Acute kidney injury Flashcards
Acute kidney injury is the abrupt decline in ____manifested by an acute rise in __________
Acute kidney injury is the abrupt decline in GFR manifested by an acute rise in serum creatinine
true or false: high mortality rate in AKI
true: 21%
mesurement of GFR
- inulin is the gold standard since it is freely filtered and not secreted or reabsorbed but…
- creatinine is more convenient but while it is freely filtered and not reabsorbed it is s secreted and thus overestimates GFR
low mol weight protein released by all nucleated cells at constant rate
cystatin C
Cystatin C is affected by
thyroid dz
oliguric AKI
low urine output portend worse prognosis
non-oliguric AKI
nml urine output despite inadequate clearance– may have severely reduced GFR with well-maintained urine output
Pre-renal AKI
perfusion related
intra-renal AKI
intrinsic
post-renal
obstructive AKI
risk factors for AKI
- advanced age
- preexisting chronic kidney disease
- DM
- underlying heart or liver disease
in perfuison related AKI we see a decline in kidney perfusion due to a __________
true intravascular volume depletion
decreased kidney perfusion can be caused by
- decreased effective plasma volume such as in hepatic failure, sepsis
- renal artery stenosis
- hypovolemia such by diuretics, trauma, diarrhea or vomiting
- decreased cardiac output like CHF or massive PE
- interference with autoregulation
what exacerbates reduced kidney perfusion in patients with volume depletion
NSAIDs or ACE inhibitors
As kidney perfusion decreases, GFR is maintained via autoregulation involving _______ (potent efferent ________) and __________(__________the afferent arteriole and ameliorate the effect of AII)
As kidney perfusion decreases, GFR is maintained via autoregulation involving angiotensin II (potent efferent vasoconstrictor) and prostaglandins (vasodilate the afferent arteriole and ameliorate the effect of AII)
is a high or low FeNa (<1%) consistent with perfusion-related AKI
low
obstructive causes of AKI
- obstruction of bladder outlet
- nephrolithiasis
- retroperitoneal fibrosis
- intratubular obstruction