Obstruction And Urolithiasis Flashcards
What is acute urinary retention?
Painful inability to void with a residual volume of 300-1500ml. Caused by BPH, urethral stricture, malignancy or tumours.
What is chronic urinary retention?
Painless obstruction of the urinary system. Patient may still be able to void. Residual volume between 300 and 4000ml. Caused by BPH, gradual occlusions and neurological conditions.
How is acute urinary retention managed?
Catheterisation, record urinary volume.
Examine abdomen and ruin dipstick/ UandE for causes.
How is chronic urinary retention managed?
Catheterise and record residual volume.
Examine and conduct urine dip and UandE.
Classify as high or low pressure.
Plan for long term catheterisation or intermittent self catheterisation.
What would classify high pressure chronic urinary retention?
What about low pressure?
Abnormal UandE, hydronephrosis (may lead to renal scarring and CKD).
Normal renal function.
What is post obstructive diuresis?
Following resolution of urinary retention, kidneys may over diurese leading to worsening AKI. As such monitor urine output for 24 hours after catheter removal and support with IV fluids.
What is hydronephrosis?
Dilation of the renal pelvis and calyces due to obstruction at any point of the urinary tract, resulting in increased pressure. Leads to AKI, commonly caused by BPH.
What commonly causes acute ureteric obstruction?
What type of pain does this result in?
Renal calculi, blood clots or sloughed papillae.
Results in renal colic (pain radiating from loin to groin. Can precipitate pyonephrosis.
What is pyonephrosis?
Infected obstructed kidney, often secondary to renal calculi. Failure to decompress results in sepsis, permanent renal function loss and sepsis.
How might urinary tract obstruction be diagnosed?
CT or USS showing obstruction.
Diuretic rengography - radioactive dye passed through kidney with furosemide and radioactivity measured. If decreasing slowly or plateaus - renal obstruction.
How can the upper urinary tract be drained?
Nephrostomy or JJ stent (inserted through urethra and ureter to hold blockage open).
What is urolithiasis?
Who are they most common in?
Renal calculi or stones.
Common in Caucasian males, especially if dehydrated.
Which 3 locations are most commonly occluded by urinary calculi?
Peviureteric junction,
Pelvic brim,
Vesicoureteric junction.
What types of calculi are there?
What differentiates them?
Calcium oxalate - most common - hypercalcaemia, hyperparathyroidism.
Calcium phosphate and calcium oxalate - alkaline urine.
Magnesium ammonium phosphate - urea splitting bacteria.
Uris acid - gout.
Cystine - inherited cystinuria.
How does urolithiasis present?
Renal colic due to increased peristalsis.
Strangury - urge to pass something that will not pass.
Recurrent UTI or haematuria,
Nausea and vomiting.
