Current Ureteral Injury Guidelines

There is a paucity in the literature on how ureteral injuries from blunt external trauma are managed in the community. The European Association of Urology (EAU) annually updates their guidelines, and the AUA published Urotrauma guidelines in 2014 and amended them in 2020.^1,2 Though these provide a framework for the practicing urologist, ureteral injury is still a very uncommon occurrence, and much of the guidelines are formulated on low-level evidence/expert opinions. Additionally, the guidelines largely derive their data from penetrating or iatrogenic injury. It is therefore unsurprising that when John Doe rolls into your emergency department at 2 a.m. there may be some anxiety and uncertainty in the management of blunt traumatic ureteral injuries.

Traditionally, blunt traumatic ureteral injuries are secondary to falls from height or rapid deceleration, such as high-speed motor-vehicle accidents. Most often, these injuries occur secondary to back hyperextension at fixation points–primarily at the ureteropelvic junction and less frequently, the ureterovesical junction.

Based on current guidelines in managing ureteral injuries, ureteral reconstruction (UR)/repair is recommended in stable patients with severe injuries–ureteral lacerations/avulsions. The exception being hemodynamic instability, where these injuries may be initially managed by minimally invasive methods (ureteral stent, ligation or percutaneous nephrostomy), in the context of damage control polytrauma management. Here, definitive UR is delayed until the patient is stabilized. Low severity ureteral injuries can usually be successfully managed by ureteral stent placement and/or percutaneous nephrostomy. This seems simple enough, but are seasoned practicing urologists in the community following the guidelines, and does this matter?

Figure. Contemporary management patterns of blunt ureteral injury. ISS, Injury Severity Score. SBP, systolic blood pressure.

What the Data Say

We recently evaluated this question by utilizing the National Trauma Data Bank^®.³ During a 9-year period from 2007–2016, we found 147 blunt traumatic ureteral injuries, by far the largest reported series in the literature. We defined low severity ureteral injuries as contusions, hematoma or a minor laceration with no perforation. Severe ureteral injuries were massive lacerations, avulsions or ruptures, with tissue loss or transection. Of the 147 blunt ureteral injuries, 67% were unstable and 35% had a high severity ureteral injury. Urologists largely follow AUA/EAU ureteral guidelines and place a ureteral stent or nephrostomy tube when it comes to low-grade ureteral injuries for both stable and unstable patients. The data get interesting when it comes to high-grade ureteral injuries. Counterintuitively, high-grade injuries were mostly managed by minimally invasive approaches (like a nephrostomy tube) over a reconstructive procedure–83% vs 26.7%. Laparotomy for associated injuries resulted in a higher frequency of UR vs laparotomy for UR alone–27.3% vs 16.4% (see figure). This practice pattern mirrors the approaches advocated by Arlen⁴ and Ghali⁵ et al in prior published studies.

In other words, when the abdomen is open, urologists are more likely to repair blunt ureteral injuries surgically at the time of injury. For high-grade ureteral injuries (ie ureteropelvic junction avulsions) without laparotomy, urologists in practice favor nephrostomy as a method of damage control and delay definitive reconstruction to a later date.

Ureteral reconstruction, whether it be pyeloplasty, ureteroureterostomy, primary ureteral repair or ureteroneocystostomy, can be a technically challenging, invasive, time-consuming and a potentially morbid procedure. If UR is acutely needed, the on-call urologist will not be comfortable with an open repair. Thus, is it better to temporize and have a reconstructive trained urologist repair this injury in a delayed fashion? Trauma surgeon to urologist dynamics also may be at play here. Some institutions may not have easy access to a urologist to perform immediate UR. Also, trauma surgeons may not be consulting urologists during the acute management phase and only until well after patient stabilization or laparotomy. These factors may explain the high rate of conservative management.

Future Directions

Blunt ureteral trauma is a rare event, and there is a paucity of literature regarding ureteral injuries and outcomes of staged vs immediate repairs. Does a damage control approach for high-grade ureteral injury offer a bridge to a staged and successful UR? Is the efficacy and durability of a repair at the time of injury worse than a staged repair? We conjecture yes, but future studies are urgently needed.