GP 7 / ILA 5 - AKI Flashcards
What are the normal blood values for creatinine and egfr
creatinine male: 64-111
female: 50-98
gfr: 90-120
what is the diagnostic criteria for aki?
rise in creatinine over 26 in 48 hrs.
rise in creatininne over 1.5* baseline
urine output less than 0.5 ml/kg/hr for more than 6 hrs
normal urine output = 1-2 ml/kg/hr
only need to meet 1 criteria
3 major classes of aki
pre renal - reduced renal perfusion = reduced egfr.
intrinsic - intrinsic renal damage
post renal - least common - bph, malignancy
pre renal examples - causes of aki
renal artery stenosis
reduced cardiac output
shock
dehydration
intrinsic examples - causes of aki
acute tubular necrosis
glomerulonephritis , vasculitis, tubular acidosis
nephrotoxins: nsaids
post renal eg’s - aki causes
bph
malignancy
acute tubular necrosis causes
ischaemic or nephrotoxic in nature.
if ischaemic:
inadequate renal perfusion.
pro-inflammatory response with release of cytokines, activate coagulation
celllular injury occurs.
tubular cells limited blood supply and high metabolic demand. damaged cells into lumen - obstructive casts, lower egfr.
polyuric phase happens - recovering tubules cant reabsorb.
once prescribing iv fluids, what improvements would you see in HR and BP?
HR increases as SV decreases.
lower HR and higher BP.
why would diclofenac be CI’d in aki?
its an nsaid - nephrotoxic
reduced renal perfusion and reduced gfr (pre)
can glomerunephritis and intersitital nephritis (renal)
what abnormality would an ecg show in aki patient?
hyperkalemia
absent p , tall tented t , prolonged, pr, wide qrs
mechanism of insulin correcting raised electrolyte level and why dextrose is always given at same time?
insulin drives k+ into cells via na-k ATPase pump
dextrose- makes sure pt doesnt become hypoglycaemic.
define aki
sudden decline in kidney function = rise in serum creatinine and fall in urine output.
risk factors of aki
Age >65
Heart failure
Diabetes
Poor fluid intake
Hypovolaemia
Nephrotoxic meds (NSAID, ACEi)
Contrast medium usage in imaging
Prostate cancer
BPH
Sepsis
Liver disease
pre-renal causes:
Hypoperfusion
Hypovolaemia (bleeding, reduced cardiac output (CHF), cardiogenic shock)
Liver failure (hypoalbuminaemia)
Renal artery blockage/stenosis
ACEi & NSAID
Sepsis causing systemic vasodilation
Dehydration
intra-renal causes of aki
Intrinsic disease of kidney
Acute tubular necrosis
Acute interstitial nephritis (these 2 can be drug induced)
Glomerulonephritis
Small vessel vasculitis
