Chapter 88: Acute Kidney Injury

Question 1

Reversible mechanisms of community acquired AKI

Answer 1

volume depletion
medications
infection
urinary obstruction

Question 2

Wha are the functions of the kidney?

Answer 2

glomerular filtration
tubular reabsorption
secretion

Question 3

normal GFR of early adulthood?

Answer 3

120ml/min/1.73m2

Question 4

every decade, how many decrease in GFR is noted?

Answer 4

8ml/min/1.73m2

Question 5

what is the driving force of glomerular filtrations?

Answer 5

glomerular capillary pressure

Question 6

glomerular capillary pressure depends on 2 things

Answer 6

renal blood flow and autoregulation

Question 7

recovery from AKI depends on what factor?

Answer 7

renal blood flow

Question 8

classification of AKI that increases tubular pressure that decreases the driving force for filtration

Answer 8

postrenal AKI

Question 9

most common cause of intrinsic AKI?

Answer 9

ischemic injury or ischemic tubular necrosis

Question 10

Once the cause of acute kidney injury is resolved, the remaining functional nephrons increase filtration and eventually ___

Answer 10

hyperthrophied

Question 11

If the number of remaining nephrons is below some critical number, continued hyperfiltration results in progressive ___ , eventually leading to ___

Answer 11

glomerular sclerosis

nephron loss

Question 12

causes of endothelial leak that will result in third spacing

Answer 12

sepsis
pancreatitis
burns
hepatic failure

Question 13

AKI that may present as flank pain and hematuria

Answer 13

crystal-induced nephropathy
nephrolithiasis
papillary necrosis

Question 14

what would you suspect in patient with rhabdomyolysis or hemolysis after blood transfusion?

Answer 14

pigment-induced AKI

Question 15

patient presented with darkening of urine and edema

Answer 15

acute glumerulonephritis

Question 16

Fever, arthralgia, and rash are common with ___

Answer 16

acute interstitial nephritis

Question 17

patient presented with severe flank pain

Answer 17

acute renal arterial occlusion

Question 18

Cough, dyspnea, and hemoptysis raise the possibility of ___

Answer 18

Goodpasture’s syndrome or Wegener’s granulomatosis

Question 19

this symptom strongly suggest obstruction

Answer 19

anuria (alternating oliguria and polyuria)

Question 20

Serum Cr increased 2.0–3.0 times or GFR decrease 50%–75% and urine output of 0.5 mL/kg/h for 12 h

Answer 20

AKIN stage 2

RIFLE: Injury

Question 21

Serum Cr increased 1.5 times or (AKIN only) Cr increase >0.3 milligram/dL (≥26.5 μmol/L) over <48 hour or GFR decrease 25%–50% and urine output of 0.5 mL/kg/h for 6 h

Answer 21

AKIN stage 1

RIFLE: Risk

Question 22

Serum Cr increased >3.0 times or Cr >4 milligrams/dL (≥354 μmol/L) and acute increase >0.5 milligram/dL (44 μmol/L) or GFR decrease >75% and urine output of 0.3 mL/kg/h for 24 h or Anuria for 12 h

Answer 22

AKIN stage 3

RIFLE: Failure

Question 23

Need for renal replacement therapy for >3 months

Answer 23

RIFLE: End-stage renal disease

Question 24

Complete loss of kidney function for >4 weeks

Answer 24

RIFLE: Loss

Question 25

T or F: Determine if kidney injury is prerenal, postrenal, or intrin- sic through history, physical, and diagnostic testing

Answer 25

True

Question 26

ECG is the fastest screening test for hyperkalemia, but sensitivity for a level over ___ ranges from 14% to 60%

Answer 26

6.5 mmol/L

Question 27

how many postpaid bladder residual volume suggests bladder outlet obstruction?

Answer 27

>125mL

Question 28

anuria

Answer 28

<100ml/24 hours

Question 29

prerenal AKI can be divided into?

Answer 29

volume loss hypotension diseases of the large and small renal arteries

Question 30

In the elderly population, the rate of postrenal AKI is as high as ___

Answer 30

22%

Question 31

it is a type of AKI that is most common in hospital acquired AKI than community acquired AKI.

Answer 31

intrinsic acute kidney injury

Question 32

definition of contrast-induced nephropathy

Answer 32

change in serum creatinine (25% increase from baseline or an absolute increase of 0.5 milligram/dL [44 μmol/L] 48 to 72 hours after infusion)

Question 33

causes of crystal-induced nephropathy (renal tubule)

Answer 33

elevated uric acid in tumor lysis syndrome, acyclovir, sulfonamides, indinavir and triamterene

Question 34

mechanism of ACE inhibitor in increasing serum creatinine

Answer 34

decrease the GFR and increase renal blood flow

Question 35

arteriolar changes (efferent arteriolar vasodilation) may precipitate significant AKI in a patient with undiagnosed ___

Answer 35

bilateral renal artery stenosis

Question 36

other than increase serum creatinine what is the usually side effect?

Answer 36

mild hyperkalemia

Question 37

mechanism of NSAIDS in increasing serum creatinine?

