Extraperitoneal Bladder Rupture

Extraperitoneal bladder rupture is a tear of the bladder wall outside the peritoneal covering, at the base, anterior wall or lateral wall. Urine collects in the retropubic space and can track into the abdominal wall, thigh, scrotum and perineum if pelvic fascia is breached.

It accounts for about 55 to 65% of bladder ruptures and is most often caused by pelvic fracture (80 to 90%), through laceration by a bone spicule or shearing of the fixed bladder base.

Other causes are penetrating injury and iatrogenic injury (endoscopic resection of bladder tumour or prostate, pelvic or hernia surgery, midurethral sling trocar passage, catheterisation).

Pathophysiology. Urine extravasates into the perivesical space with little absorption, so metabolic derangement is uncommon. Perivesical haematoma and urinoma become infected if not drained, causing pelvic abscess, osteitis pubis and fistula.

Complicated rupture involves the bladder neck, rectum or vagina, or bone fragments within the bladder.

Gross haematuria in almost all, suprapubic pain and tenderness, inability to void or small volumes, lower abdominal bruising, and perineal, scrotal or thigh swelling with extravasation. Signs of pelvic fracture are usually present. Later features are fever, pelvic abscess and persistent leak.

• CT cystography or plain cystography with 300 to 350 mL of dilute contrast in adults, with post-drain images, since a small leak may appear only after drainage. Extraperitoneal leak shows as flame shaped streaks of contrast in perivesical fat.
• Urethrography first when there is blood at the meatus.
• Cystoscopy before surgery to inspect the bladder neck, orifices and any bone fragments.
• Haemoglobin, creatinine, urine culture, CT for associated injury.

Differential diagnosis.

• Intraperitoneal or combined rupture
• Urethral injury
• Ureteric injury
• Pelvic haematoma
• Bladder contusion
• Renal injury

• Uncomplicated rupture: catheter drainage alone with a 16 to 22 Fr urethral balloon catheter for 10 to 14 days, up to 3 weeks, with cystography before removal. Most heal within 2 weeks and almost all within 4 weeks. Operate if the leak persists at 3 to 4 weeks. A suprapubic catheter is the alternative when urethral injury is suspected.
• Surgical repair indications: bladder neck involvement, bone fragments in the bladder wall or lumen, entrapped bladder wall, rectal or vaginal injury, open pelvic fracture, planned anterior internal fixation of the pelvis (to lower hardware infection risk), failed conservative treatment and persistent clot causing bleeding.
• Technique: two layer closure with absorbable suture from inside or outside, drain the perivesical space, catheter for 10 to 14 days, and cystography before removal.
• Clot retention: irrigate through a 20 to 24 Fr three way catheter.
• Antibiotics: ceftriaxone 2 g intravenously once daily for open fracture or infected urinoma, with metronidazole 500 mg intravenously every 8 hours when there is rectal injury, stopped once wounds are closed and contamination is excluded, usually within 24 to 72 hours. Routine prophylaxis during catheter drainage is not needed, and symptomatic infection is treated by culture.

Monitoring. Cystogram at 10 to 14 days and removal only when there is no leak. Review at 6 weeks for voiding and continence. After pelvic fracture, watch for urethral stricture.

Referral and escalation. Refer to urology. Urgent referral for combined rupture, bladder neck injury, rectal injury, pelvic sepsis or failure to heal.