Where it is
Behind the pubic symphysis. In men it sits in front of the rectum, above the prostate; in women in front of the uterus and vagina.
What it does
Holds about 300–500 mL comfortably; the urge to void usually starts at 150–250 mL. The detrusor muscle contracts and the sphincters relax during urination.
Clinical relevance
- Urinary retention causes lower abdominal distension and discomfort; overflow incontinence may occur.
- Catheter-associated urinary tract infections are among the most common hospital infections.
Nursing focus
- Use a bladder scanner before catheterizing for suspected retention.
- Keep the drainage bag below the bladder and off the floor, and remove catheters as soon as they are no longer needed.