Usf Pa: Acute Renal Failure

Front 1

What are the definitions of acute renal failure?

Back 1

Increase in SCr ≥0.5mg/dL or decrease in GFR ≥25% in pts with previously normal kidney fnxn OR increase of ≥1mg/dL SCr in pts with Chronic Kidney Disease
OR
UO <0.5mL/kg/hr ≥6hrs

Front 2

What are the complications of acute renal failure?

Back 2

Fluid overload, Acid-Base abnormalities, Electrolyte abnormalities

Front 3

What is the definition of anuric?

Back 3

Urine Output <50mL per 24hrs

Front 4

What is the definition of oliguric?

Back 4

Urine Output 50-500 mL per 24hrs

Front 5

What is the definition of nonoliguric?

Back 5

Urine Output >500mL per 24hrs

Front 6

ARF patients in which urine output class have the best outcomes and least volume overload issues?

Back 6

Nonoliguric

Front 7

What are the different classifications of ARF

Back 7

Community-Acquired, Hospital-Acquired, ICU-Acquired

Front 8

Describe Community-Acquired ARF

Back 8

Generally high survival rate,
Result of single insult to kidney, Generally reversible

Front 9

Describe Hospital-Acquired ARF

Back 9

2-5% incidence, Moderate survival rate of 30-50%,
Result of single or multiple insults to kidney, Can be reversible

Front 10

Describe ICU-Acquired ARF

Back 10

High incidence (6-23%)
Multifocal insult to kidney
Poorly reversible

Front 11

What are the Risk Factors for ARF?

Back 11

Volume Depletion, Preexisting Kidney Disease, Nephrotoxic Medications, Urinary Obstruction

Front 12

What are causes of volume depletion (a risk factor for ARF)?

Back 12

Vomiting, Diarrhea, Dehydration, Poor fluid intake, Fever, Diuretics, CHF

Front 13

Describe Pre-renal ARF

Back 13

ARF associated with conditions that decrease renal blood flow and perfusion

Front 14

What are some causes of decreased renal blood flow and perfusion?

Back 14

Hypovolemia, impaired cardiac function, trauma

Front 15

Describe Intrarenal ARF

Back 15

Acute tubular necrosis—Tubular degeneration caused by ischemia or toxic agents

Front 16

What are potential causes of Intrarenal ARF

Back 16

Severe burn injury, hemorrhage (especially post-op), bacteremic shock (gram – endotoxins), crush injury, surgery, analgesic abuse, drugs (AGly, Amphotericin B, cyclosporine, tacrolimus, radiocontrast dye, ACEI’s, NSAID’s, cisplatin, FQ’s, sulfonamides)

Front 17

Describe Post-renal ARF

Back 17

It's generally a result of urinary obstruction and patients are often oliguric

Front 18

What are potential causes of urinary obstruction?

Back 18

Hyperparathyroidism, milk alkali syndrome (over-abundance of Ca+ in diet), hypervitaminosis D, calcium stones, uric acid stones, BPH

Front 19

What is the frequency of drug-induced renal damage?

Back 19

It accounts for 7% of all drug toxicities and 18-27% of ARF in hospitals

Front 20

What puts kidneys at risk for toxicity?

Back 20

High exposure to toxin/drug, Autoregulation, Specialized blood flow through the glomerulus, Intrakidney Drug Metabolism, Tubular transport processes, Concentration of solutes/toxins in tubules

Front 21

What is the mechanism behind aminoglycoside induced ARF?

Back 21

Acute Tubular Necrosis

Front 22

How would patients with aminoglycoside induced ARF present?

Back 22

Gradual rise in SCr and decreased GFR 6-10 days after treatment initiation, Nonoliguric, Potential K+ and Mg wasting

Front 23

What are the risk factors for aminoglycoside induced ARF?

Back 23

Dosing (prolonged treatment, trough >2mg/L, previous treatment), concurrent nephrotoxins, pre-existing kidney disease, elderly, shock, gram negative, hepatic disease, dehydration, electrolyte deficiencies, poor nutrition

Front 24

How can aminoglycoside ARF e prevented?

Back 24

Avoid aminoglycoside use in high risk patients, maintain hydration, limite total aminoglycoside dose, use extended interval dosing, avoid other nephrotoxins

Front 25

How does radiocontrast media IV contrast cause ARF?

Back 25

Acute tubular necrosis

Front 26

How do patients present with radiocontrast induced ARF?

Back 26

Initial transient osmotic diuresis followed by proteinuria, progression to oliguria in 50% of patients (some will need dialysis), SCr increase that peaks after 2-5 days

Front 27

What are the risk factors for radiocontrast induced ARF?

Back 27

Hypotension, DM, Decreased kidney blood flow, Anemia, Prexisting kidney disease, Over age 75, Other nephrotoxins

Front 28

How can radiocontrast induced ARF be prevented?

Back 28

Avoid high risk patients, Maintain hydration, NaHCO3 supplementation prior to administration, avoid other nephrotoxins, mucomyst

Front 29

How do Cisplatin and Carboplatin cause ARF?

Back 29

Acute Tubular necrosis

Front 30

How do patients with Cisplatin and Carboplatin induced ARF present?

Back 30

SCr peaks 10-12 days after treatment initiation (May continue to rise w/subsequent chemo cycles),
Mg wasting (common),
Hypokalemia, hypocalcemia,
Can result in irreversible renal damage

Front 31

What are risk factors for Cisplatin, Carboplatin induced ARF?

