Introduction
Background
Bladder trauma is a semi-emergent condition, especially trauma that results in uroperitoneum. In such injuries, sepsis can develop within 24 hours if surgery with repair is not performed.
Radiologic examination is of paramount importance and should be performed to identify and classify the injury and to plan surgical repair, but it should not hinder patient treatment and stabilization. Several radiologic evaluations are appropriate, ranging from computed tomography (CT) cystography to basic retrograde cystography. All have been moderately well studied and require different equipment, locations, protocols, and operator expertise. It is always necessary to consider the stability of the patient's condition with regard to airway patency and circulation during the transfer and radiologic evaluation of the patient.
Trauma continues to be a major cause of morbidity and mortality in all areas of the world. Many immediately life-threatening insults are to the vital organs or to their blood supplies, and many diagnostic skills and studies are meant to rapidly reveal these complications. However, other life-threatening conditions must be addressed in a timely manner to avoid morbidity and, occasionally, mortality.Ideally, these conditions are diagnosed simultaneously, rather than individually, and the search for a universally applicable study is under way. Immediate surgery or another approach is commonly the diagnostic and therapeutic procedure of choice if the patient is exsanguinating or if his or her condition is deemed otherwise unstable.
For excellent patient education resources, visit eMedicine's Kidneys and Urinary System Center. Also, see eMedicine's patient education article Blood in the Urine.
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Pathophysiology
Mechanism of injury
Bladder trauma can occur in a number of settings. They are usually considered in the context of whether blunt or penetrating trauma is the inciting event. Blunt trauma is responsible for a large number of severe associated injuries, such as pelvic, splenic, renal, aortic, bowel, and hepatic insults. Injury is not necessarily localized to obviously traumatized areas.
Penetrating injury is often secondary to missiles, impaling objects, or knives. These injuries are of varying severity and often, but not always, result in damage to more focal areas. Some missile injuries have a vaguely estimable trajectory when one considers the entrance and exit wounds, and in the case of knife wounds, the impaling blade is often still in place at the time of presentation.
Classification of injury
Any discussion of bladder trauma must include the classification of injuries and associated injury patterns. In bladder trauma, the following 5 grades of insults are recognized:- Type I injuries - These are partial tears of the mucosa. The most common injury pattern of multisystem trauma patients, it is associated with blunt trauma for obvious reasons. Patients with type I injuries present with hematuria and suprapubic pain.1 However, no rupture is present, and findings on cystograms, conventional CT scans, and CT cystograms are normal, unless an intraluminal hematoma is present. This pattern is mentioned here only to point out that it is not a major bladder injury.
- Type II injuries - These are intraperitoneal bladder ruptures, and they account for approximately 10-20% of all major bladder injuries. Most commonly, they result from a direct blow to the distended organ. The bladder is weakest at its dome, where reinforcing tissue is absent; thus, intraperitoneal rupture usually occurs as a result of a rift in the bladder dome. Intraperitoneal fluid is observed bathing loops of bowel and presents in the paracolic gutters and mesenteric folds.
- Type III injuries - These are interstitial pattern injuries; they are described as intramural or partial-thickness lacerations of the intact serosa. Only CT cystography is commonly diagnostic and demonstrates intramural contrast within the bladder wall.2 This condition is most often secondary to blunt trauma. However, laceration by pelvic fragments or by a penetrating object, with minimal serosal damage, can present with a primarily interstitial pattern, with minimal extracystic urine demonstrated.
- Type IV injuries - These are extraperitoneal bladder injuries, and they are the most common bladder ruptures. In blunt trauma, a theoretical cause for laceration of the lower bladder is from secondary injury from pelvic fragments. Simple extraperitoneal ruptures involve urine buildup in the perivesicular space. More complex patterns of urine tracking involve different fascial planes. Urine or contrast material can be seen in the thigh or scrotum, with disruption of the inferior fascia of the urogenital diaphragm (perineal membrane). Urine may also breach the Scarpa or Camper fascia, and it may be observed in the rectus sheath or even under the skin.
- Type V injuries - These are combined ruptures resulting from a combination of penetrating and blunt trauma; they result in the presence of intraperitoneal and extraperitoneal urine. Type V injuries constitute 5-12% of bladder ruptures.
