Acute Kidney Injury

Question 1

what is AKI

Answer 1

abrupt and rapid (<48 hours) reduction in kidney function

Question 2

what findings define AKI (3)

Answer 2

increase in serum creatinine >26.4 micromol/l OR increased creatinine >50% +/- reduced UO (<0.5ml/kg.hr)

Question 3

what is AKI usually secondary to

Answer 3

circulatory dysfunction

Question 4

what are some risk factors for AKI (8)

Answer 4

elderly, CDK, diabetes, CF, liver disease, peripheral vascular disease, previous AKI, exposure

Question 5

what elements of exposure can cause AKI

Answer 5

hypotension, hypovolaemia, hypothermia, deteriorating NEWS

Question 6

what are symptoms of AKI (7)

Answer 6

anorexia, weight loss, fatigue, NV, itch, sore throat, fluid overload: oedema/ SOB

Question 7

what signs of AKI are there (5)

Answer 7

oedema, effusions, uraemia –> itch, oliguria, eosinophilia

Question 8

what investigations are done for AKI

Answer 8

U+E’s (creatinine +urea), GFR, FBC, USS, ECG

Question 9

why is it important to do in ECG in AKI

Answer 9

check for hyperkalaemia

Question 10

what treatment can be given for AKI

Answer 10

fluid resuss, treat underlying, dialysis if indicated

Question 11

what are urgent indications for haemodialysis (4)

Answer 11

hyperkalaemia, severe acidosis, fluid overload, urea >40

Question 12

what level of potassium indicated hyperkalaemia

Answer 12

normal 3.5-5 // hyperK = >5.5 // life threatening >6.5

Question 13

what are the 3 general causes for AKI

Answer 13

pre-renal (functional), renal (structural) and post-renal (obstruction)

Question 14

which cause of AKI is most common

Answer 14

pre-renal

Question 15

what are the 3 main causes of pre-renal AKI

Answer 15

hypovolaemia, hypotension, renal hypo-perfusion

Question 16

what role does hydrostatic pressure have in pre-renal AKI

Answer 16

reduced hydrostatic pressure –> reduced GFR –> reduced creatinine excretion + UO

Question 17

what can cause hypovolaemia

Answer 17

haemorrhage, D+V, burns

Question 18

what can cause hypotension

Answer 18

cardiogenic shock, reduced CO, sepsis, anaphylaxis

Question 19

what causes renal hypoperfusion

Answer 19

common with renal artery stenosis: NSAIDs, ACEi, hepatorenal syndromes

Question 20

what is acute tubular necrosis

Answer 20

untreated prerenal AKI leads to ischaemia

Question 21

how do you treat pre-renal AKI

Answer 21

underlying and fluids

Question 22

what are the 4 main causes of intrarenal AKIs

Answer 22

vascular, glomerular, interstitial nephritis and tubular injury

Question 23

what can cause vascular intrarenal AKI

Answer 23

vasculitis, renovascular disease

Question 24

what can cause glomerular intrarenal AKI

Answer 24

glomerulonephritis eg nephritic syndrome

Question 25

what can cause interstitial nephritis intrarenal AKI

Answer 25

drugs (NSAIDs, PPIs), infection, systemic (sarcoidosis)

Question 26

what can cause tubular injury intrarenal AKI

Answer 26

ischaemia –> acute tubular necrosis, drugs (gent)

Question 27

how does obstruction cause post renal AKI

Answer 27

back pressure which increases osmotic pressure in glomerulus so less fluid is filtered

Question 28

what is hydronephrosis

Answer 28

widening of the ureters

Question 29

what can cause post-renal AKIs

Answer 29

stones, cancer, strictures, extrinsic pressure

Question 30

how do you treat post-renal AKIs

Answer 30

relieve obstruction eg catheter