A 20-year-old woman arrived at the emergency department by ambulance after a witnessed assault outside of a bar just after 2 a.m. She complained of abdominal pain and back pain, and her friends said she was hit once in the abdomen with a fist but had no other injuries.
The patient was intoxicated and had abdominal pain without focal tenderness or guarding. Initial labs revealed a negative pregnancy test, a hemoglobin of 15.1 g/dL, and a creatinine of 1.6 mg/dL.
Her abdominal pain worsened after about an hour in the ED and seemed out of proportion with the trauma. Given the elevated creatinine, a noncontrast CT of the abdomen and pelvis (shown) was ordered to evaluate for the source of the abdominal pain. What is the diagnosis?
Find the diagnosis and case discussion on next page.
Diagnosis: Intraperitoneal Bladder Rupture
The patient's CT returned with significant free fluid in the abdomen from an unclear source. A contrast-enhanced CT (Image 2) was then ordered to evaluate for a source of bleeding, but the CT was unremarkable except for free fluid. The team reviewed the CT, the mechanism of injury, and the patient's labs, and ordered a retrograde cystogram (Image 3) to evaluate for other sources of fluid. It revealed an intraperitoneal bladder rupture, and the patient was promptly taken to the OR for surgical repair.
Bladder rupture occurs in only 1.6 percent of blunt trauma, but 85 percent of bladder rupture cases result from blunt trauma with half occurring in motor vehicle crashes. (BJU Int. 2004;94:27; http://bit.ly/2NeGalx; UpToDate. http://bit.ly/2N9aoXm; Urology. 2017;102:234; J Trauma Acute Care Surg. 2017;82:1087.) Pelvic fractures cause injury through direct bony trauma to the bladder wall, and seat belts can apply direct compression to the dome of a full bladder, resulting in increased pressure and rupture. Pelvic fractures are a risk factor for bladder rupture, but that is seen in only three percent of pelvic fractures. (J Trauma. 2009;67:1033.)
Patients with bladder rupture present with hematuria, abdominal pain, decreased urine output, inability to void (due to persistent hematuria that can lead to clots), and increased BUN or creatinine. Our patient had an elevated creatinine, which initially diverted the team from ordering a contrast study. Elevated creatinine is not caused by kidney injury but the reabsorption of creatinine by the peritoneal lining into the bloodstream similar to what is seen in peritoneal dialysis patients. Another win for waiving creatinine and ordering a contrast study!
Hematuria in a trauma patient should raise suspicion of bladder rupture until proven otherwise. It is important to order the right study, however, to evaluate for the location and type of injury. If associated with a pelvic fracture or straddle injury, a retrograde urethrogram should be the first study to evaluate for a bladder neck injury. Otherwise, a retrograde cystogram is the study of choice. This case highlights the importance of the appropriate CT to diagnose bladder rupture, and shows the flaws of noncontrast studies and contrast CT of the abdomen and pelvis that are used as anterograde cystograms in trauma. Anterograde filling of the bladder is unacceptable to rule out bladder rupture by CT in trauma.
Retrograde urethrograms and retrograde cystograms will allow physicians to classify the injury into extraperitoneal and intraperitoneal bladder ruptures. Extraperitoneal can be simple or complex (with associated open fracture, rectal or vaginal involvement, bladder neck injury, persistent hematuria). Once the diagnosis and location of the injury have been determined, a catheter will be placed or maintained, and the next step is dependent on the type of rupture.
- Simple: Give the patient a catheter to use for two to three weeks.
- Complex: Send the patient to the OR unless a bladder neck injury is present. If it is, repair within the first week to avoid fistula formation.
- Send the patient to the OR.
In all cases of bladder rupture and repair, a repeat retrograde cystogram should be performed at two weeks to ensure proper healing before removing the catheter.
Our patient went to the OR for surgical repair, and was found to have a 5 cm laceration to the dome of her bladder. As she recovered in the hospital, her creatinine quickly returned to 0.5 mg/dL. She was discharged with a catheter, and her follow-up retrograde cystogram showed no evidence of a leak. Her catheter was removed, and her follow-ups have been without complication. Later in the patient's hospital course, she was able to tell the team that she had been drinking alcohol, and had not urinated for four hours. Alcohol ingestion not only increases urine production but also decreases the urge to urinate, leading to a bladder at risk for rupture spontaneously or by minor trauma to the abdomen.
Bladder rupture should be considered in trauma patients with hematuria, decreased urine output, elevated creatinine, or peritonitis. An elevated creatinine should not sway physicians away from ordering appropriate CT imaging. Anterograde cystograms are unacceptable to evaluate for a bladder injury. Management and disposition are based on whether the injury is extraperitoneal or intraperitoneal. Extraperitoneal ruptures (if simple) can go home with a catheter, while intraperitoneal ruptures need to go emergently to the operating room.
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Dr. Eutermoseris an assistant professor of emergency medicine at Denver Health and University of Colorado Hospital.Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.