Frequency
United States
Trauma to the genitourinary system occurs in approximately 5-10% of all patients with trauma. Most of these injuries are secondary to blunt trauma, and approximately 10% of genitourinary calamities result in bladder trauma. Although limited accurate data are available, similar numbers apply to adults and in children. Bladder trauma is considered to be the second most common genitourinary injury after renal trauma.
International
Accurate data are limited.
Mortality/Morbidity
Morbidity and mortality are most commonly infectious in nature. Therefore, complications are usually associated with bladder rupture. Bladder disruption occurs in 5-10% of patients with pelvic fractures, and the type of perforation, with respect to classification, is important to prognosis. Broadly classified, approximately 50-85% of ruptures (many of which have associated pelvic fractures) are extraperitoneal, 15-45% of them are intraperitoneal, and only 1-10% of disruptions consist of both types.
In the event of an intraperitoneal rupture, a preexisting urinary tract infection, if present, will greatly influence morbidity and mortality. Thus, under certain circumstances, sepsis can ensue within 24 hours. Treated properly with operative repair and urologic consultation, nearly all patients with an intraperitoneal bladder rupture have few or no long-term complications.
Race
To the author's knowledge, no studies have been performed to determine whether racial differences exist in the frequency of bladder trauma.
Sex
No significant difference has been appreciated between the sexes with regard to the percentage of patients with concomitant bladder injury in the event of abdominopelvic trauma.
Age
Bladder trauma does not appear to be age specific.
- Limited data suggest that children have injury to their bladder in approximately 10% of the instances where genitourinary injury occurs.
- However, research suggests that preadolescent bladders are more intra-abdominal and that they consequently have a higher incidence of intraperitoneal rupture when this complication is present.
- Children are at risk of injury to the bowel, bladder, and lumbar spine, with rates of 20%, 4%, and 21%, respectively. Lap-belt ecchymosis is an indication for careful evaluation.
Anatomy
The bladder is located within the bony pelvis. (In adults it is considered to be a mostly extraperitoneal organ). There, the bladder, prostate, and proximal urethra are protected by 1 of the most secure bony enclosures in the body.
The bladder has a tetrahedral form when empty and has 4 primary surfaces. A superior, a posterior, and 2 inferolateral surfaces define the shape. The superior portion is triangular and is lined completely by the visceral peritoneum. This portion extends into the abdomen when distended and has little support from other structures. It is considered to be a dome when distended; in the female, it contacts the uterus, and in the male, it contacts the sigmoid colon in addition to loops of bowel.
The posterior surface, or fundus, of the bladder is anterior to the rectum, but it remains mostly retroperitoneal. A male bladder has the seminal vesicles coursing between the posterior bladder wall and the rectum. The posterior base of the bladder is supported by the rectum and is secured by the rectovesicular ligaments. In females, the posterior surface and the superior surface are loosely fixed to the upper vaginal wall and the uterus.
The pelvic floor musculature and overlying, loose areolar tissue support the inferolateral margins of the bladder. The pubovesical, medial, and paired lateral umbilical ligaments strengthen the bladder's association with the anterior body wall. The space of Retzius exists anterior to the bladder. This area consists of loose connective tissue that allows easy mobilization of the bladder from other surrounding structures. There is little preventing motion of the bladder, in that the only rigidly fixed point is the bladder neck. This is the primary adaptation to allow distention during filling.
Presentation
Trauma to the bladder is associated with significant trauma to the pelvis and intra-abdominal organs. Thus, patients present in a wide variety of ways, with large differences in the stability of their condition. Commonly, patients have few symptoms secondary to their bladder injury or even to rupture. The literature suggests that these patients have no strong propensity to develop peritonitis initially, even with a large amount of uroperitoneum.
Physical examination findings that are suggestive of bladder trauma include vague peritoneal signs or abdominal tenderness. However, more suggestive findings include isolated suprapubic tenderness, pelvic instability, or lap-belt ecchymosis. One study revealed that approximately 4% of children with lap-belt ecchymosis had suffered bladder rupture.3
Unlike upper renal trauma, bladder injury is essentially ruled out when no red blood cells (RBCs) are observed in the urine. Urogenital injury is suggested when microscopic hematuria is present (defined as >25,000-35,000 RBCs per high-power field). Gross hematuria is highly suggestive and certainly warrants full investigation. Gross hematuria is present in 95% of patients, and the remaining patients have microscopic hematuria.1
A problem can arise when bladder trauma is presumed to be the cause of hematuria, because this finding is not specific and can stem from more ominous sources, such as renal fracture. Urine should be collected from the first few hundred milliliters of the initial sample to prevent errors in interpretation. Furthermore, urethral trauma should always be ruled out before a Foley catheter is placed, especially when gross hematuria is present. Suggestive findings include blood at the meatus, a high-riding prostate, the patient's inability to void, perineal hematoma or scrotal swelling, and pelvic fracture.