Back 31

Multiple courses of cisplatin,
Age (elderly),
Dehydration,
Concurrent nephrotoxins,
Kidney irradiation,
EtOH abuse

Front 32

How can Cisplatin, Carboplatin induced ARF be prevented?

Back 32

Avoid concurrent nephrotoxins,
Aggressive IV hydration within 24hrs of high-dose cisplatin or carboplatin

Front 33

How does Amphotericin B induce ARF?

Back 33

Acute Tubular necrosis

Front 34

How do patients with Amphotericin B induced ARF present?

Back 34

SCr increase & GFR decrease,
Electrolyte wasting (may need significant K+ & Mag supplements)

Front 35

What are the risk factors for Amphotericin B induced ARF?

Back 35

Pre-existing Kidney Disease,
High daily doses,
Cumulative doses of 4gm or more (80% risk),
Concurrent nephrotoxins,
Diuretic use,
Rapid infusion of drug

Front 36

How can Amphotericin B induced ARF be prevented?

Back 36

Avoid other nephrotoxins,
Limit total cumulative dose,
IV hydration w/>1L NS prior to each dose,
Use liposomal AmpB if possible

Front 37

How do ACEIs and ARBs cause ARF?

Back 37

Hemodynamically-mediated renal failure

Front 38

How do patients with ACEI and ARB induced ARF present?

Back 38

SCr can rise by up to 30% w/in 2-5 days of therapy initiation, SCr changes stabilize in 2-3wks, Often reversible after drug D/C’d

Front 39

What are risk factors ACEI and ARB induced ARF?

Back 39

Pre-existing KD, Bilateral renal artery stenosis, Decreased kidney blood flow (CHF, cirrhosis, etc.)

Front 40

How can ACEI and ARB induced ARF be prevented?

Back 40

Avoid other nephrotoxins,
Initiate tx w/low doses of short-acting agents & gradually titrate up,
Switch to long-acting agents once tolerance established,
Monitor SCr qday for inpatients (qwk for outpatients),
Avoid concomitant use of diuretics during initiation of therapy if possible

Front 41

How do NSAIDs induce ARF?

Back 41

Hemodynamically-mediated renal damage

Front 42

How do patients with NSAID induced ARF present?

Back 42

Can occur w/in days of tx initiation, Low urine volume
Decreased Na, Increased BUN, SCr, and K+, Edema

Front 43

What are risk factors for NSAID induced ARF?

Back 43

Pre-existing KD, SLE, High plasma renin activity (CHF and hepatic dz), Diuretic tx,
Elderly

Front 44

How can NSAID induced ARF be prevented?

Back 44

Avoid other nephrotoxins,
Use other non-NSAID tx if possible, Sulindac may have less risk of renal damage than other NSAID’s

Front 45

What are the different ways to measure renal function?

Back 45

GFR (dont use this to dose though), 24 urine CrCl, Calculated CrCl

Front 46

What are factors that affect SCr?

Back 46

Age, sex, weight, muscle mass

Front 47

When is 24 urine CrCl the best measure?

Back 47

In patients with low muscle mass, amputees, or when you are determining the need for dialysis

Front 48

What is the Crockoft-Gault CrCl formula for females?

Back 48

[(140-age) x IBW] / [SCr x 72] x 0.85

Front 49

How can renal failure be prevented?

Back 49

Avoid nephrotoxic agents, Ensure adequate hydration (0.9% NaCl preferred IVF),
Patient education,
Pre-meds for IV radiocontrast agents,
Acetylcysteine (Mucomyst),
Tight glycemic control if in ICU (80-110mg/dL, insulin therapy can reduce incidence by 41%,
decrease in risk of infxn, ventilation requirements/days on vent, LOS)

Front 50

How can Pre-renal azotremia be treated/what is the treatment goal?

Back 50

Goal: Correct hemodynamics
Treatment: Blood pressure mgmt,Blood products, if needed, NS for volume depletion

Front 51

How can Post-renal Azotemia be treated/what is the treatment goal?

Back 51

Goal: Relieve obstruction
Treatment: Non-pharmacologic measures—surgery, etc

Front 52

How can renal failure be treated (intrinsic)?

Back 52

Remove causative agent, Avoid nephrotoxic drugs, Fluid mgmt,Restrict dietary protein (<0.5mg/kg/day),
NaHCO3— Maintain HCO3 >15mEq/L & arterial pH >7.2,
Dialysis for renal replacement therapy if needed (HD or PD)

Front 53

How should fluids be managed during renal failure (intrinsic)?

Back 53

Diuretics only if hypervolemic, euvolemic or oliguric.
IV loops,
Intermittent IVP or continuous infusion,
Combo w/thiazides may decrease risk of resistance to loops

Front 54

What is the mechanism of action of Acetylcysteine (Mucomyst)?

Back 54

Antioxidant properties; Prevents direct oxidative tissue damage, minimizing radiocontrast-related renal dysfnxn

Front 55

What are the adverse effects of Acetylcystein (Mucomyst)?

Back 55

Dizziness, N/V, Well-tolerated

Front 56

What are the kinetics of Acetylcystein (Mucomyst)?

Back 56

Administered orally (600mg po bid x 2 days, beginning day before procedure)
Absorption: Peaks 1-2hrs

Front 57

How should Acetylcystein (Mucomyst) be administered?

Back 57

Recommended to dilute it in cola or juice