444 CHAPTER 10 Trauma to the urinary tract

Bladder injuries

Other situations in which the bladder may be injured

These include TURBT, cystoscopic bladder biopsy, TURP, cystolithopaxy, penetrating trauma to the lower abdomen or back, cesarean section (especially as an emergency), minor trauma in the inebriated patient, rapid deceleration injury (e.g., seat belt injury with full bladder in the absence of a pelvic fracture), and spontaneous rupture after bladder augmentation.

Types of perforation

•Intraperitoneal perforation—the peritoneum overlying the bladder is breached allowing urine to escape into the peritoneal cavity.

•Extraperitoneal perforation—the peritoneum is intact and urine escapes into the space around the bladder, but not into the peritoneal cavity (Fig. 10.11).

Making the diagnosis

During endoscopic urological operations (e.g., TURBT, cystolithopaxy), the diagnosis is usually obvious on visual inspection alone—a dark hole is seen in the bladder and loops of bowel may be seen on the other side. No further diagnostic tests are required.

In cases of trauma, the classic triad of symptoms and signs suggesting a bladder rupture is

•Gross hematuria

•Suprapubic pain and tenderness

•Difficulty or inability in passing urine

Additional signs are as follows:

•Abdominal distension

•Absent bowel sounds (indicating an ileus from urine in the peritoneal cavity)

•Free fluid on abdominal CT or ultrasound

These symptoms and signs are an indication for a retrograde cystogram.

Imaging studies

Either retrograde plain-film cystography or CT cystography are appropriate, depending on the patient’s clinical status and associated injuries. CT cystography is usually more appropriate, since many trauma patients are already undergoing CT for other abdominal, chest, head, or pelvic injuries.

Plain-film cystography is usually reserved for stable patients in the trauma bay or intraoperatively in patients taken directly for surgery.

Ensure the bladder is adequately distended with dilute contrast. With inadequate distension a clot, omentum, or small bowel may plug the perforation, which may not therefore be diagnosed. Use at least 300 mL of dilute (25%) contrast in an adult and (age + 2) x30 mL in children.

Clamping a urethral catheter and imaging the pelvis after IV contrast administration alone is usually nondiagnostic—repeat imaging with a distended bladder is required. For CT cystography, only a “full-bladder”

446 CHAPTER 10 Trauma to the urinary tract

phase is required—a post-drainage view is not required since the retrovesical space is well visualized.

For plain-film imaging, obtain three views: a scout film, an anteroposterior (AP) full-bladder film, and a post-drainage film, after the contrast has been completely drained from the bladder. Contrast drainage from a posterior perforation may be obscured by a bladder distended with contrast in the AP view.

In extraperitoneal perforations, extravasation of contrast is limited to the immediate area surrounding the bladder—a dense “flame-shaped” collection of contrast. Contrast may be noted extending into the retroperitoneum or scrotum, neither of which alters management.

In intraperitoneal perforations, loops of bowel or the peritoneal cavity may be outlined by the contrast.

Treatment

For treatment of bladder rupture, see Box. 10.5.

BLADDER INJURIES 447

Box 10.5 Treatment of bladder rupture

Extraperitoneal

When conditions are ideal, use bladder drainage with a urethral catheter for ~2 weeks followed by a cystogram to confirm the perforation has healed. If extravasation is noted, replace the catheter for 2 more weeks and repeat imaging; some injuries may take up to 6 weeks to heal.

Indications for surgical repair of extraperitoneal bladder perforation:

•Associated rectal or vaginal perforation

•When the patient is undergoing open fixation of a pelvic fracture, the bladder should be simultaneously repaired to prevent infection of the orthopedic hardware.

•If the bladder was opened to place a suprapubic catheter for a urethral injury

•Bone spike protruding into the bladder on CT

•Injuries discovered intraoperatively during nonurological surgery

•Injuries occurring as a result of penetrating trauma

•Poor urinary drainage due to clot obstruction

Intraperitoneal

When resulting from external trauma, surgical repair is required to prevent complications from leakage of urine into the peritoneal cavity. Selected patients with small iatrogenic perforations occurring during urological procedures (e.g., TURBT) may be treated nonoperatively under close observation with large-bore urethral catheter drainage and antibiotics alone.

Spontaneous rupture after bladder augmentation

Spontaneous bladder rupture occasionally occurs months or years after bladder augmentation and usually with no history of trauma. If the patient has spina bifida or a spinal cord injury, they usually have limited awareness of bladder fullness and pelvic pain. Their abdominal pain may therefore be mild and vague in onset and nature. Fever or other signs of sepsis may be present.

Have a high index of suspicion in patients with augmentation who present with nonspecific signs of illness. A cystogram usually, though not always, confirms the diagnosis. If doubt exists, consider exploratory laparotomy.