Bladder injury is strongly associated with pelvic fracture. Eighty percent of bladder ruptures that are associated with pelvic fracture are extraperitoneal. Pelvic fracture is associated with bladder injury in 80% of patients, but the reverse is not true. Indeed, only 10% of pelvic fractures are associated with a major bladder trauma. When a pubic rami fracture exists or pubic symphysis diastasis is present, a higher index of suspicion should be maintained. A great deal of effort has been made to determine which pelvic fractures are associated with bladder injury. Patients with disruption of the pubic symphysis or pubic rami or with a vertically unstable pelvic fracture have a high incidence of concomitant bladder trauma, whereas those with an isolated acetabulum, femur, or iliac crest fracture have a low incidence of bladder injury or rupture.
Preferred Examination
The extent and type of radiologic evaluation required depends on the patient's condition and on the size of the area that may be affected. Many patients in stable condition require extensive screening, which means that diagnostic procedures should ideally provide views of large areas following quick and common preparation. For many patients in unstable condition or in patients with penetrating abdominal injuries who are immediately treated in the operating room (at the discretion of the surgeon), intraoperative radiologic evaluation is needed.2,4,5,6
Retrograde cystography, performed after urethrography, was considered the criterion standard for evaluation of bladder trauma. However, support has grown for using computed tomography (CT) cystography in proper diagnosis. Initial studies were not indicative of the reliability of CT scanning when retrograde contrast enhancement was not used. However, contemporary studies have overwhelmingly demonstrated that the technique is sensitive and accurate, provided that adequate bladder distention (with at least 350-400 mL of contrast material) is achieved before the study is performed. In diagnosing bladder rupture, CT cystography, performed with 400 mL of contrast material that is administered in a retrograde fashion, is as accurate as plain radiography with retrograde cystography.2
Ultrasonography is not sensitive or specific enough to be useful for evaluation of bladder rupture.
Retrograde cystograms have long been used for detecting bladder rupture. They are nearly 100% sensitive for detecting rupture, provided that adequate distention is accomplished and that postvoiding images are obtained. However, they are time consuming, the examinations are costly when one considers their value relative to their benefit, and they require extra radiography that does not occur in addition to necessary trauma evaluation. Furthermore, they are not useful in thoroughly evaluating other structures present in the abdomen and pelvis.
CT retrograde cystograms are completed in the radiology suite when routine spiral scans of the head, neck, chest, and abdomen and pelvis are performed. CT retrograde cystography generally requires the same retrograde introduction of contrast agent as does retrograde cystography. However, unlike plain radiography, the technique does not require multiple images, including postvoiding and oblique views. Thus, this procedure is less time consuming and, some would argue, less costly. At 1 hospital cited in the literature, the cost of CT cystography was $500 or more, a marginal increase over a plain radiographic examination. Costs should be specifically evaluated at each institution.
A final step is the washout study. After the full-bladder findings are recorded (on radiographs or CT scans), the bladder is drained. If no residual contrast enhancement is present, the examination is completed, and the results are negative. If residual contrast enhancement is present in the bladder area, fluid (eg, sterile water) is used to lavage the bladder. If no residual contrast enhancement is noted after drainage, the examination is completed, and the results are negative. If contrast enhancement remains, a bladder wall injury is present.
CT cystography may be used somewhat less often in patients who are not undergoing CT scanning for another reason. In a study of 157 patients with hematuria, an absence of free fluid on abdominopelvic CT scans was a strong negative predictor of bladder rupture.7 In such patients, not performing cystography may be reasonable.
Further study into this matter is warranted. Perhaps 1 of the greatest advantages of retrograde CT cystography with prior abdominopelvic CT scanning is the ability to detect renal parenchymal injury. In these patients, intravenous urography is not necessary, as it commonly is with traditional retrograde cystography.
