Preventing urinary tract injury at the time of hysterectomy

Hysterectomy remains the most common gynecologic procedure in the United States; approximately 600,000 hysterectomies are performed each year, the majority of which are for benign disease.¹ Minimally invasive approaches to hysterectomy have well-documented advantages, yet abdominal hysterectomy remains the most common mode of access, accounting for more than 60% of all hysterectomies performed in the United States as of 2005.^1,2

Despite the frequency with which hysterectomy is performed, urinary tract injury is not uncommon given the intimate relationship between the genital and urinary tracts.³ The various approaches to hysterectomy are accompanied by differing rates of urinary tract injury,^{4, 5} but the combined incidence of such events during procedures for benign disease is as high as 4.3% to 4.8%.^5,6

With regard to mode of hysterectomy, vaginal hysterectomy is reported to have a lower incidence of ureteral injury when compared with abdominal hysterectomy (0.9% vs 1.7%, although the differences did not reach statistical significance). Notably, the rate of ureteral injury did increase to 2.6% when vaginal hysterectomy was performed concomitant with pelvic floor reconstruction.⁵

Illustration by Alex Baker, DNA Illustrations, Inc.

More data have also become available on rates of urinary tract injury with laparoscopy as this approach has gained wider acceptance. In one of the first studies comparing incidence of ureteral injury in a Finnish cohort, incidence of injury was as high as 13.9 in 1000 for laparoscopic hysterectomy, versus 0.4 in 1000 for abdominal and 0.2 in 1000 for vaginal hysterectomies.⁷ However, in a follow-up study, incidence of ureteral injuries was 3.4 in 1000, a significant decrease that may be attributable to the learning curve associated with laparoscopic hysterectomy.⁸ Recent data do support a higher rate of recognized ureteral injury during total laparoscopic hysterectomy compared with other methods, including laparoscopic supracervical hysterectomy.^9-11

In the same initial Finnish cohort, incidence of bladder injury was higher in the abdominal hysterectomy group than in the vaginal or supracervical hysterectomy groups (1.3 vs 0.2 and 0.3 in 1000), but incidence of injury was highest with the laparoscopic approach (8.9 in 1000).⁷ The follow-up to this initial study also demonstrated a higher incidence of bladder injury with laparoscopic hysterectomy (3.4 in 1000).⁸ Notably, no significant difference has been shown with regard to incidence of bladder injuries for total versus subtotal laparoscopic hysterectomy.¹¹

The eVALuate study was a 2-part, randomized controlled trial that examined outcomes with laparoscopic hysterectomy versus abdominal hysterectomy and laparoscopic hysterectomy versus vaginal hysterectomy.¹² In both arms of the trial, bladder injuries were encountered in all forms of hysterectomy, though ureteral injuries were noted only in laparoscopic hysterectomy cases. Laparoscopic hysterectomy was associated with a significantly higher rate of all major complications (including urinary tract injuries) than was abdominal hysterectomy. Although this difference was not detected in the vaginal hysterectomy arm of the trial, it was underpowered to detect such a difference.

In terms of mode of access for hysterectomy, gynecologic surgeons’ familiarity with vaginal and abdominal approaches may explain the favorable rates of urinary tract injury associated with these procedures. Laparoscopic hysterectomy, however, is being performed more frequently due to advantages in minimizing blood loss, reducing length of hospital stay and decreasing postoperative pain and time to recovery.

As surgeons progress on the learning curve and gain increased proficiency with laparoscopic hysterectomy, it is likely that rates of urinary tract injury will decrease. This article outlines strategies for successfully minimizing risk of urinary tract injury during hysterectomy, regardless of the operative approach.

Strategy 1: Possess knowledge of the anatomy

Detailed knowledge of pelvic anatomy is essential to avoid injury to the ureter or bladder during hysterectomy. With regard to bladder injury, the dome of the bladder is commonly involved in injury during total hysterectomy. The bladder neck is at most risk during vaginal hysterectomy or reconstructive surgeries of the anterior vaginal wall. The most common sites of ureteral injury are at the pelvic brim, near the infundibulopelvic ligament (Figure 1), and deeper in the pelvis, as it courses by the uterosacral ligament under the uterine artery approaching the cardinal ligaments (Figure 2).

When considering the course of the ureter,

division into abdominal and pelvic portions allows for ease of identification of neighboring structures.¹³ The ureter is 25 cm to 30 cm long, and its sources of perfusion vary as it passes from the abdomen into the pelvis. Notably, the right ureter is approximately 1 cm longer than the left ureter,¹⁴ but whether that has clinical significance for operative planning remains unclear.

