10. Urinary Retention Flashcards
describe the differences between acute and chronic urinary retention presentation, management and consequences
Acute
1) painful
2) requires urgent catheterisation - or bladder can be permanently damaged
3) increased pressure can cause backup - hydronephrosis - and kidney failure (as starling forces in kidney are disrupted)
Chronic
1) painless
2) does not require catheterisation
3) incomplete voiding (urine seen on post-void residual scan) can cause urinary incontinence or UTIs
why can ageing cause urinary retention
detrusor muscle weakness
why can medications cause urinary retention
interfere with nerve signals to bladder and prostate
suggest neurological causes for urinary retention
- brain dysfunction (pontine storageand micturition centres)
- spinal cord dysfunction:
- sacral spinal cord damage/compression - detrusor areflexia
- suprasacral damage - detrusor-sphincter dysynergia (bladder contracts but sphincter doesn’t relax)
- spina bifida, etc. - peripheral nerves dysfunction (sensory afferents or motor efferents): eg diabetic cystopathy, MS, tabes dorsalis
name an important complication of urinary retention - how should this be treated
- infected obstructed system - UROSEPSIS - has high mortality if left untreated
- can develop into PYONEPHROSIS - standing column of septic urine in upper urinary tract, inc. kidney
- Ps need urgent stabilisation and decompression: NEPHROSTOMY - artificial opening between kidney and skin allowing for urinary diversion directly from renal pelvis
why is there a risk of diuresis and dehydration after catheterisation
high pressure in renal system can cause kidney dysfunction and loss of corticomedullary conc. gradient
name the 2 types of catheterisation - which is preferable long term?
- through urethra
- supra-pubically: preferable as long term option (e.g. in MS, neurologic Ps) as decreased risk of infection and allows sexual function
