S10) Obstruction Flashcards
How can haematuria be detected in a patient?
- Visible haematuria
- Microscopic (3, 5 or 10 RBC’s)
- Dipstick +ve
Provide a differential diagnosis for haematuria
- Cancer: renal cell carcinoma, bladder cancer, advanced prostate carcinoma
- Stones
- Infection
- Inflammation
- BPH (large)
What are the causes of haematuria?
- Vascular
- Inflammatory
- Trauma
- Autoimmune
- Medications
- Infection
- Neoplasia
- Congenital
Describe the history one must take for a patient presenting with haematuria
Full urological history:
- SQITARS
- Presenting complaint
- Past medical history
- Drug history (OTC, prescription, illicit)
- Social and family history
What examinations are undertaken for a patient presenting with haematuria?
- Cystoscopy (look into bladder)
- Urological examination (abdomen, genitalia, PR exam, neurology)
- CT urography
What investigations are requested for a patient presenting with haematuria?
- Urine microscopy, culture & sensitivity
- Urine cytology
How can one manage a patient presenting with haematuria other than treating the underlying cause?
- ABCDE + stabillise
- Bloods
- 3 way catheter and irrigation
- CT angiogram (if significant bleed)
What are the different types of urinary retention?
- Acute urinary retention (painful)
- Chronic urinary retention (not painful)
How can one differentiate between acute and chronic urinary retention?
History, examination, clinical picture:
- Acute – painful to void, impaired eGFR (urological emergency)
- Chronic – non-painful to void, oliguria, urine in residual scan
Identify 4 circumstances when one should catheterise a patient?
- Painful acute urinary retention
- Acute on chronic urinary retention (unable to pass urine)
- High pressure chronic urinary retention (Pves > 30cmH2O)
- To monitor fluid balance, sepsis, trauma
Outline the clinical approach for a patient with urinary retention
- History
- Examination
- Bloods
- Bladder scan
- Neurological documentation
What is the mechanism for urinary retention?
⇒ Bladder outlet obstruction, catheterise
⇒ Low bladder contractile power
⇒ Interrupted sensory or motor innervation of bladder (± sphincter)
What are the causes of urinary retention in men and women respectively?
- Men: BPH, prostate cancer, urethral stricture, prostatic infection
- Women: prolapses, masses, Fowlers syndrome, preggers (progesterone can relax fibres in renal pelvis and the ureters)
What are the causes of urinary retention in both men and women?
- Clots n stones
- Drugs (anticholinergics, sympathomimetics)
- Pain
- Spinal cord compression/injury
- UTI
- recent surgery
- urethral strictures
- pelvic masses
- constipation - bowel can press on ureter
Describe how one treats patients presenting with urinary retention
Urethral catheterisation:
⇒ Clean the area
⇒ Use gloves and instillagel
⇒ Gently insert into urethral meatus (women) / into straight penis (men)
⇒ Inflate catheter balloon (& replace foreskin if retracted)
What difficulties patients can pose towards catheterisation?
- Men: phimosis, meatal stenosis, stricture, prostate, bladder neck
- Women: masses, prolapses, pelvic cancer
What is a suprapubic catheter?
A suprapubic catheter is a catheter that is left in place and involves the insertion of the catheter into the bladder through a hole in the abdomen
When are suprapubic catheters used?
- Long term conditions e.g. multiple sclerosis
- Urethra is damaged/blocked
- Patients have difficulties using an intermittent catheter
Identify 5 locations where stones can form in the urinary tract
- Kidney
- Ureter
- Bladder
- Prostate
- Urethra (men – rare)
What is ureteric colic?
Ureteric colic is severe and acute pain in the loin area due to the obstruction of the ureter by calculi
can be due to blood clots or sloughed papilla
can lead to acute renal failure if bilateral
How does ureteric colic present?
- Pain
- Haematuria
- Infection
- Impaired renal function (obstruction)
Outline the clinical approach for a patient presenting with ureteric colic
- History
- Examination
- Urinalysis
- CT KUB (kidneys, ureter, bladder)
- Abdominal X-ray (if visible stone)
Symptoms and stone size guides treatment for uteric colic.
Regardless, outline the basic management
- Place a stent to bypass the stone
- Uteroscopy
- Lasertripsy
- Stone ablation - break stone into powder and wee out
What is pyonephrosis?
- Pyonephrosis is the infection of the kidney which leads to pus in the upper collecting system which can progress to obstruction
- It has a very high mortality if untreated
What happens when a patient presents with acute sepsis?
Patients with infected obstructed upper tract need urgent stabilisation and decompression
What are some emergency procedures used on patients with acute sepsis in the upper urinary tract?
- Nephrostomy - place a needle right into pelvic area of kidney and drain
- Stenting - guided wire up the ureter to help urine flow from kidney to bladder
how can an obstruction increase the risk of a UTI and what else does it increase risk of?
there will be stasis of urine so more easy for infection to breed
reflux and stone formation
what are some neurological reasons for urinary retention
- congenital abnormalities effecting spinal chord
- external pressure on the cord or lumber nerve roots
- trauma to spinal cord
management of acute urinary retention
- catheterise and record residual volume
- history to check for cancer
- examine
- urine dip
- U & E
- BPH - alpha blocker to helo reduce flare up
management of chronic urinary retention
- catheterise and record residual volume
- history, examine, urine dip, U & E
- high pressures: high U&E, hydronephrosis, repeat episodes can cause scarring and CKD
- Low pressure: normal renal function, no hydronephrosis
- plan for long term catheterisation (they wont ever be able to void on their own again)
post obstructive diuresis
- lose too much water
- AKI → kidney cannot reabsorb enough water and loses corticocapillary gradient and can risk to worsening AKI
- urine output should be measured 24 hours after catheterisation
- if high volumes lost then give IV fluids
how can obstruction cause hydronephrosis
- blocked ureter
- causes increased pressure in the renal pelvis
- unilateral - caused by an upper UTI
- bilateral - caused by lower UTI
what happens in hydronephrosis
- progressive atrophy of the kidney
- back pressure is transmitted to distal parts of the nephron
- GFR declines and if obstruction is bilateral then patient goes into renal failure
- fluid in pelvis
where are possible sites of infection that can lead to hydronephrosis
- pelviureteric junction
- ureter → hydroureter
- neck bladder
describe what is happening in these graphs
B: no urine is leaving
C: urine is leaving but its taking a long time
D: still takes a while for dye to leave
what is a functional test you can do to diagnose for upper UT obstruction
MAG3