In the abdomen, the ureter overlies the psoas muscle, receiving its perfusion in part from the renal vessels and common iliac.¹⁵ Mobilization of the colon and its mesentery allows access to the retroperitoneum and visualization of the ureter. Before entering the true pelvis, the gonadal vessels cross the ureter anteriorly and provide a perfusing branch. Given the close proximity to the gonadal vessels, isolation and identification of the ureter is imperative to minimize risk of transection during adnexal surgery. At the pelvic brim, the ureter passes over the bifurcation of the common iliac arteries and is ensheathed in connective tissue.

The ureter continues to course in the medial leaf of the broad ligament, and remains medial to the internal iliac arteries on the posterolateral pelvic sidewall.¹⁵ It then passes under the uterine artery through the cardinal ligament, before proceeding anterolaterally, approximately 1 cm to 1.5 cm from the cervix. There, the ureter lies along the anterior vaginal wall, separated from the wall of the bladder by 1.5 cm, before opening into the bladder trigone.

This course in the deep pelvis necessitates isolation and lateralization of the ureter in cases of total or radical hysterectomy in order to avoid injury. Nearly 80% of ureteral injuries occur in close proximity to the uterine artery.⁵ The bladder trigone and bladder base are also at risk of injury in the deep pelvis. The trigone rests over the anterior bladder fornix and the bladder base rests on the lower uterine segment and cervix (Figure 3).^13,16

Strategy 2: Address patient-specific risk factors

In addition to knowledge of the anatomy and meticulous dissection, preoperative planning is essential to minimize risk of urinary tract injury. Half of all patients who sustain a ureteral injury have no identifiable risk factors, but if patient-specific issues are identified, additional imaging studies or alterations in the surgical plan can be considered to mitigate risk.¹⁴

Risk of injury to the urinary tract is higher in procedures for invasive cancer or urogynecologic surgery.¹⁴ Ten percent of patients undergoing hysterectomy for known cervical pathology (such as a mass or tumor) will have a ureter within
5 mm of the cervical tissue.¹⁷ In these individuals, preoperative imaging may be helpful for surgical planning in an attempt to minimize risk of ureteral injury.

Pelvic anatomy also may be distorted in association with particular clinical scenarios. For example, pelvic adhesive disease may be the initial barrier to visualizing and isolating pertinent anatomy in patients with a history of abdominopelvic surgery, pelvic radiation, pelvic infections or advanced endometriosis. In such cases, sharp dissection is preferable to blunt dissection or use of thermal instruments to minimize risk of injury in the setting of compromised anatomic planes.

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Multiple cesarean deliveries are also associated with an increased risk of pelvic adhesive disease,¹⁸ and difficulty with bladder dissection during subsequent gynecologic surgery can be expected. The bladder dome, adhesed to the lower uterine segment, requires meticulous dissection to avoid injury; cystotomy occurs in greater than 20% of women with more than 3 prior cesarean deliveries.¹⁹ Specific to endometriosis, fibrosis of the uterosacral ligament can draw the ureter medially at this location, placing the ureter at high risk of injury during dissection in the posterior cul-de-sac.²⁰

Patients undergoing hysterectomy for large uteri or who require resection of adnexal masses are also at increased risk of ureteral injury.²¹ This may be related to anatomic distortion and engorgement of the vasculature, which can make identification of the anatomic course of the ureter challenging. Less commonly, ectopic insertion of the ureter or duplication in the renal system puts a patient at increased risk of ureteral injury.²¹ Although preoperative imaging would aid in surgical planning, such anomalies are often identified intraoperatively and the surgeon should have a high degree of suspicion when dissection reveals an anatomic variant.

Figure copyright 2007 BJU International. Used with permission from John Wiley and Sons.

Ureteral catheterization prior to hysterectomy has been proposed in high-risk populations and has also been investigated as universal preoperative prophylaxis. In both a retrospective study and randomized trial, use of catheterization resulted in no significant difference in incidence of ureteral injury.^22,23 In Kuno’s retrospective study,²² all injuries occurred in patients undergoing laparotomy for malignancy or leiomyomata (although uterine size was not disclosed).

A separate retrospective study found a decreased incidence of ureteral injury with preoperative stent placement, in addition to a cost savings in terms of operative time related to identification of the ureter.²⁴ This cost savings may be attributable to decreased operative time if anatomic deviations were corrected by straightening the ureter’s course.²³ Based on these findings, we suggest that prophylactic ureteral catheterization should not be a substitute for meticulous dissection, but in an appropriately selected patient it may improve the ability to identify the ureter either visually or by palpation. The decision about use of catheterization should be left to the surgeon’s discretion.

