What Is Urinary Retention?
Urinary retention is defined as the inability to completely or partially empty the bladder. You may be unable to start urination, or if you are able to start, you are unable to fully empty your bladder. Urinary retention can be sudden (acute) or can build up slowly over a period of time (chronic). Acute urinary retention generally means you are unable to pass any urine even though your bladder is full. If you have chronic urinary retention you can usually pass some urine but cannot completely empty your bladder.
Urinary retention can be attributed to two causes — either obstruction or non-obstruction.
If there is an obstruction (for example, bladder or kidney stones), a blockage occurs and urine cannot flow unimpeded through your urinary tract. This is the basis for acute urinary retention and is potentially life threatening. You must seek immediate emergency treatment. Non-obstructive causes include a weakened bladder muscle and nerve problems that interfere with signals between your brain and the bladder. If the nerves aren’t working properly, your brain may not get the message that the bladder is full.
The symptoms of acute urinary retention may include the following and will require immediate medical attention:
- inability to urinate
- painful, urgent need to urinate
- pain or discomfort in the lower abdomen
- bloating of the lower abdomen
The symptoms of chronic urinary retention may include
- urinary frequency—urination eight or more times a day
- trouble beginning a urine stream
- a weak or an interrupted urine stream
- an urgent need to urinate with little success when trying to urinate
- feeling the need to urinate after finishing urination
- mild and constant discomfort in the lower abdomen and urinary tract
The doctor will ask about your signs and symptoms and how long you have had them. He or she will also ask about your medical history and your drug use. A physical exam of the lower abdomen (belly) may show the cause or give the doctor clues. For men, the doctor may also perform a rectal exam to check the size of the prostate, a walnut-sized gland located between the bladder and the penis. An enlarged prostate might press the urethra and cause urinary retention. Other additional testing includes:
- Urinalysis to check for infection or blood in urine.
- Ultrasound to see how much urine remains in the bladder after voiding.
- Cystoscopy, a test where a tiny camera is inserted through the urethra, allowing the doctor to see the inside of the urethra and bladder.
- CT scan, which looks for stones or other blockages of the urine flow.
- Urodynamic tests of urine flow.
- Electromyography (EMG), which measures how well the muscles and nerves work around the bladder and the urethra.
For the acute form, a catheter is placed into the urethra in order to drain the bladder. Treatment of the chronic form or the acute form that becomes chronic will depend on the underlying cause. For men with an enlarged prostate, certain drugs may be used to try and shrink it. These include alpha-blockers and 5-alpha reductase inhibitors (finasteride and dutasteride). Also, surgery to remove the prostate or reduce its size may be considered.