Bladder Outlet Obstruction

Bladder outlet obstruction (BOO) is a blockage in the neck at the very bottom of your bladder. The neck is where your bladder connects to your urethra, which carries urine (pee) out of your body. A urinary tract blockage stops or slows down the flow of pee.

BOO is most common in people over age 65 and males. Possible urinary blockages include scar tissue, bladder stones, an enlarged prostate gland or prostate cancer. Women with cystocele (prolapsed bladder) are more likely to have a bladder outlet obstruction than other women. Children and babies, including developing fetuses, can also get BOO.

Rarely, a developing fetus can get bladder outlet obstruction in utero. Other names for this are fetal bladder outlet obstruction or fetal lower urinary tract obstruction (LUTO). When a fetus’s pee is blocked, it increases the size of their bladder and can cause kidney issues and other problems.

Symptoms of bladder outlet obstruction

Bladder outlet obstruction can cause symptoms of urinary tract obstruction. The name for these is lower urinary tract symptoms (LUTS).

You may have a urinary blockage if you:

• Have trouble starting your urine stream
• Feel like you have a full bladder but can’t empty it completely
• Pass pee frequently during sleeping hours
• Have pain in your lower abdomen or side
• Have a pee flow that starts and stops or is very slow
• Use the bathroom often, but very little pee comes out
• Feel pain when passing pee
• Feel an urgent need to empty your bladder

What causes a bladder outlet obstruction?

An enlarged prostate gland (benign prostatic hyperplasia or BPH) is a common cause of bladder outlet obstruction.

But many different things can cause a bladder outlet obstruction, like:

• Scar tissue in your urethra (urethral stricture)
• Bladder stones (hardened minerals)
• Procedures for stress incontinence
• Noncancerous (harmless) lesions or cysts
• Urethral, vaginal, uterine, bladder, rectal, prostate or cervical cancer
• Bladder or uterus falling down into your vaginal area (pelvic organ prolapse)
• Severe constipation or impaction of stool

Risk factors

Risk factors for bladder obstruction include:

• Lower maximum flow rate of urine
• Longer urine flow time
• Less efficient bladder emptying
• Older age

Complications of this condition

It’s important to treat a urinary tract blockage as soon as possible to prevent complications. Without prompt diagnosis and treatment, you may have complications like:

• Urinary tract infections
• Loss of some kidney function
• Kidney damage
• Kidney stones
• Inability to empty your bladder completely

How doctors diagnose this condition

A healthcare provider will perform a physical exam to diagnose bladder outlet obstruction. They’ll also want to know about your medical history and what you’ve been experiencing. They’ll ask you questions like:

• Do you feel pain in your abdomen, or pain when you pee?
• When you go to pee, does it take a while to start?
• Do you ever pee in your sleep?
• When you’re done peeing, do you feel like your bladder is still full, or partially full?
• When you pee, does your urine stream start and stop (out of your control)?

Tests to diagnose bladder outlet obstruction may include:

• Blood tests to check for kidney damage
• Urinalysis to check for blood or infection
• Pelvic ultrasound of your kidneys and bladder to find where the pee blockage is occurring
• Cystoscopy to look for narrowing of your urethra
• Urodynamic testing to show how the muscles of your bladder and sphincters function
• Electromyography (EMG) to check your muscle and nerve function
• Post-void residual urine test to see how much pee you have in your bladder after you pee
• CT urogram (a series of X-rays)
• MRI (imaging that uses radio waves)
• Voiding cystourethrogram (VCUG, a type of X-ray)

How is bladder outlet obstruction treated?

The type of treatment you get depends on what’s causing the urinary blockage. For example, a healthcare provider will use different treatments for bladder stones than for prostate cancer. For some people, medications like alpha-blockers or finasteride improve bladder outlet obstruction. For others, physical therapy or a pessary (device to support a woman’s pelvic organs) may help with bladder obstruction.

Procedures or surgeries for bladder outlet obstruction may include:

• Foley catheter to drain pee from your bladder
• Surgical procedures to remove the obstruction
• Transurethral bladder neck incisions
• Sacrocolpopexy for pelvic organ prolapse
• Laser lithotripsy for stones
• Urethroplasty for strictures

Many of these urological surgeries are minimally invasive. That means you can expect a shorter hospital stay and a quicker recovery. Recovery time varies by procedure.

While waiting for treatment to fix bladder outlet obstruction, you may be able to unblock urine flow at home. You can learn to use a catheter to empty your bladder (self-catheterization). If you have a penis, you may get a better urine (pee) flow by sitting down to pee. Or you may be able to pass more pee by leaning forward for 30 seconds before trying to pee again.

When should I see my healthcare provider?

Go to the emergency department if the pain from a urinary tract blockage is unbearable. This could be a sign of complications. You should also seek immediate help if you can’t pass pee or have a urinary tract infection.

If you’ve had surgery, you’ll need follow-up appointments with your provider. After you’ve recovered, contact your provider if you have problems peeing again.

You may want to ask your healthcare provider:

• What’s the cause of bladder outlet obstruction in my case?
• Could it happen again?
• What’s the best treatment option for me?

What can I expect if I have this condition?

Unless the pain is unbearable, bladder outlet obstruction shouldn’t keep you from your normal daily activities.

It’s comforting to know that healthcare providers can treat most cases of bladder outlet obstruction. Your BOO-related symptoms should go away with treatment. But bladder outlet obstruction can come back. In some cases, you may need surgery.

The cause of a bladder outlet obstruction affects your prognosis (outlook). It’s different for each case.