Strategy 3: Screen for injury

Minimizing the risk of intraoperative injury requires maintaining visual identification of the ureters and bladder in relation to the operative target. This also allows early recognition of injury, should it occur. Confirmatory measures for further reorientation include palpation of the ureters and bladder, bladder back-filling, administration of intravenous (IV) dye, cystoscopy, and retrograde pyelography.

During abdominal and vaginal hysterectomy, the ureter can be palpated and elevated to confirm its course. During vaginal hysterectomy, the ureter can be palpated between the infundibular and hypogastric artery pulses. This may not always be possible, however, if a surgeon cannot readily appreciate this subtle anatomic landmark intraoperatively.

During abdominal and laparoscopic hysterectomy, when the retroperitoneum is opened with division of the round ligament, the ureter can be visually identified on the medial leaf of the broad ligament. Observation of ureteral peristalsis allows for visual identification of the ureter’s course through the deep pelvis, although this alone should not be viewed as confirmation of ureteral integrity as peristalsis may occur despite injury.⁶

In patients with extensive pelvic adhesive disease (i.e. advanced-stage endometriosis, history of prior pelvic procedures, history of pelvic radiation), visual identification or palpation of the ureter may be impossible even after careful dissection; in these cases a full ureterolysis may be necessary. If oophorectomy is undertaken alone or at the time of hysterectomy, opening the retroperitoneum surrounding the infundibulopelvic (IP) ligament on the pelvic sidewall allows the surgeon to “peel” the retroperitoneum and IP ligament medially so that the ureter can be seen coursing inferio-posteriorly to this dissection.

Many surgeons place a uterine manipulator at the start of laparoscopic hysterectomy. Although a variety of manipulators are available, many have a cervical cup or ring. With cephalad pressure, the cup or ring should be well applied to the vaginal fornices, which provides an important intraoperative landmark. The cephalad pressure allows for palpation of the ring intra-abdominally, identifying the level at which the colpotomy should be performed. When cephalad pressure is applied during colpotomy, the previously ligated uterine vascular pedicle and ureter fall away from the colpotomy incision and remain lateral to the vaginal cuff during closure (Figure 4).

Intraoperatively, limiting blunt dissection of the tissue planes surrounding the bladder is paramount to minimize risk of bladder injury.¹³ In cases where suspicion is high for a bladder injury, backfilling the bladder with saline or dilute indigo carmine solution can help assess integrity of the lower urinary tract by revealing leakage at the site of damage. Intravenous administration of indigo carmine with subsequent efflux of blue fluid from the site of injury can reveal occult ureteral transection. In addition, during a laparoscopic procedure, the Foley catheter bag may fill with gas in cases of cystotomy.

Regardless of the surgical approach, careful closure of the vaginal cuff is warranted in cases of total hysterectomy. Anchoring the vaginal cuff to the uterosacral ligament pedicle is commonly practiced as a mode to support the vaginal apex, but the surgeon must take care to avoid an anchoring stitch lateral to the cuff margins so as not to run the risk of incorporating the ureter into the closure.

Immediately following the procedure, cystoscopy can be used as a surveillance technique to assess both bladder and ureter integrity. In a study based on universal cystoscopy at the time of hysterectomy, rate of detection of urinary tract injury pre-cystoscopy was found to be approximately 25.6%, with improvement to 97.4% detection once cystoscopy was employed. Importantly, 75% of injuries detected on cystoscopy were previously unsuspected.⁵

It should be noted that visualization of bilateral ureteral jets immediately post-hysterectomy does not guarantee ureteral integrity as this may not reveal thermal injuries, kinking, or stricture of the ureters. Despite these limitations, the American Association of Gynecologic Laparoscopists currently recommends that routine cystoscopy be considered at the time of total laparoscopic hysterectomy, although data are insufficient to extend the recommendation to laparoscopic subtotal hysterectomy.⁴

At the start of cystoscopy, information about bladder integrity is obtained, as inability to adequately distend the bladder often indicates that cystotomy has occurred. A full bladder survey is then performed, with special attention to areas near the surgical dissection, such as the bladder dome or base. Intravenous administration of dye (indigo carmine is preferred, given the small but appreciable risk of methemoglobinemia with use of methylene blue) aids in visualization of the efflux of urine from the ureteral orifices. Sluggish or absent efflux of urine from the ureteral orifices is often a sign of ureteral injury.

