Renal phys Flashcards
What are nerve plexus deliver SNS to the kidneys?
Renal and celiac
Does the kidney have PNS innervation?
NO
Where is ammonia produced in the kidney?
PCT and collecting tubule
Which part of the kidney is responsible for maintaining hypertonic medullary interstitium?
Loop of Henle
Which part of the kidney secretes H, K and Ca?
DCT and collecting tubule
What is GFR directly related to?
MAP and efferent arteriole tone
What is GFR inversely related to?
The afferent arteriole tone
What is the equation for GFR?
GFR = 140 - age X body weight in kg/serum creatinine X 72
What is a normal GFR for a man?
120 +/- 25 ml/min
What is a normal GFR for a woman?
95 +/- 20 ml/min
Between what blood pressures in RBF autoregulated?
Between 80-800
What is the Hendersen-Hasselbach equation?
ph = 6.1 + log (HCO3/).03 X PaCO2)
What are the buffers in the body?
Bicarb Ammonia Phosphate Intracellular proteins Hemoglobin
What is a normal anion gap?
7-14 mEq/l
What is the equation for calculating an anion gap?
Na - (Cl + HCO3)
What is a normal PaCO2?
36-44
What is the golden rule for changes in ph based on change in PaCO2?
For every 10 torr change in PaCO2, the ph will change 0.08 unit in the opposite direction
What are the predictors of postop renal failure?
Jaundice LVF Diabetes Advanced age Increased BUN/Cr Cardiac or aortic surgery
What is acute renal failure defined as?
A significant decrease in GFR over 2 weeks or less or inadequate urine output of less than 0.5ml/kg/hr
What is a late sign of renal failure?
Elevated serum creatinine
Does good urine output rule out ARF?
no
How much can GFR be reduced before the labs show it?
50%
What does a FeNa of less than 1 tell us?
The problem is prerenal
What does a FeNa of greater than 3 tell us?
ATN
What is the doubling of creatinine associated with?
A reduction in GFR of 50%
What is the most sensitive test for renal failure?
Creatinine clearance
What are the do the volatile anesthetics do to renal function?
Depress it, decrease urine output, GFR, RBF and electrolyte excretion
Which volatile anesthetic can cause renal failure with low gas flows?
Sevoflurane - makes compound A
Which NMBs can be used in patients with renal failure?
Atracurium, cisatracurium because they undergo Hoffman elimination
What are the indications for dialysis?
Uremic platelet dysfunction uremic symptoms uremic percarditis/tamponade bleeding hypervolemia CHF Severe acidosis Hyperkalemia
