A urethral injury is suspected when there is blood at the meatus, a Foley catheter cannot be passed, there is perineal bruising, or due to inability to void. Pelvic fractures are associated with urethral injuries around 10% of the times. Clinically, decisions have to be made regarding what diagnostic or interventions are needed for the patient.
The AUA Urotrauma guideline, recommends to always to do a retrograde urethrogram (RUG) when there is blood at the urethral meatus. If the RUG shows a partial urethral injury, a single attempt at urethral catheterization can be tried by someone experienced.
The recommended technique for the RUG consists of positioning the patient obliquely, lower leg bent at the knee and upper leg straight. An appropriate size catheter is advanced into the fossa navicularis and the balloon inflated with 1-2 ml. The penis is stretched by wrapping a long piece of gauze around the head of the penis and tying it under the glans, using the length of the gauze as a handle to keep the penis straight while injecting the contrast.
The guidelines do not address whether a RUG should be done when there is no blood but there is high likelihood of urethral injury — due to bruising, pelvic fracture, etc. The main thing in these situations is that if a Foley is attempted first, it has to be done by someone experienced and just one single try.
If unable to pass a catheter or when not advisable — due to complete urethral disruption on the RUG–, a suprapubic tube is placed ASAP.
With posterior urethral injuries in hemodynamically stable patients, endoscopic primary realignment (PR) can be attempted to get a urethral catheter across the injury and allow the urethra to heal in alignment. Patients who had PR tend to have less severe strictures.
For PR, 2 urologists and 2 sets of cystoscopes and monitors are needed. One urologist scopes the urethra and the other one approaches the injury from the suprapubic tract. Using vision, xrays, and glidewires, the urethra is aligned over a catheter. PR is best done in the first few days after the injury, once the patient is stable, in the operating room, and under anesthesia. The urotrauma guideline recommends against prolonged and heroic attempts at PR.
Who needs immediate surgery?
- All female urethral injuries should be primarily repaired. The AUA Urotrauma guideline does not discuss female urethral injuries, however, the European trauma guideline does, as well as the free online: Guideline of guidelines: a review of urological trauma guidelines.
- Penetrating anterior urethral injuries.
Female urethral injury case study
A 4-year-old girl came to the ER after her father backed his pick up truck at slow speed over her hip area while she was playing close to the truck. She had blood coming from the introitus. A catheter was passed by the trauma team:
The patient was taken to the OR for definitive repair. This is what it was found:
- Distal 1-2 cm of the urethra was intact
- The proximal urethra/bladder neck was floating completely separated from the bladder and the distal urethra.
- There was a laceration of the anterior vagina extending from under the distal urethra to almost the cervix.
An adult urologist, pediatric urologist, and pediatric surgeon tackled the repair retropubically. The vagina was closed first followed by re-anastomosis of the distal and proximal urethra and lastly the proximal urethra/bladder neck and the bladder.
One year after the injury the patient was voiding normally with no accidents day or night and with a normal renal ultrasound. There is no way the same outcome could have been achieved without surgery. This case illustrates the importance of primary repair of urethral injuries in girls.
A urethral injury is suspected when there is blood at the meatus, in which case a retrograde urethrogram is mandatory to assess the injury and decide on bladder drainage. When there is no blood at the meatus but a urethral injury is suspected because of pelvic fracture, perineal hematoma or difficulty voiding, it never hurts to do a RUG, although a single attempt a catheterization of the urethra by someone experienced might be reasonable.
For posterior urethral injuries, a short attempt at primary realignment in the first few days after the injury might help reduce the severity of the stricture.
It is imperative to primarily repair urethral injuries in girls and avoid any attempts at catheter alignment.