Cystoscopy is a useful screening tool, but does have its limitations. A recent retrospective study from our institution based on selective (rather than universal) cystoscopy found that no intraoperative bladder injuries were diagnosed using cystoscopy. Additionally, cystoscopy was normal in 50% of patients who had a postoperative diagnosis of cystotomy.²⁵ These limitations are particularly important in the case of laparoscopic hysterectomy, which commonly involves dissection and vessel sealing with electrosurgical devices. Damage due to thermal injury may be delayed in onset by 10 to 14 days, and as such is generally not detected on intraoperative cystoscopy or immediate postoperative imaging.^25,26 As mentioned above, normal ureteral efflux is also not a guarantee of ureteral integrity in cases of partial obstruction. Although cystoscopy may be a useful adjunct to aid in detection of bladder or ureteral injury, it should not be considered a substitute for proper surgical technique and intraoperative visualization and isolation of these structures.

Strategy 4: Recognize the injury

Delayed identification of urinary tract injury can result in poor outcomes with long-standing sequelae such as compromised or lost renal function. Intraoperative or postoperative consultation with a urologist is recommended and may be necessary in complex cases, even when the gynecologic surgeon is capable of ureteric or bladder repair. The approach to immediate repair is dependent on the type of injury, with crush or thermal injuries requiring resection of the damaged segment. In cases of delayed diagnosis, placement of a nephrostomy tube may be required as a temporizing measure prior to definitive repair.

Postoperatively, a high degree of suspicion is required to identify patients with urinary tract injuries unrecognized at the time of surgery. Patients may present with a wide range of complaints, depending on the time since the primary surgery. Symptoms may include flank pain or costovertebral angle tenderness, fever, ileus, peritonitis, anuria,²⁷ or frank fistula.^28,29 Computed tomography imaging aids in postoperative diagnosis of urinary tract injury by its ability to detect intra-abdominal extravasation of urine.²⁸ Fluoroscopic retrograde ureterography and urogram with IV contrast are additional methods of identifying urinary tract patency postoperatively.²⁹

Summary

Urinary tract injury is a known complication of hysterectomy, regardless of route of procedure. Surgeon familiarity and comfort with complex anatomy, as well as preoperative risk stratification, is essential to minimizing risk of urinary tract injury. Intraoperative assessment of ureter and bladder integrity is the first step in preventing delayed diagnosis of injury. Although a useful adjunct, cystoscopy does not identify all injuries. A high index of suspicion postoperatively with appropriate imaging will promote early diagnosis of intraoperative injuries. Consultation with an advanced gynecologic surgeon
and/or urologist is recommended when definitive repair intraoperatively is possible. Postoperative repair of injury may require additional interventions prior to corrective surgery. 

References

1. Wu JM, Wechter ME, Geller EJ, Nguyen TV, Visco AG. Hysterectomy rates in the United States, 2003. Obstet Gynecol. 2007;110(5):1091-1095.

2. Jacoby VL, Autry A, Jacobson G, Domush R, Nakagawa S, Jacoby A. Nationwide use of laparoscopic hysterectomy compared with abdominal and vaginal approaches. Obstet Gynecol. 2009;114(5):1041-1048.

3. Liapis A, Bakas P, Giannopoulos V, Creatsas G. Ureteral injuries during gynecological surgery. Int Urogynecol J Pelvic Floor Dysfunct. 2001;12(6):391-393.

4. American Association of Gynecologic Laparoscopists (AAGL). AAGL practice report: practice guidelines for intraoperative cystoscopy in laparoscopic hysterectomy. J Minim Invasive Gynecol. 2012;19(4):407-411.

5. Ibeanu OA, Chesson RR, Echols KT, Nieves M, Busangu F, Nolan TE. Urinary tract injury during hysterectomy based on universal cystoscopy. Obstet Gynecol. 2009;113(1):6-10.

6. Vakili B, Chesson RR, Kyle BL, et al. The incidence of urinary tract injury during hysterectomy: a prospective analysis based on universal cystoscopy. Am J Obstet Gynecol. 2005;192(5):1599-1604.

7. Härkki-Sirén P, Sjöberg J, Tiitinen A. Urinary tract injuries after hysterectomy. Obstet Gynecol. 1998;92(1):113-118.

8. Brummer TH, Seppälä TT, Härkki PS. National learning curve for laparoscopic hysterectomy and trends in hysterectomy in Finland 2000-2005. Hum Reprod. 2008;23(4):840-845.

