UROGENITAL TRAUMA

Renal injury and operative management in the United States: results of a population-based study
Wessells H, Suh D, Porter JR, Rivara F, MacKenzie EJ, Jurkovich GJ, Nathens AB.
Department of Urology, Harborview Medical Center and University of Washington
Medical School, Seattle, 98104, USA
J Trauma. 2003; 54:423-30

• Background: To evaluate the extent to which nonoperative renal trauma management has been adopted, we determined the incidence of renal injury and the rate of operative management across the United States.
• Methods: International Classification of Diseases, Ninth Revision diagnosis and procedure codes identified patients with renal injuries in an 18-state administrative database representing 62% of the U.S. population.
• Results: Of 523,870 patients hospitalized for trauma in 1997 or 1998, 6,231 (1.2%) had renal injuries (4.89 per 100,000 population). Sixty-four percent of patients with injuries that were classified had contusions/hematomas, 26.3% had lacerations, 5.3% had parenchymal disruption, and 4% had vascular injuries. Eleven percent of renal trauma patients required surgical management of their kidney injuries, of whom 61%, or 7% of patients with renal injuries overall, underwent nephrectomy. Injury Severity Score, mechanism, and renal injury severity were independent predictors of nephrectomy.
• Conclusion: The nephrectomy rate in community and academic centers reflects renal and global injury severity. Prospective trials are indicated to determine whether, in the traumatized patient with severe kidney injury, renal preservation could lead to improved outcomes compared with nephrectomy.
  
  
• Editorial Comment
  The most quoted statistic is that 10% of all serious injuries involve the kidney. However, in this review of half a million American trauma patients, the real incidence was closer to 1%. Subset analysis showed different renal injury rates depending on the cause of trauma: firearms 3.5%, motor vehicle accidents 2.2%, bicycle accidents 1.9%, pedestrian accidents 1.5%, stab wound 0.8% and falls 0.5%. Most injuries were renal contusions (64%) although 26% had lacerations, 5% had parenchymal disruption and 4% had vascular injuries. 13% of lacerations were treated with renorrhaphy, and 10% with nephrectomy, while 25% of vascular injuries required nephrectomy.
  Patients with vascular injuries, when operated on, had an 84% nephrectomy rate - which seems understandable in light of the potential for exsanguination or renal nonfunction after these injuries. Of those being operated on for lacerations, the nephrectomy rate as an appallingly high 64%.
  There are lessons from this huge series:
  1) Renal injury rates are lower than we thought
  2) Vascular injuries, when operated on, usually result in nephrectomy
  3) Renal lacerations (too) frequently result in nephrectomy when operated on. Because of this, I believe that expectant management is the preferred approach, as surely some of these 64% lost kidney might be saved either by more judicious use of renorrhaphy or by avoiding retroperitoneal exploration altogether.

Dr. Richard A. Santucci
Assistant Professor of Urology
Wayne State University
Detroit, Michigan, USA