Kidney Flashcards
azotemia
retention of creatinine
first step in urine formation
glomerular filtration
How are casts shaped?
in the form of the nephron they originate in
Heavy protein and lipiduria
nephrotic syndrome
hematuria and proteinuria
glomerulonephritis
pigmented casts and renal tubular cells
acute tubular necrosis
WBCs, RBCs, and protein
interstitial nehritis or pyelonephritis
how much protein in the urine indicated glomerular origin of disease?
> 1g
Functional proteinuria
<1g
examples of overload proteinuria
bence jones protein, myoglobinuria, hemoglobinuria
increased filtration of proteins, effacement of epithelial cell foot processes
glomerular proteinuria
faulty reabsorption in the proximal tubule
tubular proteinuria
how much protein indicates nephrotic range?
> 3.5g
dx of hematuria
3 red cells per HPF on 2 occasions
normal GFR
150-250 (worry when it hits 60)
What can cause normal or increased GFR?
hyperfiltration, disease at a different site in the nephron, interstitium, or vascular supply
GFR estimation equation
C = (UxV)/P
True or false: creatinine production and excretion are equal in normal states
true
Cockcroft Gault formula
((140-age) x weight)/(Pcr x 72)
What should CrCl be multiplied by in women?
0.85
when is GFR overestimated?
obese, edematous pts
CrCl is most accurate with a BSA of _____
1.73
Where is BUN synthesized?
liver
What underestimates GFR causing an increased BUN?
urea clearance, dehydrated, volume depleted, GI bleed, cell lysis, steroids, increased protein, decreased renal perfusion, renal artery stenosis
Normal BUN:creat
10:1
BUN:creat in someone volume depleted
20:1
What is an accurate depiction of GFR?
avg of the creatinine clearance and urea clearance
absolute contraindications to kidney biopsy
bleeding disorder not corrected, uncontrolled HTN, renal infection, renal neoplasm, hydronephrosis, uncooperative pt
when will creatinine respond to acute renal failure?
when 50% of kidney function is lost
Risk category
Creatinine increased 1.5 times, 0.5 ml of urine for 6 hours
Injury category
Creatinine increase 2 times, 0.5 ml or urine for 12 hours
Failure category
Creatinine increased 3 times or >4mg with an acute increased of 0.5, 0.3ml of urine in 24 hours or anuria for 12 hours
Loss category
loss of kidney function for 4 wks
ESRD category
need for renal transplant therapy for 3 months
MCC of CA-acute renal failure
prerenal
MCC of HA-acute renal failure
ATN
what type of ARF has a higher mortality rate?
Hospital acquired
MCC of death due to ARF
sepsis and cardiopulmonary failure
describe prerenal ARF
volume depletion, vasodilation, tubular and glomerular function are maintained
describe intrinsic ARF
vasoconstriction, decreased renal perfusion
MCC of intrinsic ARF
ATN/AKI
True or false: pstrenal ARF must be bilateral
true
how much CO do the kidneys receive?
25%
causes of prerenal ARF
pancreatitis, CHF, hepatic failure, the usual
Treatment of prerenal ARF
fluids +/- dopamine
causes of intrinsic ARF
Cardiac arrest, sepsis, systemic HOTN or ischemia, rhabdomyolysis, glomerulonephritis, interstitial nephritis, renal artery occlusion, pulmonary-renal syndromes
treatment of intrinsic ARF
furosemide or mannitol (not if anuric) + dopamine
how to dx postrenal ARF
US with doppler
what will a BMP of ARF show?
acidosis and hyperkalemia
How is intrinsic ARF confirmed?
renal biopsy
What type of imaging is used to evaluate ARF
non contrast CT
urine sodium <40, high urine Cr: serum Cr ratio and Serum urea: Serum Cr ratio
prerenal ARF
urine sodium >40
instrinsic ARF
what artery and vein are used for an AV fistula for hemodialysis?
brachiocephalic and radiocephalic
when are AV grafts useful?
when vessels can’t tolerate high flows
What is used for semi-emergent dialysis or when the fistula is maturing?
Hickman tunneled catheter
True or false: a bruit SHOULD be heard over an AV fistula
true
Tx of thrombosis of AV fistula
angioplasty