Urinary Tract Obstruction

Question 1

2 broad types of urinary tract obstruction?

Answer 1

Upper tract Lower tract

Question 2

3 types of upper tract obstruction? (i.e. supra-vesical)

Answer 2

PUJ Ureter VUJ (Physiological obstruction)

Question 3

5 types of lower tract obstruction? (i.e. bladder outflow obstruction)

Answer 3

Bladder Prostate Urethra Urethral meatus Foreskin (e.g. phimosis)

Question 4

What are the intrinsic causes of upper tract obstruction at the pelvi-ureteric junction (PUJ)?

Answer 4

• PUJ obstruction (physiological) - stone - ureteric tumour - blood clot - fungal ball (immunosuppressed patients)

Question 5

What are the intrinsic causes of upper tract obstruction at the ureter?

Answer 5

• stone - ureteric tumour (TCC) - scar tissue - blood clot - fungal ball

Question 6

What are the intrinsic causes of upper tract obstruction at the vesico-ureteric junction (VUJ)?

Answer 6

• stone - bladder tumour - ureteric tumour

Question 7

What are the extrinsic causes of urinary tract obstruction at the PUJ?

Answer 7

• PUJ obstruction (crossing vessel) - lymph nodes (tumour) - abdominal mass (tumour)

Question 8

What are the extrinsic causes of urinary tract obstruction at the ureter?

Answer 8

• lymph nodes (tumour, retroperitoneal fibrosis) - iatrogenic - abdominal/pelvic mass (tumour, pregnant uterus (physiological))

Question 9

What are the extrinsic causes of urinary tract obstruction at the VUJ?

Answer 9

• cervical tumour - prostate cancer

Question 10

3 symptoms of upper urinary tract obstruction?

Answer 10

Pain Frank haematuria Signs of complications (May have none until in renal failure)

Question 11

3 signs of upper urinary tract obstruction?

Answer 11

• palpable mass - microscopic haematuria - signs of complications

Question 12

2 important complications from upper urinary tract obstruction?

Answer 12

Infection and sepsis Renal failure !

Question 13

Is acute or chronic UTO more likely to be any painful?

Answer 13

Acute

Question 14

High v low pressure is a component of chronic UTO, what does high P mean for the function of the kidneys?

Answer 14

Can mess up the counter-current mechanism leading to renal failure

Question 15

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

Answer 15

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

Question 16

What investigations should be organised for Mr A?

Answer 16

USS (shows state of kidneys and bladder) CT (better in fatter people than USS; non-contrast (contrast can mess up kidneys)

Question 17

CT shown

Answer 17

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)

Question 18

What is the 4 step management of upper tract obstruction?

Answer 18

• 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

Question 19

What 2 things can be used for emergency treat ember of obstruction?

Answer 19

• Percutaneous nephrostomy insertion - Retrograde stent insertion

Question 20

What can be done for definitive treatment of obstruction - e.g. in stone, ureteric tumour, PUJ obstruction

Answer 20

Stone - uretoscopy and laser lithotripsy +/- basketing or ESWL Ureteric tumour - radical nephro-ureterectomy PUJ obstruction - laparoscopic pyeloplasty

Question 21

In Mr A, why would we not start with definitive treatment of obstruction?

Answer 21

If stone was lasered, the fragments broken off from it would carry bacteria from the infection into blood and cause sepsis

Question 22

How is nephrostomy done?

Answer 22

Percutaneous puncture Usually under LA/sedation US or x-ray guidance (Careful - bleeding/adjacent organs!)

Question 23

Describe a ureteric stent

Answer 23

Silicone Polyurethane Nickel titanium

Question 24

What clinical symptoms/conditions can lower tract obstruction present with?

Answer 24

LUTS (inc urinary incontinence) Acute or chronic urinary retention Recurrent UTI and sepsis Frank haematuria (possible infection) Formation of bladder stones Renal failure !

Question 25

What should be done immediately in retention?

Answer 25

CATHETERISATION (Urethral catheter 14/16F; record residual; 2 attempts (then introducer if GA experience); 16F SPC if urethra impassable

Question 26

65 yr old; acute retention; in agony; creatinine 70 65 yr old; chronic retention; pain free; creatinine 170 Who gets the bed?

Answer 26

CHRONIC retention patient

Question 27

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?

Answer 27

Urethral catheterisation Suprapubic catheterisation

Question 28

What can be done for definitive treatment of lower tract obstruction in the case of BPE, urethral stricture, meatal stenosis, phimosis

Answer 28

BPE - TURP Urethral structure - optical urethrotomy Meatal stenosis - meatal dilatation Phimosis - circumcision

Question 29

Features of high pressure chronic retention?

Answer 29

Painless Incontinent Raised CR Bilateral hydro-nephrosis

Question 30

Features of low pressure chronic retention?

Answer 30

Painless Dry Normal CR Normal kidneys (Not gna diurese significantly)

Question 31

2 major complications of UTO?

Answer 31

Decompression haematuria Post obstructive diuresis