Urology Flashcards
causes of urinary tract obstruction?
Luminal:
stones, blood clots, sloughed papilla
Mural:
congenital / acquired stricture, tumour: renal, ureteric, bladder
neuromuscular dysfunction
extramural:
prostatic enlargement,
abdo/ pelvis mass/ tumour
retroperitoneal fibrosis
presentation of acute upper urinary tract obstruction?
loin pain -> groin
presentation of acute lower urinary tract obstruction?
bladder outflow obstruction precedes severe suprapubic pain w distended palpable bladder
presentation of chronic upper urinary tract obstruction?
flank pain
renal failure (may be polyuric)
presentation of chronic lower urinary tract obstruction?
frequency, hesitancy, poor stream, terminal dribbling, overflow incontinence
distended palpable bladder +/- large prostate PR
ix of urinary tract obstruction?
bloods: FBC, U+E
urine: dip, MCS
imaging:
US: hydronephrosis or hydroureter
Anterograde/ retrograde ureterograms: allow therapeutic drainage
radionucleotide imaging: renal function
CT/ MRI
mx of Upper urinary tract obstruction?
nephrostomy
ureteric stent

mx of lower urinary tract obstruction?
urethral or suprapubic catheter
complications of ureteric stents?

common:
infection, haematuria, trigonal irritation, encrustation
rare:
obstruction, ureteric rupture, stent migration
causes of urethral stricture?

trauma e.g. pelvic #, instrumentation
Infection e.g. gonorrhoea
Chemotx
balantitis xerotica obliterans (male lichen sclerosus)
presentation of urethral stricture?
hesitancy
poor stream
terminal dribbling
strangury: painful, frequent urination of small volumes that are expelled slowly only by straining and despite a severe sense of urgency, usually with the residual feeling of incomplete emptying.
pis-en-deux: residual urine results in a desire to pass urine soon after voiding
examination of urethral stricture?
PR: exclude prostatic cause
Palpate urethra through penis
examine meatus
ix of urethral stricture?
urodynamics:
decreased peak flow rate
increased micturation time
urethroscopy and cystoscopy
retrograde urethrogram

mx of urethral stricture?
internal urethrotomy
dilatation
stent

complications of obstructive uropathy?
Hyperkalaemia
metabolic acidosis
post-obstructive diuresis
Na and HCO3 losing nephropathy
infection
what is post obstructive diuresis?
Kidneys produce a lot of urine in the acute phase after relief of obstruction.
must keep up w losses to avoid dehydration
what is Na and HCO3 losing nephropathy following obstructive uropathy?
diuresis may -> loss of Na and HCO3
may require replacement with 1.26% NaHCO3
causes of urinary retention?
mechanical obstruction:
BPH
urethral stricture
clots, stones
constipation
dynamic obstruction: increased smooth muscle tone
post operative pain
drugs
neurological:
sensory/ motor innervation affected
pelvic surgery
MS
DM
spinal injury/ compression
myogenic:
overdistension of the bladder
Post-anaesthesia
High alcohol intake
features of acute urinary retention
suprapubic tenderness
palpable bladder: dull to percussion, cant get beneath it
large prostate on PR: check anal tone and sacral sensation
<1 L drained on catheterisation
imaging of acute urinary retention?
US: bladder volume, hydronephrosis
pelvic XR
mx of acute urinary retention?
analgesia
catheterise:
use correct catheter, e.g. 3 way if clots
+/- STAT gentamicin cover
hourly UO + replace: post obstruction diuresis
Tamsulosin: decreases risk of recatherisation after retention
TWOC after 24-72ha
presentation of chronic urinary retention?
insidious as bladder capacity increases (> 1.5L)
typically painless
overflow incontinence/ nocturnal enuresis
acute on chronic retention
lower abdo mass
UTI
renal failure
high vs low pressure chronic urinary retention?
high pressure:
high detrusor pressure @ end of micturition
typically bladder outflow obstruction ->
bilateral hydronephrosis and decreased renal function
Low pressure:
low detrusor pressure @ end of micturition
large volume retention w very compliant bladder
kidney able to excrete urine
no hydronephrosis -> normal renal function
mx of high pressure chronic urinary retention?
catheterise if
- renal impairment
- pain
- infection
Hourly UO + replace: post obstruction diuresis
consider TURP before TWOC







