Acute Renal Failure

Question 1

acute renal failure

Answer 1

inability to kidney to carry out Fx (ultrabsorption & reabsorption)

• l/o renal Fx –> dec urine output –> azotemia & fluid-lyte imbal
• Typically reversible but can progress to chronic renal failure

Question 2

GFR and acute renal failure

Answer 2

GFR may dec within hours or days of acute renal failure

Question 3

GFR requirements

Answer 3

• urine vol

- creatinine in blood + urine

Question 4

oliguria output

Answer 4

100-400mL/day ~

Question 5

anuria output

Answer 5

<100mL/day

Question 6

etiology

Answer 6

• prerenal: Ischemic/circulatory problem prevents proper perfusion to kidney (ex. hypotension or hypovolemia)
• intrarenal: Glomerular nephritis (problem within kidney)
• postrenal: Obstr prevents urine to flow out of kidney (ex. BPH)

Question 7

80-90% of ARF is which type of renal failure

Answer 7

prerenal or intrarenal

Question 8

patho of prerenal

Answer 8

Ex. Hemorrhage –> lose blood vol –> inadequate perf to glomerular –> ischemia & ischemic damage –> dec filtration

Question 9

patho of intrarenal

Answer 9

Acute tubular necrosis (ATN) –> nephrotoxic drugs, intratubular obstr (days or wks to happen)

Question 10

patho of post renal

Answer 10

Ex. BPH –> hydronephrosis –> ARF

- obstr to urine flow

Question 11

3 phases of ARF

Answer 11

1) initiating phase
2) maintenance phase
3) recovery phase

Question 12

initiating phase duration

Answer 12

Lasts from precipitating event to the time mnfts appear

- hours to days

Question 13

maintenance phase characteristics

Answer 13

• dec GFR
• oliguria
• azotemia
• fluid retention

Question 14

cmplx from fluid retention

Answer 14

• HTN
• edema
• pulmonary congestion

Question 15

recovery phase

Answer 15

Gradual inc in GFR as tissue repaired

Question 16

non-oliguric forms of renal failure

Answer 16

Problem detected earlier d/t better screening techniques

Question 17

mnfts

Answer 17

• oliguria or anuria
• fluid-lyte imbal
• azotemia
• proteinuria, hematuria

Question 18

azotemia

Answer 18

buildup of nitrogenous wastes that can impact vital organs (ex. brain)

Question 19

Dx

Answer 19

• renal Fx tests (BUN, GFR, creatinine)
• RIFLE
• creatinine clearance rate to estimate GFR
• new early biomarkers

Question 20

RIFLE

Answer 20

• Risk (of running into renal failure)
• Injury (actual damage in kidney)
• Failure (some kind of renal failure has begun)
• Loss (l/o renal fx, mnfts appear)
• End stage renal disease (kidney shuts off and pt will die)

Question 21

creatinine clearance ratio

Answer 21

Amount of creatinine in blood, urine & amount of urine excreted

Question 22

new early biomarkers example

Answer 22

Interleukin-18

Question 23

Interleukin-18

Answer 23

mediator produced w/ inflm in proximal tubule when there is ischemic damage

• Early indictor of renal failure b/c proximal tubule will be first area to be affected within kidney

Question 24

Tx

Answer 24

• reversible (not self-limiting)
• STAT intervention
• cautious fluid & electrolyte replacement
• diet (adequate proteins)
• dialysis

Question 25

why must you be careful with protein intake with ARF

Answer 25

Protein broken down into ammonia (nitrogenous waste), limiting protein ingestion helps to avoid/dec azotemia

Question 26

types of dialysis

Answer 26

• hemodialysis
• peritoneal dialysis
• intermittent dialysis
• CRRT (continuous oral replacement therapy)

Question 27

hemodialysis

Answer 27

blood filtered externally from body through dialyser (artificial kidney)

Question 28

peritoneal dialysis

Answer 28

dialysate introduced into peritoneum, which acts as semi-permeable membrane that wastes filtered through

Question 29

intermittent dialysis duration

Answer 29

over few hours

Question 30

CRRT (continuous oral replacement therapy)

Answer 30

• slower than intermittent

- different methods used (convection, diffusion, or both)