Retention Flashcards
definition of acute retention
NEW onset inability to pass urine
causes of acute retention
BPH, UTI, constipation, epidural, medication like antimuscarinics, neurological causes like stroke
investigations for acute retention
post void bladder scan, bloods (FBC, CRP, U+E), catheterised sample of urine (CSU - to look for the presence of infection)
what do you do if you suspect a high pressure retention (where the antireflux mechanisms are overcome)
US to check for hydronephrosis
Management of acute retention
1) catheterise 2) treat any underlying cause 3) if over 1000ml drained, may be a chronic element and monitor for post obstructive diuresis (>200mls/hr for 6 hours) and low osmolarity urine 4) then TWOC
Complications of retention
AKI and increased chance of UTI and renal stones due to urinary stasis
why does post obstructive diuresis happen in chronic retention
the loop of henle is damaged and cannot reabsorb water using its concentration gradient as it normally does
definition of chronic retention
longstanding inability to pass urine which causes significant bladder distension and bladder desensitisation hence minimal discomfort
cause of chronic retention in females
pelvic organ prolapse
most common cause of chronic retention in men
BPH
why is overflow incontinence worse at night (nocturnal enuresis) in chronic retention
reduced sphincter tone at night
what is a high pressure retention
high intravesicular pressure which then overcomes the antireflux mechanism of the bladder
how is chronic retention managed
long term catheterisation / suprapubic catheter / intermittent self catheterisation (do not do TWOC especially if it is high pressure)
when is catheterisation contraindicated
if there is a chance of urethral injury (from trauma) in this case use a suprapubic catheter
storage / voiding symptoms
Frequency
Urgency
Nocturia
Weak stream
Intermittency
Strain
Emptying incomplete
(post micturition dribble)
