?

Answer 33

prerenal AKI or ATN

Question 34

FENa < 1% indicates... FENa > 2% indicates...

Answer 34

< 1% = prerenal > 2% = intrarenal/ATN

Question 35

What are two pitfalls of FENa?

Answer 35

unreliable if on duretics, Cr not stable in AKI

Question 36

Major reason for imaging with AKI...

Answer 36

obstruction/hydronephrosis

Question 37

MC type of imaging for AKI...

Answer 37

US

Question 38

renal fxn after relief of obstruction is dependent on...

Answer 38

severity and duration of obstruction

Question 39

If no clear AKI etiology, severe disease or increased rate of decline (markedly elevated Cr or worsening), what should be performed?

Answer 39

kidney bx

Question 40

This is a definitive diagnostic that may allow therapeutic intervention to prevent ESRD...

Answer 40

kidney bx

Question 41

How often is Bx used to dx AKI?

Answer 41

rarely

Question 42

The following are C/I for... ``` bleeding diathesis severe HTN pylo tumor solitary kidney ```

Answer 42

Biopsy

Question 43

The following are life threatening complications of... ``` volume imbalance acidosis hyperkalemia hyperphosphatemia hypocalcemia uremia ```

Answer 43

AKI

Question 44

Severe AKI can have what severe sign?

Answer 44

AMS

Question 45

Life threatening complications of AKI require...

Answer 45

hemodialysis

Question 46

What should be assessed in all patients with AKI?

Answer 46

volume status

Question 47

A patient presents with the following. How should they be treated? - hx of fluid loss - hypovolemia on PE - oliguria

Answer 47

fluid challenge via 0.9 NS to confirm pre-renal cause

Question 48

How much fluid should you begin with for a fluid challenge to assess pre-renal AKI?

Answer 48

1-3 L with repeated clinical assessment

Question 49

If a patient doesn't respond to fluid challenge, what etiology is likely?

Answer 49

intrinstic AKI/ATN

Question 50

In patients that are NOT anuric, what can be given to temporarily relieve hypervolemia?

Answer 50

diuretics

Question 51

What offers the most efficient method of fluid volume removal?

Answer 51

dialysis

Question 52

Two considerations of diuretic use for volume overload...

Answer 52

1. not prolonged/temporizing measure | 2. monitor urine output

Question 53

what condition can cause a loss of bicarb and worsen metabolic acidosis?

Answer 53

diarrhea

Question 54

Tx of metabolic acidosis has two options...

Answer 54

dialysis bicarb

Question 55

Dialysis or Bicarb? not volume overloaded acidosis due to diarrhea pH < 7.1 and waiting on dialysis no other acute dialysis indications

Answer 55

Bicarb

Question 56

Dialysis or Bicarb? volume overload severe metabolic acidosis (< 7.1)

Answer 56

dialysis

Question 57

Bicarb admin in hypervolemic patients should be avoided for what reason?

Answer 57

it is administered with fluids

Question 58

hyperkalemia is generally axs, but can occur with...

Answer 58

impaired neuromuscular transmission arrhythmia

Question 59

what are two treatments for hyperkalemia?

Answer 59

medical therapy, dialysis

Question 60

increased serum phosphorus due to reduced GFR is a common cause of...

Answer 60

hypocalcemia

Question 61

the below are sxs of... Paresthesia, tetany, confusion, seizures. Trousseau's and Chvostek's sign. prolonged QT

Answer 61

hypocalcemia

Question 62

how do you tx hypocalcemia?

Answer 62

IV calcium if symptomatic

Question 63

If hypocalcemia is asymptomatic in presence of hyperphosphatemia, what is the initial therapy?

Answer 63

correction of hyperphosphatemia?

Question 64

How do you treat hyperphosphatemia? What about low calcium? High calcium?

Answer 64

dietary phosphate binders low: calcium acetate or carbonate high (non-calcium sources): aluminum hydroxide or lanthhum carbonate

Question 65

Is uremia more common in chronic or acute kidney disease?

Answer 65

chronic

Question 66

the following signs of uremia indicate tx with... pericarditis (friction rub) neuropathy (asaterixis) unexplained AMS

Answer 66

dialysis

Question 67

Do most patients with AKI recover renal function?

Answer 67

yes: UOP and Cr normalize

Question 68

AKI makes you more susceptible for...

Answer 68

CKD, ESRD

Question 69

mortality rate for ICU patients with AKI is...

Answer 69

> 50%