Clinical Indicators of Renal Disease Flashcards
The hallmark of acute renal failure
oligouria/anuria
Why can’t you just assume oligouria/anuria is ARF?
Could be dehydration, loss of blood
In CRF, inability to concentrate urine is…
an indicator of impending renal failure
Equation for GFR?
(Urine Conc. x Urine Flow) / Plasma Concentration
What is fractional excretion?
Measure of the amount of solute filtered vs amount recovered in urine
What is indicated by a fractional sodium above or below 1?
Above - Inability to concentrate (tubular failure)
Under – Retention of Sodium (activation of RAA)
Prerenal azotemia is marked by…
Some blood filtered, but not enough.
BUN reabsorbed, but Creatinine lost
Causes BUN/Creatinine over 20
Glomerular disease is marked by…
Little blood filtered – neither BUN nor creatinine
Both filtered at a comparable rate, ratio stays below 20
Normal Na levels
135-145
Normal K levels
3.9-5.4
In renal failure, why does Potassium go up?
K retention + metabolic acidosis
In renal failure, why does Phosphate go up?
Lack of filtration/Secretion
Actually triggers the hypocalcemia by complexing with it and precipitating into muscle, joints.
Triggers 2ndary hyperPT –> osteodystrophy
Two primary causes of metabolic acidosis in renal disease
Lack of filtration of organic acids due to decreases in GFR
Tubular loss of bicarb
In metabolic acidosis from loss of bicarb, effect on Cl?
What type of kidney damage might you expect?
Cl- rises to balance
HYPERCHLOREMIC METABOLIC ACIDOSIS
Tubular Disease
In metabolic acidosis triggered by retention of organic acids, effect on Cl?
What type of kidney damage might you suspect?
Cl goes down as anion gap rises
HYPOCHLOREMIC WITH AN INCREASED ANION GAP
Glomerular Disease