Answer 37

decrease GFR and renal blood flow (vasoconstriction of afferent arteriolar)

Question 38

type of AKI in NSAIDS use

Answer 38

prerenal initially then post renal in long term use

Question 39

the most common antiviral that causes AKI

Answer 39

antiretroviral such as acyclovir and valacyclovir

Question 40

In patients with no renal function (GFR = 0), serum creatinine level increases ___

Answer 40

1 to 3 milligrams/dL (88 to 265 μmol) a day

Question 41

T or F: Elevation of serum creatinine may take 24 hours after onset of decreased function

Answer 41

False. 48 hours

Question 42

Example of intrinsic AKI that causes rhabdomyolysis

Answer 42

cocaine ethanol lovastatin

Question 43

stages of CKD

Answer 43

``` Stage 1: GFR ≥90 mL/min/1.73 m2 Stage 2: GFR 60–89 mL/min/1.73 m2 Stage 3: GFR 30–59 mL/min/1.73 m2 Stage 4: GFR 15–29 mL/min/1.73 m2 Stage 5: GFR <15 mL/min/1.73 m2 ```

Question 44

A protein produced by all nucleated cells has been proposed as a replacement for creatinine in estimating GFR

Answer 44

cystitis C

Question 45

Exact measurements of urine output require a urinary catheter to be in place for greater than ___ hours to meet the criteria of AKI

Answer 45

6 hours

Question 46

Urea is reabsorbed in tubule with sodium. so in patient with hypernatremia how many percent of urea clearance is low?

Answer 46

30%

Question 47

In the setting of prerenal AKI, the serum ratio of BUN to creatinine is typically ___

Answer 47

>10

Question 48

Pigmented granular casts are common with ___

Answer 48

ischemic or toxic tubular injury

Question 49

This findings in urinalysis is normal in pre renal AKI

Answer 49

hyaline casts

Question 50

Brown granular casts are common in ___

Answer 50

hemoglobinuria or myoglobinuria

Question 51

The finding of hemoglobin on urine dipstick analysis with no red cells on microscopy suggests ___

Answer 51

myoglobinuria

Question 52

kidney dimension of ___ suggests chronic kidney disease

Answer 52

<9 cm

Question 53

Hyperechogenicity in the ultrasound indicates ___

Answer 53

Hyperechogenicity indicates diffuse parenchymal disease

Question 54

This test will allow assessment of renal perfusion and can allow diagnosis of large-vessel causes of AKI.

Answer 54

Color flow Doppler US

Question 55

___ is the ratio of the differ- ence between systolic and diastolic flow to systolic flow [(Vmax – Vmin)/ Vmax]

Answer 55

Resistive index (NV <0.7)

Question 56

In the vasoconstrictive phase of ischemic AKI, in which there may be no diastolic flow, the ratio may be as high as ___

Answer 56

1.0

Question 57

In critically ill patient with AKI. What is the priority of treatment?

Answer 57

resuscitation

Question 58

IF GFR is less than 30 avoid IV contrast except what cases?

Answer 58

major trauma aortic dissection STEMI

Question 59

In general, for IV contrast studies in patients with GFR of ___, weigh benefits of the study against the risk of renal function decline.

Answer 59

30 to 59 mL/min/1.73 m2

Question 60

For patient with abnormal kidney for contrast-enhanced imaging. What fluid we should give?

Answer 60

500 to 1000ml LR prior to procedure and equal amount after procedure

Question 61

Permanent loss of renal function develops over the course of ____ in the setting of complete obstruction

Answer 61

10 to 14 days

Question 62

The risk of chronic kidney disease increases significantly if obstruction is complicated by ___

Answer 62

UTI

Question 63

T or F: n the absence of fluid overload, diuretics are recommended for patients with AKI

Answer 63

False. In the absence of fluid overload, diuretics are not recommended for patients with AKI

Question 64

Furosemide stress test can be done in patient with

Answer 64

mild to moderate fluid overload and AKIN stage 2 and below

Question 65

How to do Furosemide stress test?

Answer 65

Administer 1 milligrams/kg of furosemide in naive patients or 1.5 milligrams/kg in those with prior exposure; a urine output of <200 mL over 2 hours has a sensitivity of 87.1% and a specificity of 84.1% to predict progression to AKIN stage 3 AKI

Question 66

safe effective use of sodium bicarbonate requires ___

Answer 66

urine flow and ability to tolerate a fluid load

Question 67

Treatment for glomerulonephritis

Answer 67

renal biopsy corticosteroid cyclophosphamide plasmapheresis

Question 68

types of cardiorenal syndrome

Answer 68

type 1 - acute deterioration in cardiac function that causes AKI type 2 - chronic type 3 - AKI that causes acute cardiac injury and/or dysfunction type 4 - chronic type 5 - secondary to a separate systemic condition such as sepsis

Question 69

This is a form of renal replacement therapy primarily used to remove excess fluid

Answer 69

Ultrafiltration

Question 70

T or F: U.S. Food and Drug Administration states that metformin should be withheld temporarily in patients receiving iodin- ated contrast media if their GFR is between 30 and 60 mL/min/1.73 m2 and restarted after creatinine has been checked 48 hours after contrast administration, and patients with lower GFRs should have metformin held and not restarted

Answer 70

True. U.S. Food and Drug Administration states that metformin should be withheld temporarily in patients receiving iodin- ated contrast media if their GFR is between 30 and 60 mL/min/1.73 m2 and restarted after creatinine has been checked 48 hours after contrast administration, and patients with lower GFRs should have metformin held and not restarted

Question 71

T or F: The American College of Radiology has made the following recommenda- tions. For patients with estimated GFR ≥30 mL/min/1.73 m2, there is no need to discontinue metformin prior to the procedure or following the procedure

Answer 71

True. The American College of Radiology has made the following recommenda- tions. For patients with estimated GFR ≥30 mL/min/1.73 m2, there is no need to discontinue metformin prior to the procedure or following the procedure

Question 72

T or F: For patients with eGFR ≤30 mL/min/1.73 m2, metformin should be withheld at the time of the contrast infusion and for 48 hours after the procedure

Answer 72

True. For patients with eGFR ≤30 mL/min/1.73 m2, metformin should be withheld at the time of the contrast infusion and for 48 hours after the procedure