Urinary Tract Obstruction Treatment & Management

Consultation with a urologist should be obtained in patients with urinary tract obstruction, as in hydronephrosis or urinary retention. A patient with complete urinary tract obstruction; any type of obstruction in a solitary kidney; obstruction with fever or infection; or renal failure needs immediate attention by a urologist. Patients with pain that is uncontrolled with oral medications or with persistent nausea and vomiting that causes dehydration also need immediate urological attention.

A partial urinary tract obstruction in the absence of infection can be initially managed with analgesics and prophylactic antibiotics until a complete urologic evaluation is performed and definitive management is completed.

Antibiotics are often given for prophylaxis and should cover common urinary tract pathogens. Commonly used antibiotics include trimethoprim-sulfamethoxazole, nitrofurantoin, cephalosporins, and fluoroquinolones.

Pain secondary to urinary tract obstruction is often managed with oxycodone, hydrocodone, acetaminophen, and nonsteroidal anti-inflammatory medications.

The goal of surgical intervention is to completely relieve the urinary tract obstruction. This can be evaluated with reimaging to ensure that the obstruction is resolved, as well as renal function monitoring with a creatinine laboratory test. The recovery of renal function depends on the severity and duration of the obstruction.

Different interventions can be performed to temporarily relieve the point of obstruction. Surgical intervention is usually obtained once the point of obstruction is identified with radiographic imaging.

Lower urinary tract obstruction (bladder, urethra) can be relieved with the following:

• Urethral catheter

  • A urethral catheter (size 8F-24F) is a flexible external catheter that extends from the bladder through the urethra.
  • A physician or nurse can place it. If catheter placement is difficult, a urologist may be needed to avoid urethral trauma. The urologist may need to perform urethral dilation, cystoscopy, or both to pass the catheter.
  • The catheter can be left indwelling, or, as an alternative, the patient can perform clean intermittent catheterization.
  • If blood is present at the urethral meatus after pelvic trauma and suspicion of urethral injury exists, a urologist should be consulted prior to catheter placement. Retrograde urethrography needs to be performed to rule out urethral injury.
• Suprapubic tube or catheter: If a Foley catheter cannot be passed, a suprapubic tube can be placed percutaneously (at the bedside) or in an open fashion (in the operating room). A suprapubic tube is placed on the lower anterior abdominal wall, approximately 2 finger-breadths above the pubic symphysis. Ultrasound guidance should be used for bedside procedures to ensure proper placement without injury to adjacent structures. In patients with previous abdominal surgery, adhesions and scar tissue may have changed the normal bowel location, so an open approach may be preferred.

Upper urinary tract obstruction (ureter, kidney) can be relieved with the following:

• Ureteral stent: A ureteral stent is a flexible tube that extends from the renal pelvis to the bladder. It can be placed during cystoscopy to relieve obstruction along any point in the ureter. A ureteral stent generally needs to be changed every 3 months.
• Nephrostomy tube: A nephrostomy tube is a flexible tube that is placed through the back directly into the renal pelvis. If a ureteral stent cannot be placed cystoscopically in a retrograde fashion, a percutaneous nephrostomy tube can be inserted for relief of hydronephrosis. If needed, a ureteral stent can then be passed in an antegrade fashion through the nephrostomy tube tract.

The following are urologic emergencies that require immediate attention and intervention:

• Complete urinary tract obstruction
• Any type of obstruction in a solitary kidney
• Obstruction with fever, infection, or both
• Renal failure
• Pain that is uncontrolled with oral medications
• Nausea and vomiting that causes dehydration

Before any surgical intervention or any manipulation of the urinary tract, broad-spectrum antibiotics should be initiated to prevent infection or urosepsis. Ideally, before any manipulation is performed, the urine should be sterile. However, this may not be possible in cases of emergent surgical intervention. Urine culture along with the administration of broad-spectrum antibiotics is important.

If cystoscopy and stent are needed emergently, coagulation is not a concern. If percutaneous drainage is necessary, coagulopathies should be corrected.

Different interventions can be performed to temporarily relieve the point of obstruction. If the planned procedure cannot be performed safely or is not adequate in relieving urinary tract obstruction, other modes of urinary tract decompression can be tried.

When a patient has long-standing urinary tract obstruction that has been relieved, they may experience postobstructive diuresis.^[4] This physiologic diuresis is usually self-limiting and can be managed conservatively with fluid replacement and, if needed, electrolyte replacement. Postobstructive diuresis is defined as diuresis of more than 200 mL/h for at least 2 hours. Patients with severe diuresis should receive intravenous fluid replacement in the form of half normal saline at 80% of the hourly urine volume for the first 24 hours, then 50%. Postobstructive diuresis usually lasts 24-72 hours. Most cases are not severe enough to require this level of attention.

Definitive treatment at the point of obstruction is needed after the acute obstruction is resolved. Adults and children often have different etiologies of urinary tract obstruction. Thus, various definitive surgical treatment options are available for each condition. After definitive treatment is achieved, a final imaging study is obtained to verify complete relief of the obstruction. The type of study performed, as well as the timing of the study, is left to the discretion of the urologist.

For excellent patient education resources, visit eMedicine's Kidneys and Urinary System Center. Also, see eMedicine's patient education articles Intravenous Pyelogram, Cystoscopy, Magnetic Resonance Imaging (MRI), and CT Scan.

A patient with urinary tract obstruction should see a urologist promptly because of the serious complications that the obstruction can impose. The following are complications of obstructive uropathy:

• Infection, including cystitis (bladder infection), pyelonephritis (kidney infection), abscess formation, and urosepsis
• Urinary extravasation with urinoma formation
• Urinary fistula formation
• Renal insufficiency or failure
• Bladder dysfunction secondary to a defunctionalized bladder
• Pain

The prognosis of urinary tract obstruction depends on the cause, location, degree, and duration of obstruction, as well as the presence of a urinary tract infection. The longer the duration of obstruction, the greater the severity of obstruction, and the presence of a concomitant infection can lead to a worse prognosis. The prognosis is favorable if the renal function is normal, the infection is cleared, and the obstruction is relieved in a timely manner.

As time goes on, new procedures emerge and old procedures are modified to relieve urinary tract obstruction. In addition, with newer cameras and equipment and the use of laparoscopy, surgical intervention is becoming more advanced.