9. Jelovsek JE, Chiung C, Chen G, Roberts SL, Paraiso MF, Falcone T. Incidence of lower urinary tract injury at the time of total laparoscopic hysterectomy. JSLS. 2007;11(4):422-427.

10. Gilmour DT, Das S, Flowerdew G. Rates of urinary tract injury from gynecologic surgery and the role of intraoperative cystoscopy. Obstet Gynecol. 2006;107(6):1366-1372.

11. Donnez O, Jadoul P, Squifflet J, Donnez J.A series of 3190 laparoscopic hysterectomies for benign disease from 1990 to 2006: evaluation of complications compared with vaginal and abdominal procedures. BJOG.2009;116(4):492-500.

12. Garry R, Fountain J, Mason S, et al. The eVALuate study: two parallel randomised trials, one comparing laparoscopic with abdominal hysterectomy, the other comparing laparoscopic with vaginal hysterectomy. BMJ. 2004;328(7432):129.

13. Utrie JW Jr. Bladder and ureteral injury: prevention and management. Clin Obstet Gynecol. 1998;41(3):755-763.

14. Chan JK, Morrow J, Manetta A. Prevention of ureteral injuries in gynecologic surgery. Am J Obstet Gynecol. 2003;188(5):1273-1277.

15. Rock JA Jr, Jones HW. TeLinde’s Operative Gynecology. 10th ed. Philadelphia, PA: Lippincott Williams, & Wilkins; 2008.

16. Fröber R. Surgical anatomy of the ureter. BJU Int 2007;100(4)949-965.

17. Gemer O, Simonovsky A, Huerta M, Kapustian V, Anteby E, Linov L. A radiological study on the anatomical proximity of the ureters and the cervix. Int Urogynecol J Pelvic Floor Dysfunct. 2007;18(9):991-995.

18. Tulandi T, Agdi M, Zarei A, Miner L, Sikirica V. Adhesion development and morbidity after repeat cesarean delivery. Am J Obstet Gynecol. 2009;201(1):56.e1-56.e6.

19. Wang L, Merkur H, Hardas G, Soo S, Lujic S. Laparoscopic hysterectomy in the presence of previous caesarean section: a review of one hundred forty-one cases in the Sydney West Advanced Pelvic Surgery Unit. J Minim Invasive Gynecol. 2010;17(2):186-191.

20. Frenna V, Santos L, Ohana E, Bailey C, Wattiez A. Laparoscopic management of ureteral endometriosis: our experience. J Minim Invasive Gynecol. 2007;14(2):169-171.

21. Dandolu V, Mathai E, Chatwani A, Harmanli O, Pontari M, Hernandez E. Accuracy of cystoscopy in the diagnosis of ureteral injury in benign gynecologic surgery. Int Urogynecol J Pelvic Floor Dysfunct. 2003;14(6):427-431.

22. Kuno K, Menzin A, Kauder HH, Sison C, Gal D. Prophylactic ureteral catheterization in gynecologic surgery. Urology. 1998;52(6):1004-1008.

23. Chou MT, Wang CJ, Lien RC. Prophylactic ureteral catheterization in gynecologic surgery: a 12-year randomized trial in a community hospital. Int Urogynecol J Pelvic Floor Dysfunct. 2009;20(6):689-693.

24. Redan JA, McCarus SD. Protect the ureters. JSLS. 2009;13(2):139-141.

25. Sandberg EM, Cohen SL, Hurwitz S, Einarsson JI. Utility of cystoscopy during hysterectomy. Obstet Gynecol. 2012;120(6):1363-1370.

26. Wu HH,Yang PY, Yeh GP, Chou PH, Hsu JC, Lin KC. The detection of ureteral injuries after hysterectomy. J Minim Invasive Gynecol. 2006;13(5):403-408.

27. Visco AG, Taber KH, Weidner AC, Barber MD, Myers ER. Cost-effectiveness of universal cystoscopy to identify ureteral injury at hysterectomy. Obstet Gynecol. 2001;97(5 pt 1):685-692.

28. Gayer G, Hertz M, Zissin R. Ureteral injuries: CT diagnosis. Semin Ultrasound CT MR. 2004;25(3):277-285.

29. Kim JH, Moore C, Jones JS, et al. Management of ureteral injuries associated with vaginal surgery for pelvic organ prolapse.
Int Urogynecol J Pelvic Floor Dysfunct. 2006;17(5):531-535.