Acute Renal Failure

Question 1

What is the definition of Acute Renal Failure?

Answer 1

Rapid decrease in GFR, resulting in Azotemia (waste build up in the blood).

Question 2

Which lab values are increased in ARF?

Answer 2

BUN, Creatinin, Potassium, Magnesium, Phosphorus, & FESNa > 2% (Fractional excretion of Na).

Question 3

Which lab values are decreased in ARF?

Answer 3

Hgb, hct, Na, Ca, specific gravity & albumin.

Question 4

What’s the normal value of specific gravity?

Answer 4

1.010-1.030

Question 5

What acid-base imbalance will be seen?

Answer 5

Metabolic acidosis d/t renal failure or DKA.

Question 6

In ATN, what happens to the Na concentration in the urine?

Answer 6

Increases above 40 mEq.

Question 7

What is normal GFR per minute and per day?

Answer 7

125mL/min

180L/day

Question 8

GFR is measures by creatinine clearance. What is the normal value?

Answer 8

120-130mL/min

Question 9

What are the AEIOU complications of ARF?

Answer 9

Acid/base problems (metabolic acidosis)
Electrolyte problems (Increased K, decreased Ca & Na)
Intoxications (meds–>intra-renal)
Overload of fluids (d/t blockages–>post-renal)
Uremic s/s (uremic frost, bruising, more prone to GI bleeds d/t increased ammonia levels).

Question 10

What are the causes of Pre-Renal ARF?

Answer 10

Hypovolemia, cardiovascular failure/shock (25% of C.O comes from kidneys), & burns.

Question 11

What is the tx of Pre-Renal ARF?

Answer 11

Fluids & Diuretics

Question 12

What are the causes of Intra-Renal ARF?

Answer 12

ATN, Infection and nephrotoxic medications

Question 13

What is the tx of Pre-Renal ARF?

Answer 13

Hemodialysis

Question 14

What are the causes of Post-Renal ARF?

Answer 14

Blockages/Calculi

Question 15

What is the tx of Post-Renal ARF?

Answer 15

Surgery

Question 16

There are 4 phases of ATN. Name them.

Answer 16

Onset, Oliguric/Anuric, Diuretic, & Recovery.

Question 17

How long does each phase of ATN last?

Answer 17

Onset: hrs-days
Olig/Anur: Anur: 5-8 days, Olig: 10-16 days
Diuretic: 7-14 days
Recovery: Weeks-months

Question 18

How much fluid should the patient be losing in the diuretic phase?

Answer 18

2-4L/day, or at least 400ml/24hrs

Question 19

In what phase of ATN do the kidneys lose ability to concentrate urine?

Answer 19

Diuretic b/c they’re filtering fluid very quickly.

Question 20

What are the 4 types of Renal Replacement Therapy?

Answer 20

Hemodialysis, Peritoneal Dialysis, CVVH (Continuous Venovenous Hemofiltration) & CVVHD (Continuos Venovenous Hemodialysis).

Question 21

What are the indications & advantages of Peritoneal Dialysis?

Answer 21

Indicated for CHRONIC kidney failure, HD unstable or bleeding patients when vascular access is difficult.
Advantages: ambulatory, slow, no anticoagulants needed.

Question 22

What are the disadvantages of Peritoneal Dialysis?

Answer 22

Less predictable fluid removal b/c it drains by gravity with implanted catheter. May cause peritonitis r/t catheter infxn, needs to sleep sitting up (drains by gravity), increased risk of hyperglycemia, must empty colon first.

Question 23

When is a temporary dialysis catheter indicated? Where is it placed?

Answer 23

Indicated for emergency HD or new onset of ARF or failed access.
Can be placed in IJ, Subclavian, or Femoral artery.

Question 24

When is a tunneled catheter indicated?

Answer 24

For chronic kidney disease patients awaiting permanent access, so it can be for long-term use.

Question 25

What the difference between an AV fistula and an AV graft?

Answer 25

A fistula is when the artery and vein is surgically connected. It needs time to mature. Nrs must assess for bruits & thrills.
A graft is made from synthetic material to create the connection between the artery and vein. No maturation time needed.
Neither of these access types are allowed BP or blood draws.

Question 26

How does continuous venovenous hemofiltration (CVVH) work?

Answer 26

Removes solutes & fluid via convection (“Solvent drag”),
large amounts of fluid can be removed; increased pressure through the filter. It runs over 24hrs and is indicated for diuretic resistant fluid overloaded patients.