T. J. Herron1, J. Chipko1, S. Dosal1, S. Lorch1, D. J. Ciesla1 1University Of South Florida College Of Medicine,Division Of Trauma & Acute Care Surgery,Tampa, FL, USA
Introduction: Bladder injury is a rare but serious complication of pelvic fractures. Diagnosis usually requires CT cystography, however, scanning all patients with pelvic fractures is inefficient and increases radiation exposure. The purpose of this study was to identify associated clinical findings to guide a selective approach to diagnostic imaging in blunt trauma patients with pelvic fractures.
Methods: Adult (Age>18) Trauma patients with pelvic fractures at a Level 1, academic medical center were retrospectively reviewed from a prospective database over a three-year period. All patients underwent an initial CT of the abdomen and pelvis as well as a microscopic urinalysis as part of their initial trauma evaluation. An arbitrary cut off of microscopic hematuria was designated as >100 RBC per high power field (HPF). Patients who had a penetrating mechanism as well as those who did not have both components of the aforementioned evaluation were excluded.
Results: A total of 434 patients were reviewed. Of these, 120 patients met exclusion criteria, for a sample size of 314 patients. There were no identified bladder injuries in the 231 patients with microscopic hematuria <100 RBC per HPF (NPV=100%). Nine bladder injuries (2.87%) were identified in the 83 patients with microscopic hematuria >100 RBC per HPF; two of the 83 patients with microscopic hematuria >100 RBC per HPF, but without gross hematuria, had bladder injuries (NPV=96%). Six of the bladder injuries were extraperitoneal and treated with bladder decompression alone. Three of the bladder injuries were intraperitoneal ruptures requiring operative intervention. All patients with bladder injuries had high energy transfer mechanisms with anteroposterior compression and lateral compression fracture patterns being most common. The mean ISS of patients without a bladder injury [n=305] was 18.24 vs. 27.44 in patients with a bladder injury [n=9] (p=0.029) 95% CI [0.91, 17.51]
Conclusion: In trauma patients presenting with pelvic fractures, a microscopic hematuria of <100 RBC per HPF excludes bladder injury (NPV=100%). In patients without gross hematuria, a selective use of CT cystogram in the evaluation of bladder injury can be applied to patients with higher energy transfer mechanisms resulting in pelvic fractures.