Painful inability to void with a palpable distended bladder, usually from bladder outflow obstruction.
Investigations
- • Bladder scan and residual volume after catheterisation
- • U&E and creatinine to detect high-pressure retention
- • MSU, PSA (defer 6 weeks after catheterisation)
- • Renal ultrasound if creatinine raised
Management
- • Urethral catheterisation and record residual volume
- • Start tamsulosin 400 mcg and plan trial without catheter at 48–72 h
- • Treat constipation and stop anticholinergics/opioids
- • Suprapubic catheter if urethral access fails
Complications
- • Post-obstructive diuresis (>200 mL/h) needing fluid replacement
- • Haematuria ex vacuo
- • Acute on chronic renal failure
Clinical pearls
- • Residual >1 L suggests chronic high-pressure retention — do not discharge without renal function check
Related in WardRound
Educational — verify locally.
