Acute Kidney Injury

Question 1

Fluid balance via kidneys, which 3 actions?

Answer 1

Diuresis/Natriuesis

Anti-diuresis

Question 2

out of 42 litres, how much is intracellullar, interstitial, and IV?

Answer 2

intracellullar: 30L
interstitial: 9L
IV: 3L

Question 3

creatinine is?

Answer 3

byproduct of muscle breakdown

Question 4

Urea from?

Answer 4

byproduct of protein breakdown

Question 5

2 hormones from Kidneys?

Answer 5

1,25 OH Vit. D activation

EPO

Question 6

kidney disease: 2 things can disrupt Na/H20 balance:

Answer 6

1. can’t excrete a fluid load

2. can’t conserve Na of H20

Question 7

Main feature of AKI?

Answer 7

sudden loss and usually reversible

Question 8

what happens to creatinine as GFR falls

Answer 8

creatinine rises

Question 9

Pre-renal causes of AKI?

Answer 9

drop in BP

drop in flow to kidneys

Question 10

intra-renal causes of AKI?

Answer 10

inflamm
drugs
ABx
Contrast

Question 11

post-renal causes of AKI?

Answer 11

obstruction:
stones
bladder
prostate
tumour
injury

Question 12

Prerenal adaptive repsonse to low perfusions is? When is it maladaptive?

Answer 12

RAAS

excessive SNS and RAS = ischaemic injury

Question 13

example of 3rd space losses in hypovolaemia?

Answer 13

ascites

Question 14

how long for tubules to recover from ATN?

Answer 14

10-14 days

Question 15

4 places in intrinsic AKI that can be damaged?

Answer 15

1. Tubules (common ischaemia)
2. Interstitial nephritis (common, drugs, infection, )
3. glomeruli (uncommon, good-pastures)
4. Vascular (uncommon, emboli thrombosis)

Question 16

cause of an autoimmune interstitial nephritis?

Answer 16

sarcoidosis

Question 17

do you have to have low urine with ATN? e.g..?

Answer 17

Nope, Aminoglycosides cause injury but still loss of urine

Question 18

ATN happens where? which cell?

Answer 18

Tubular endothelial cell death

Question 19

what needs to happen to cause post-renal AKI?

Answer 19

bilateral kidney involvement

Question 20

recovery of ATN takes?

Answer 20

2-6 weeks

Question 21

what are 2 big clues to suggest that i’s chronic kidney injury and not acute?

Answer 21

1. comorbidities: DM, HTN, age, Vascular disease

2. small echogenic kidneys

Question 22

Pre-renal AKI sodium and osmolarity compared to ATN?

Answer 22

osmolarity: >500
sodium: <20

Question 23

ATN sodium and osmolarity compared to Pre-renal?

Answer 23

osmolarity: 40

Can’t concentrate

Question 24

what are the 3 key assessments in clinical assessment of AKI?

Answer 24

Volume Status
Urine studies
Renal U/S

Question 25

what change in creatinine/oliguria should make you suspect AKI?

Answer 25

1.5x increase of creatinine from recent baseline

6 hours of oliguria

Question 26

Causes of AKI? (STOP)

Answer 26

Sepsis/hypoperfusion
Toxicity (drugs/contrast)
Obstruction
Parenchymal disease (GN, myeloma)

Question 27

oliguric is defined as?

Answer 27

<400ml/24hr

Question 28

anuric is defined as?

Answer 28

<100ml/24hr