classification of renal disease and AKI Flashcards
what are the three classifications of renal disease
pre-renal
intrinsic
post-renal
what are the pre-renal causes of kidney failure
reduced renal perfusion
what can cause reduced renal perfusion
hypovolaemia
reduced cardiac output
infections
liver disease
certain medications
what medicines can caused reduced renal perfusion
ACEi
NSAID - constrict afferent arteriole
ciclosporin
tacrolimus
diuretics
laxative abuse - D&V
why are ACEi/ARB renoprotective in the long term
reduces pressure in efferent arteriole
what are the intrinsic causes of renal damage
renal tissue damage
secondary to reduced renal perfusion
how can reduced renal perfusion lead to intrinsic kidney damage
nephropathy
interstitial nephritis
hypertension
infection
nephrotoxicity
what causes post renal renal failure
obstruction on urinary flow
- stones
- stricture
- nephrotoxicity
what else, other than cause can be used to classify renal disease
reversibility
what is AKI
acute kidney injury - rapid decline in someone’s levels of kidney function - 90% mortality if not treated
how is AKI diagnosed
serum cr rises by >26.5umol/l in 48hrs or x1.5 baseline in 7 days
what are the stages for AKI
st 1. 1.5-1.9x baseline creatinine
st 2. 2-2.9x baseline creatinine
st 3. 3+ x baseline creatinine
what are the risk factors for AKI
diabetes
CKD
previous AKI
hepatic disease
congestive cardiac failure
>65y/o
what are the causes of AKI
pre-renal is the most common cause - reduced profusion
how can AKI be prevented
avoid triple whammy - ACEi/ARB, NSAID, diuretics
monitor
follow sick day rules
what are the first signs of AKI
volume depletion
- dehydration/thirst
- fluid loss
- oliguria
- tachycardia
- hypotension
what are the later signs of AKI if left untreated
volume overload
- oedema
- sweating
- SOB
- increased orthopnoea
what are the 3 steps to managing AKI
- identify cause
- restore and maintain renal function
- treat cause
how is renal function restored and maintained in AKI
- 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
what other treatments may need to be given in AKI
- abx
- electrolyte correction - hyperkalaemia
how is hyperkalaemia treated
local guidelines
calcium gluconate 10% IV to protect heart
rapid acting insulin in glucose
nebulised salbutamol
what are the symptoms of hyperkalaemia
> 6.5 mmol/L - weakness, ECG changes, v fib, cardiac arrest
6 mmol/L should be urgently treated in AKI patients
