Urinary Tract Obstruction Flashcards
2 broad types of urinary tract obstruction?
Upper tract Lower tract
3 types of upper tract obstruction? (i.e. supra-vesical)
PUJ Ureter VUJ (Physiological obstruction)
5 types of lower tract obstruction? (i.e. bladder outflow obstruction)
Bladder Prostate Urethra Urethral meatus Foreskin (e.g. phimosis)
What are the intrinsic causes of upper tract obstruction at the pelvi-ureteric junction (PUJ)?
- PUJ obstruction (physiological) - stone - ureteric tumour - blood clot - fungal ball (immunosuppressed patients)
What are the intrinsic causes of upper tract obstruction at the ureter?
- stone - ureteric tumour (TCC) - scar tissue - blood clot - fungal ball
What are the intrinsic causes of upper tract obstruction at the vesico-ureteric junction (VUJ)?
- stone - bladder tumour - ureteric tumour
What are the extrinsic causes of urinary tract obstruction at the PUJ?
- PUJ obstruction (crossing vessel) - lymph nodes (tumour) - abdominal mass (tumour)
What are the extrinsic causes of urinary tract obstruction at the ureter?
- lymph nodes (tumour, retroperitoneal fibrosis) - iatrogenic - abdominal/pelvic mass (tumour, pregnant uterus (physiological))
What are the extrinsic causes of urinary tract obstruction at the VUJ?
- cervical tumour - prostate cancer
3 symptoms of upper urinary tract obstruction?
Pain Frank haematuria Signs of complications (May have none until in renal failure)
3 signs of upper urinary tract obstruction?
- palpable mass - microscopic haematuria - signs of complications
2 important complications from upper urinary tract obstruction?
Infection and sepsis Renal failure !
Is acute or chronic UTO more likely to be any painful?
Acute
High v low pressure is a component of chronic UTO, what does high P mean for the function of the kidneys?
Can mess up the counter-current mechanism leading to renal failure
Mr A is a 50yr old man who presents to A&E with L sided loin pain; the pain is colicky and causes nausea and vomiting; he has no significant PMH and is not on any meds
On examination, his temp is 40C, pulse is 100bpm, BP is 90/60mmHg, resp rate is 20bpm, O2 sat is 89% on air; he is extremely tender over left loin and flank areas
What investigations should be organised for Mr A?
USS (shows state of kidneys and bladder) CT (better in fatter people than USS; non-contrast (contrast can mess up kidneys)
CT shown
White blob - stone in upper tract Black circle in kidney - urine that is obstructed Shows ‘obstructed infected left urinary tract’ = PYONEPHROSIS (hydronephrosis - without infection; pynonephritis- less likely to die (pyonephrosis carries 20% mortality)
What is the 4 step management of upper tract obstruction?
- resuscitation (ABCs, IV access, bloods, urine & blood cultures, fluid balance monitoring; IV fluids, broad-spectrum abx if approp; analgesia; HDU care +/- renal RRT if approp) - investigations (including imaging) - emergency treatment of obstruction - definitive treatment of obstruction
What 2 things can be used for emergency treat ember of obstruction?
- Percutaneous nephrostomy insertion - Retrograde stent insertion
What can be done for definitive treatment of obstruction - e.g. in stone, ureteric tumour, PUJ obstruction
Stone - uretoscopy and laser lithotripsy +/- basketing or ESWL Ureteric tumour - radical nephro-ureterectomy PUJ obstruction - laparoscopic pyeloplasty
In Mr A, why would we not start with definitive treatment of obstruction?
If stone was lasered, the fragments broken off from it would carry bacteria from the infection into blood and cause sepsis
How is nephrostomy done?
Percutaneous puncture Usually under LA/sedation US or x-ray guidance (Careful - bleeding/adjacent organs!)
Describe a ureteric stent
Silicone Polyurethane Nickel titanium
What clinical symptoms/conditions can lower tract obstruction present with?
LUTS (inc urinary incontinence) Acute or chronic urinary retention Recurrent UTI and sepsis Frank haematuria (possible infection) Formation of bladder stones Renal failure !
What should be done immediately in retention?
CATHETERISATION (Urethral catheter 14/16F; record residual; 2 attempts (then introducer if GA experience); 16F SPC if urethra impassable
65 yr old; acute retention; in agony; creatinine 70 65 yr old; chronic retention; pain free; creatinine 170 Who gets the bed?
CHRONIC retention patient
4 same steps as upper tract obstruction management (resuscitation; investigations inc bladder scan, USS renal tract; emergency treatment of obstruction; definitive treatment of obstruction); what 2 things could be done for emergency treatment of obstruction?
Urethral catheterisation Suprapubic catheterisation
What can be done for definitive treatment of lower tract obstruction in the case of BPE, urethral stricture, meatal stenosis, phimosis
BPE - TURP Urethral structure - optical urethrotomy Meatal stenosis - meatal dilatation Phimosis - circumcision
Features of high pressure chronic retention?
Painless Incontinent Raised CR Bilateral hydro-nephrosis
Features of low pressure chronic retention?
Painless Dry Normal CR Normal kidneys (Not gna diurese significantly)
2 major complications of UTO?
Decompression haematuria Post obstructive diuresis
