Acute Kidney Injury Flashcards
Fluid balance via kidneys, which 3 actions?
Diuresis/Natriuesis
Anti-diuresis
out of 42 litres, how much is intracellullar, interstitial, and IV?
intracellullar: 30L
interstitial: 9L
IV: 3L
creatinine is?
byproduct of muscle breakdown
Urea from?
byproduct of protein breakdown
2 hormones from Kidneys?
1,25 OH Vit. D activation
EPO
kidney disease: 2 things can disrupt Na/H20 balance:
- can’t excrete a fluid load
2. can’t conserve Na of H20
Main feature of AKI?
sudden loss and usually reversible
what happens to creatinine as GFR falls
creatinine rises
Pre-renal causes of AKI?
drop in BP
drop in flow to kidneys
intra-renal causes of AKI?
inflamm
drugs
ABx
Contrast
post-renal causes of AKI?
obstruction: stones bladder prostate tumour injury
Prerenal adaptive repsonse to low perfusions is? When is it maladaptive?
RAAS
excessive SNS and RAS = ischaemic injury
example of 3rd space losses in hypovolaemia?
ascites
how long for tubules to recover from ATN?
10-14 days
4 places in intrinsic AKI that can be damaged?
- Tubules (common ischaemia)
- Interstitial nephritis (common, drugs, infection, )
- glomeruli (uncommon, good-pastures)
- Vascular (uncommon, emboli thrombosis)
cause of an autoimmune interstitial nephritis?
sarcoidosis
do you have to have low urine with ATN? e.g..?
Nope, Aminoglycosides cause injury but still loss of urine
ATN happens where? which cell?
Tubular endothelial cell death
what needs to happen to cause post-renal AKI?
bilateral kidney involvement
recovery of ATN takes?
2-6 weeks
what are 2 big clues to suggest that i’s chronic kidney injury and not acute?
- comorbidities: DM, HTN, age, Vascular disease
2. small echogenic kidneys
Pre-renal AKI sodium and osmolarity compared to ATN?
osmolarity: >500
sodium: <20
ATN sodium and osmolarity compared to Pre-renal?
osmolarity: 40
Can’t concentrate
what are the 3 key assessments in clinical assessment of AKI?
Volume Status
Urine studies
Renal U/S
