1) Accurate assessment of renal function relies heavily on what?

2) B.U.N. , the primary source of urea is produced where? 

3) ________ is a byproduct of protein catabolism as amino acids are de-aminated. The liver converts _________ (dangerous compound) to urea.

4) The BUN level is ______a______ related to the break down of protein and _____b_____ related to the GFR. 

5) Is BUN a reliable indicator of GFR?

6)  What is the normal BUN?

1) lab data- The most useful tests are those that are related to GFR

2) Liver

3) Ammonia

4)  a: directly   b: indirectly

5) No not really.  It can be if all other factors remain constant.

6) 10-20 mg/dl

1) When will you see higher values of BUN?

2) What are some other causes of BUN increase?

3) At what value BUN is there "usually" renal impairment?

1) High protein catabolism or decreased GFR state.

2) Reabsorption of large hematomas or high protein diets. 

3) > 50 mg/dl

1) _________ is a product of muscle metabolism (unrelated to enzymatic activity)  Production in most people is relatively constant and is related to muscle mass. 

2) For number 1:  What are the lab values for men?  Women?

1) Creatinine

2) Men- .8 to 1.3 mg/dl

Women- .6 to 1 mg/dl

1) Creatinine levels are ___a____ related to muscle mass and ____b_____ related to GFR.

2) Each time the creatinine doubles there is a ____a_____ reduction in GFR.

1) a: directly

b: indirectly

2) a: 50%

1) How much does GFR decline each decade after age 20? 

2) Because muscle mass declines with age what happens to the creatinine?

3) If creatinine rises in the elderly why should we worry?

4) How long does it take creatinine to equilibrate to GFR?

1) 5% per decade

2) it stays nearly the same!

3) This means large changes (for the worse) in GFR!!!!Aaaahhhhhhhhh!!!!!!!

4) 48-72 hours

1) How can we determine a GFR? (there are like 3 or 4)

2) What is Urinalysis helpful in determining?

1) 24 hour collection,

Can be done with a 2 hour collection

can be calculated from blood creatinine with consideration to factors like: age, race, gender, other

2) Presence of:

Protien

Glucose

Bacteria

WBCs

Snap shot osmolality

Electrolytes

True or False:

1) Pts with renal impairment have decreased sensitivity to barbiturates.

2) pts with renal impairment have increased sensitivity to benzodiazepines

3) Due to the fact that all opioids are metabolized in the liver renal failure has little impact. 

4) Exceptions to #3 include Morphine and fentanyl as they both have active metabolites.

5) Morphine 6 Glucuronide, a metabolite of morphine, can build up and cause seizures.

6) Normerperdine, a metabolite of demerol, causes respiratory depression.

7) Azotemia (excessive levels of creatinine, urea, and ammonia) diminish the pharmacological actions of many anesthetic agents. 

8) NSAID doses should be decreased by 50% in the elderly due to a  reduction in kidney nephron numbers.

1) False. Increased

2) True

3) True

4) False.  Morphine and Demerol have active metabolites

5) False- can continue to cause resp. depression

6) False- causes seizures

7) False.  Azotemia potentiates many agents

8) True

1) For decreased renal function what do we need to consider OR what is a concern with Succs?

2) What are the muscle relaxants of choice for acute renal failure cases?  Why?

1) K+ Levels.  If below 5 meq/l it is usually safe to use succs.  Need to weigh risk to benefit of succs.

2) Cisatracurium (nimbex) and Atracurium (norcuron).  Metabolized through plasma ester hydrolysis (hoffman elimination)

*****Should consider these in cases where hypoperfusion or rhabdomyolysis may be a concern as well********

1) What accounts for 1/2 of ALL patients requiring dialysis?  What type of mortality rate do we see with this?

2) How is acute renal failure classified?

3) Classifications: (due to cause)

___a___ occurs due to hemodynamic or endocrine factors that impair renal perfusion.

____b____ occurs due to tissue damage

____c____ is due to an obstruction

4) Of the above, which one do we impact the most?

1) perioperative acute renal failure.  It is associated with a 50% mortality rate and this hasn't changed in 50 years despite improvement in treatment. 

2) Classified according to cause or based on urine flow rate.

3) a: Prerenal

b: Renal

c: post renal

4) We impact prerenal the most.

Renal Failure Classification according to flow rates:

1) _________ is a flow rate <.5ml /kg/hr in a patient subject to acute stress.  (see handout)

2) ________ is an elevation of BUN and creatinine and is characterized by urine flow rates > 2.5 Liters/day

3) ____________ is a general term used to describe a person in acute renal failure that is still making pee pee but not able to concentrate. patients excrete more than 500 milliliters per day (> 16 oz/day)

1) Oliguric

2) Polyuric

3) NonOliguric

1) ______________ is a rapid deterioration in renal function with the toxic build up of byproducts.

2) Typically: How long does #1 above last?

1) Acute renal failure

2) 2 weeks.  Then it is followed by a diuretic phase.  It can take up to 1 year for renal function to return to normal.

Okay- for the following labs regarding Acute Renal Failure- Stand up grab your crotch- sing out Michael Jackson like- "increased" or "Decreased"

1) Urea, Creatinine, uric acid, phosphate

2) sodium, calcium

3) Potassium

4) Serum Protein

5) Glucose

6) Magnesium/ Phosphorus

1) Increased (hee hee)

2) Decreased (Sham on!)

3) Increased .3 to 3 meq per day (whos bad?)

4) Decreased (hoooooooo!)

5) Increased 

6) Increased

1) Cardiac (2-4% overall.  Higher if LV dysfunction

2) CPB > 2 hours

3) Low cardiac output/ IABP requirement

4) Ruptured AAA

5) Cross clamping of the aorta suprarenally

6) Trauma with severe hypovolemic shock

7) Any case that results in DIC, Sepsis, toxic substances.

8) Use of Dye

9) Toxemia