Nphro - UO Flashcards
4 common sites of mechanical obstruction in the GUT
ureteropelvic junction
ureterovesical junction
bladder neck
urethral meatus
obstruction above the level of the bladder
a. unilateral hydronephrosis
b. bilateral hydronephrosis
c. either
A
obstruction below the level of the bladder
a. unilateral hydronephrosis
b. bilateral hydronephrosis
c. either
B
Most common cause of bilateral hydronephrosis in boys
posterior urethral valves
The following can cause urinary obstruction EXCEPT
a. congenital narrowing of the ureteropelvic junction
b. carcinoma of the colon and cervix
c. BPH
d. abnormalities in the pontine and sacral centers of micturition
e. AOTA
f. NOTA
F
cauda equine syndrome
a. overflow incontinence
b. fecal incontinence
c. both
d. neither
C
urinary retention as a consequence of
a. alphaadrenergic agents
b. cholinergic agents
c. both
d. neither
A; anticholinergic not cholinergic agent cause urinary retention
Hydronephrosis in pregnancy is due to
progesterone
unilateral compression by the enlarged uterus
unilateral compression by the enlarged uterus causes hydronephrosis in pregnancy. this is more often in the
a. right side
b. left side
A
True about Urinary obstruction
a. flank pain occurs due to distention of the collecting system or renal capsule
b. degree of distension has greater effect than rate of distension
c. chronic obstruction is painful
d. azotemia rarely develops
A;
b. rate of distention greater influence
c. chronic - painless
d. azotemia develops when overall excretory function is impaired
hemodynamic effects of acute urinary obstruction RBF - GFR - medullary blood flow - vasodilator prostaglandins, NO -
RBF - increase
GFR - decrese
medullary blood flow - deccrease
vasodilator prostaglandins, NO - increase
hemodynamic effects of chronic urinary obstruction RBF - GFR - vasoconstrictor prostaglandins RAAS -
RBF - decrease
GFR - decrease decrease
vasoconstrictor prostaglandins - increase
RAAS - increse
What happens when obstruction is released? (in terms of hemodynamics)
slow increase in GFR
Tubule effects in acute urinary obstruction
ureteral tubule pressures -
reabsorption of sodium, urea, water -
ureteral tubule pressures - increase
reabsorption of sodium, urea, water - increase
Tubule effects in acute urinary obstruction
medullary osmolarity -
concentrating ability -
transport functions for sodium, potassium, hydrogen -
medullary osmolarity - decrease
concentrating ability - decrease
transport functions for sodium, potassium, hydrogen - decrease
Tubule effects upon release of obstruction
tubule pressure -
solute load per nephron -
tubule pressure - decrease
solute load per nephron - increase
clinical features of acute urinary obstruction
pain
azotemia
oliguria or anuria
Clinical features of chronic ureteral obstruction
azotemia hypertension AVP-insensitive polyuria Natriuresis hyperkalemic hyperchloremic acidosis
Clinical features after release of obstruction
postobstructive diuresis
potential for vol depletion electrolyte imbalance due to losses of Na K Phosphate Mg and water
True of partial obstruction acute setting
a. downregulation of transporters
b. polyuria and dehydration
c. hyperkalemia and dRTA
d. mimic pre renal azotemia and high BUN/Crea
D
everything else for chronic
pertinent findings in history for urinary obstruction
difficulty in voiding
pain
infection
change in urinary volume
Treatment for recurrent UTI with a poor functioning kidney
nephrectomy
medical tx of BPH
alphaadrenergic blockers
5 alpha reductase inhibitors
treatment of neurogenic bladder
frequent voiding
cholinergic drugs
true of post obstructive diuresis
a. massive polyuria after relief of bilateral obstruction
b. urine is usually hypotonic and contain traces of sodium, chloride, potassium, phosphate and magnesium
c. both
d. neither
A;
contain large amounts of sodium, chloride, potassium, phosphate, magnesium
true of postobstructive diruesis
a. replace fluids in amounts equal the amount of urinary losses
b. more aggressive fluid management in hypovolemia, hypotension and/or electrolyte abnormalities
c. no danger of hypernatremia
d. use 0.90 saline
B
a. less
b. with danger
d. 0.45 saline
