RECTOURETHRAL FISTULAS (RUF)
Etiology: congenital (i.e. imperforate anus) and acquired
- Iatrogenic rectal injury during pelvic surgery
- Anterior rectal wall biopsy
- Inflammatory or infectious conditions
- Radiation: brachytherapy or external beam radiation
Most common causes of RUF: prostatectomy and CaP radiation
- Incidence of rectal injury at time of radical prostatectomy = 0.5% and 9%.
- Incidence using laparoscopic or robotic access = 1% to 2.7%.
- Success of RUF repair in cases of radiation injury and Crohn’s disease tends to be lower than in patients with other causes of RUF.
Management of Intraoperative Rectal Injury
- Primary repair if the operative field is clean
- Diverting colostomy if the field is contaminated.
- Rectal injury from thermal energy
- Rarely recognized intraoperatively
- Usually presents a week later as rectal bleeding or sepsis.
- Resuscitation, immediate diversion with drainage of abscess, and supportive care
- Si/Sx: pneumaturia, fecaluria, rectal bleeding, rectal voiding, leakage or watery diarrhea, severe rectal and pelvic pain.
- May present with life-threatening bleeding, intra-abdominal abscess, sepsis, and necrotizing fasciitis, particularly if the diagnosis is delayed.
- When a fistula recurs after initial surgical repair, patient is rarely acutely ill.
- Recurrent UTIs: common complaint in chronic RUF patients.
Diagnosis, Evaluation, Preparation
- CT of the abdomen and pelvis in cases of sepsis and suspected abscess
- Diagnostic studies should be postponed in the presence of fever or sepsis and undertaken only after proximal urinary diversion, administration of intravenous antibiotics, and resolution of the acute process.
- RUG and VCUG, cystoscopy, proctoscopy, and EUA
- Helps determine extent of radiation damage surrounding the fistula, fistula size and location, rectal sphincter condition, and evidence of associated urethral or bladder neck stricture
- Assess bladder capacity
- FUDS: when the bladder is extremely contracted or fibrotic, preservation of the bladder is not likely to provide a functional outcome.
- RUFs are commonly debilitating and resistant to repeated repair procedures.
- Need careful preoperative staging evaluation.
- Fecal and urinary diversion should be performed in most cases before any definitive repair.
- Diversion of fecal and urinary streams from the fistula allows inflammation to improve or resolve before repair.
- Diversion alone is sufficient therapy to allow a small, non-radiated fistula to heal in approximately 20% to 25% of cases.
- After fecal diversion (colostomy or ileostomy) and urinary diversion (SP tube, or rarely ileal conduit), a waiting period of 3 to 9 months is common.
- Allows inflammation and infection to heal; in a small percentage of iatrogenic cases the fistula may resolve spontaneously.
- Surgical Principles:
- First attempt at closure is the best attempt.
- Judicious use of tissue interpositions in the plane between the rectum and the urethra is recommended: omentum, gracilis muscle, sartorius muscle, and buccal mucosal grafts may be used.
- Buccal mucosal graft can be placed over the prostatic urethral defect at the time of repair to decrease the incidence of urinary extravasation.
- Surgical approach:
- Some urologists favor a posterior or perineal approach.
- Perineal approach is familiar and favors use of dartos or gracilis tissue flaps.
- Disadvantages include a theoretical risk of impotence, limited exposure, and the possible presence of significantly scarred tissues.
- Anterior transanorectal approach provides good exposure and also easily allows use of dartos, gracilis, or
rectal tissue flaps for interposition.
- Rectal sphincter muscles may be divided, but anatomic repair can maintain fecal continence.
Complications associated with the surgical repair of RUF
- Bleeding, wound infection, and early or late recurrence of the fistula.
- Oral antibiotics
- Cystogram at 3 weeks.