Acute Kidney Injury Flashcards
what is AKI
abrupt and rapid (<48 hours) reduction in kidney function
what findings define AKI (3)
increase in serum creatinine >26.4 micromol/l OR increased creatinine >50% +/- reduced UO (<0.5ml/kg.hr)
what is AKI usually secondary to
circulatory dysfunction
what are some risk factors for AKI (8)
elderly, CDK, diabetes, CF, liver disease, peripheral vascular disease, previous AKI, exposure
what elements of exposure can cause AKI
hypotension, hypovolaemia, hypothermia, deteriorating NEWS
what are symptoms of AKI (7)
anorexia, weight loss, fatigue, NV, itch, sore throat, fluid overload: oedema/ SOB
what signs of AKI are there (5)
oedema, effusions, uraemia –> itch, oliguria, eosinophilia
what investigations are done for AKI
U+E’s (creatinine +urea), GFR, FBC, USS, ECG
why is it important to do in ECG in AKI
check for hyperkalaemia
what treatment can be given for AKI
fluid resuss, treat underlying, dialysis if indicated
what are urgent indications for haemodialysis (4)
hyperkalaemia, severe acidosis, fluid overload, urea >40
what level of potassium indicated hyperkalaemia
normal 3.5-5 // hyperK = >5.5 // life threatening >6.5
what are the 3 general causes for AKI
pre-renal (functional), renal (structural) and post-renal (obstruction)
which cause of AKI is most common
pre-renal
what are the 3 main causes of pre-renal AKI
hypovolaemia, hypotension, renal hypo-perfusion
what role does hydrostatic pressure have in pre-renal AKI
reduced hydrostatic pressure –> reduced GFR –> reduced creatinine excretion + UO
what can cause hypovolaemia
haemorrhage, D+V, burns
what can cause hypotension
cardiogenic shock, reduced CO, sepsis, anaphylaxis
what causes renal hypoperfusion
common with renal artery stenosis: NSAIDs, ACEi, hepatorenal syndromes
what is acute tubular necrosis
untreated prerenal AKI leads to ischaemia
how do you treat pre-renal AKI
underlying and fluids
what are the 4 main causes of intrarenal AKIs
vascular, glomerular, interstitial nephritis and tubular injury
what can cause vascular intrarenal AKI
vasculitis, renovascular disease
what can cause glomerular intrarenal AKI
glomerulonephritis eg nephritic syndrome
what can cause interstitial nephritis intrarenal AKI
drugs (NSAIDs, PPIs), infection, systemic (sarcoidosis)
what can cause tubular injury intrarenal AKI
ischaemia –> acute tubular necrosis, drugs (gent)
how does obstruction cause post renal AKI
back pressure which increases osmotic pressure in glomerulus so less fluid is filtered
what is hydronephrosis
widening of the ureters
what can cause post-renal AKIs
stones, cancer, strictures, extrinsic pressure
how do you treat post-renal AKIs
relieve obstruction eg catheter
