classification of renal disease and AKI

Question 1

what are the three classifications of renal disease

Answer 1

pre-renal
intrinsic
post-renal

Question 2

what are the pre-renal causes of kidney failure

Answer 2

reduced renal perfusion

Question 3

what can cause reduced renal perfusion

Answer 3

hypovolaemia
reduced cardiac output
infections
liver disease
certain medications

Question 4

what medicines can caused reduced renal perfusion

Answer 4

ACEi
NSAID - constrict afferent arteriole
ciclosporin
tacrolimus
diuretics
laxative abuse - D&V

Question 5

why are ACEi/ARB renoprotective in the long term

Answer 5

reduces pressure in efferent arteriole

Question 6

what are the intrinsic causes of renal damage

Answer 6

renal tissue damage
secondary to reduced renal perfusion

Question 7

how can reduced renal perfusion lead to intrinsic kidney damage

Answer 7

nephropathy
interstitial nephritis
hypertension
infection
nephrotoxicity

Question 8

what causes post renal renal failure

Answer 8

obstruction on urinary flow
- stones
- stricture
- nephrotoxicity

Question 9

what else, other than cause can be used to classify renal disease

Answer 9

reversibility

Question 10

what is AKI

Answer 10

acute kidney injury - rapid decline in someone’s levels of kidney function - 90% mortality if not treated

Question 11

how is AKI diagnosed

Answer 11

serum cr rises by >26.5umol/l in 48hrs or x1.5 baseline in 7 days

Question 12

what are the stages for AKI

Answer 12

st 1. 1.5-1.9x baseline creatinine
st 2. 2-2.9x baseline creatinine
st 3. 3+ x baseline creatinine

Question 13

what are the risk factors for AKI

Answer 13

diabetes
CKD
previous AKI
hepatic disease
congestive cardiac failure
>65y/o

Question 14

what are the causes of AKI

Answer 14

pre-renal is the most common cause - reduced profusion

Question 15

how can AKI be prevented

Answer 15

avoid triple whammy - ACEi/ARB, NSAID, diuretics
monitor
follow sick day rules

Question 16

what are the first signs of AKI

Answer 16

volume depletion
- dehydration/thirst
- fluid loss
- oliguria
- tachycardia
- hypotension

Question 17

what are the later signs of AKI if left untreated

Answer 17

volume overload
- oedema
- sweating
- SOB
- increased orthopnoea

Question 18

what are the 3 steps to managing AKI

Answer 18

1. identify cause
2. restore and maintain renal function
3. treat cause

Question 19

how is renal function restored and maintained in AKI

Answer 19

• in vol depletion
  early and aggressive fluid resus, monitor input and output - dialysis may be used
• in vol overload
  loop diuretics- furosemide 1-2g/24 hrs only if no issue with renal perfusion
  dopamine - 2mcg/kg/min

Question 20

what other treatments may need to be given in AKI

Answer 20

• abx
• electrolyte correction - hyperkalaemia

Question 21

how is hyperkalaemia treated

Answer 21

local guidelines
calcium gluconate 10% IV to protect heart
rapid acting insulin in glucose
nebulised salbutamol

Question 22

what are the symptoms of hyperkalaemia

Answer 22

> 6.5 mmol/L - weakness, ECG changes, v fib, cardiac arrest
6 mmol/L should be urgently treated in AKI patients