A few studies have focused on delayed evaluation of the bladder. For example, the use of contrast material for chest and abdominal CT scanning (for which a large amount of contrast material is routinely required) has been studied. In these examinations, the contrast agent was allowed to distend the bladder in an anterograde fashion. However, in such cases this distention occurs at the expense of valuable time, because the Foley catheter should be clamped for at least 20-30 minutes to have any opportunity to achieve accurate results. Furthermore, if preexisting renal insufficiency or renal pedicle injury is present, this method may be inadequate.
The author does not recommend this diagnostic strategy for the reasons mentioned. Because study results have also cast doubt on the consistent accuracy of this method in the evaluation of blunt trauma, its use is discouraged.
Limitations of Techniques
Cystography generally has served to greatly decrease trauma morbidity and mortality by helping to successfully screen for bladder rupture. Little doubt exists concerning the accuracy of plain film cystography, as long as a bladder hematoma does not occlude a rift in the bladder wall and prevent dye from flowing out into the surrounding spaces. The primary concern is that the examination often does not occur in parallel with other radiologic examinations of patients with trauma who require CT scanning.
A caveat should be noted: a normal cystogram finding does not exclude a bladder rupture. At surgery, intraperitoneal or extraperitoneal extravasation may be found. The consideration in this scenario is the spasm of the detrusor muscle, which is possibly secondary to the irritation effect of the contrast medium, which causes a leak to become sealed. With general anesthesia, the detrusor relaxes; this is associated with the eventual intraoperative leak.
CT cystography is faster than are plain radiographic studies; moreover, it has no labor-intensive requirements for completion, and it can be used to diagnose large hematomas of the bladder, which potentially could overlie an occult breech in the bladder wall. Furthermore, classification of bladder injury patterns requires CT scanning because cystography addresses perforations but not more subtle findings.
The cost in each prospective hospital should be considered, because the monetary costs, which favor classic cystography, may not reflect actual benefits. For instance, because radiographic technologists currently are in short supply, increasing their use adds to the expense. Furthermore, time is valuable in the trauma setting, especially because patients in seemingly stable conditions can deteriorate quickly, and a more rapid evaluation can facilitate their transfer to the trauma intensive care unit or operating room. In general, the author believes that evaluation with CT cystography is the study of choice when patients already require transfer to the radiology suite for CT scanning evaluation. This is true especially when microscopic hematuria is present and a possibility of renal trauma exists.
Differential Diagnoses
Lumbar Spine, Trauma
Urethra, Trauma
Other Problems to Be Considered
Renal trauma, especially if hematuria is present
Ureteral trauma, especially if hematuria is present
Urethral trauma, especially if gross hematuria is present
Pelvic fractures
Lumbar spinal trauma, especially if lap-belt ecchymosis is present
Ruptured uterus
Bowel or mesenteric contusion
Ascites, frequent cause of low-density intraperitoneal fluid
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References
Brewer ME, Wilmoth RJ, Enderson BL, et al. Prospective comparison of microscopic and gross hematuria as predictors of bladder injury in blunt trauma. Urology. Jun 2007;69(6):1086-9. [Medline].
Quagliano PV, Delair SM, Malhotra AK. Diagnosis of blunt bladder injury: A prospective comparative study of computed tomography cystography and conventional retrograde cystography. J Trauma. Aug 2006;61(2):410-21; discussion 421-2. [Medline].
Sivit CJ, Taylor GA, Newman KD. Safety-belt injuries in children with lap-belt ecchymosis: CT findings in 61 patients. AJR Am J Roentgenol. Jul 1991;157(1):111-4. [Medline].
Tayal VS, Nielsen A, Jones AE, et al. Accuracy of trauma ultrasound in major pelvic injury. J Trauma. Dec 2006;61(6):1453-7. [Medline].
Nachshen S, Abusaid D, Nauta M, Govind A, Yoong W. The "catheter bag" sign revisited: a simple way detecting bladder trauma during operative laparoscopic procedures. Arch Gynecol Obstet. Jan 2008;277(1):65-6. [Medline].
Corriere JN Jr, Sandler CM. Diagnosis and management of bladder injuries. Urol Clin North Am. Feb 2006;33(1):67-71, vi. [Medline].
Morgan DE, Nallamala LK, Kenney PJ. CT cystography: radiographic and clinical predictors of bladder rupture. AJR Am J Roentgenol. Jan 2000;174(1):89-95. [Medline]. [Full Text].
Kim FJ, Chammas MF Jr, Gewehr EV, Campagna A, Moore EE. Laparoscopic management of intraperitoneal bladder rupture secondary to blunt abdominal trauma using intracorporeal single layer suturing technique. J Trauma. Jul 2008;65(1):234-6. [Medline].
Rapp DE, Corman JM. Conservative management of iatrogenic bladder injury with foreign body. Int Urogynecol J Pelvic Floor Dysfunct. Sep 2008;19(9):1319-21. [Medline].
Albala DM, Richardson JR Jr. Diagnosis and treatment of bladder rupture: characteristics of 42 cases. R I Med J. Mar 1991;74(3):133-7. [Medline].
Baniel J, Schein M. The management of penetrating trauma to the urinary tract. J Am Coll Surg. Apr 1994;178(4):417-25. [Medline].
Bodner DR, Selzman AA, Spirnak JP. Evaluation and treatment of bladder rupture. Semin Urol. Feb 1995;13(1):62-5. [Medline].
Burbridge BE, Groot G, Oleniuk FF. Emergency excretory urography in blunt abdominal trauma. Can Assoc Radiol J. Oct 1991;42(5):326-8. [Medline].
Chan L, Nade S, Brooks A. Experience with lower urinary tract disruptions associated with pelvic fractures: implications for emergency room management. Aust N Z J Surg. Jun 1994;64(6):395-9. [Medline].
Dawson C, Whitfield H. ABC of urology. Urological trauma and bladder reconstruction. BMJ. May 25 1996;312(7042):1352-4. [Medline]. [Full Text].
Deck AJ, Shaves S, Talner L. Computerized tomography cystography for the diagnosis of traumatic bladder rupture. J Urol. Jul 2000;164(1):43-6. [Medline].
Fishman EK, Horton KM. CT evaluation of bladder trauma: a critical look. Acad Radiol. May 2000;7(5):309-10. [Medline].
Haas CA, Brown SL, Spirnak JP. Limitations of routine spiral computerized tomography in the evaluation of bladder trauma. J Urol. Jul 1999;162(1):51-2. [Medline].
Pao DM, Ellis JH, Cohan RH. Utility of routine trauma CT in the detection of bladder rupture. Acad Radiol. May 2000;7(5):317-24. [Medline].
Peng MY, Parisky YR, Cornwell EE 3rd. CT cystography versus conventional cystography in evaluation of bladder injury. AJR Am J Roentgenol. Nov 1999;173(5):1269-72. [Medline].
Rehm CG, Mure AJ, O'Malley KF, et al. Blunt traumatic bladder rupture: the role of retrograde cystogram. Ann Emerg Med. Aug 1991;20(8):845-7. [Medline].
Sandler CM, Goldman SM, Kawashima A. Lower urinary tract trauma. World J Urol. 1998;16(1):69-75. [Medline].
Sivit CJ, Cutting JP, Eichelberger MR. CT diagnosis and localization of rupture of the bladder in children with blunt abdominal trauma: significance of contrast material extravasation in the pelvis. AJR Am J Roentgenol. May 1995;164(5):1243-6. [Medline].
Skinner EC, Parisky YR, Skinner DG. Management of complex urologic injuries. Surg Clin North Am. Aug 1996;76(4):861-78. [Medline].
Vaccaro JP, Brody JM. CT cystography in the evaluation of major bladder trauma. Radiographics. Sep-Oct 2000;20(5):1373-81. [Medline]. [Full Text].
Werkman HA, Jansen C, Klein JP. Urinary tract injuries in multiply-injured patients: a rational guideline for the initial assessment. Injury. Nov 1991;22(6):471-4. [Medline].
Williams MJ, Clancy MJ. Use of retrograde urethrography in the resuscitation room. Arch Emerg Med. Sep 1991;8(3):223-4. [Medline].
Further Reading
Keywords
bladder trauma, bladder injury, bladder pain, bladder rupture, bladder contusion, urinary tract injury, bladder symptoms, bladder injury in pelvic trauma, bladder insult, urologic injury in pelvic fractures
