Complications of Mesh in Vaginal Surgery

In the US stress urinary incontinence and pelvic organ prolapse (bladder /vaginal descent) affects > 50% of women older than 50 years of age. (Subak OB Gyn; 2001) Eleven percent of women at least have 1 operation in their lifetime and 29 % require a second operation for prolapse. (Subak OB gyn 2001). This article is to discuss mesh placement for pelvic organ prolapse (POP) as well as for stress urinary incontinence (SUI). In light of many lawsuits and advertisements for such issues against the companies who have developed surgical procedures, a need to further discuss this situation with the public exists from a medical prospective as well.

The “bladder lift” also called cystocele repair is the single most common operation in this category. (Olsen, Ob Gyn; 1997) Recurrence rate wit this surgery can be as high as 40%. (Shah, Int Urogyn, J Pelvic Floor Dysfunction 2008). The scarring and fibrotic tissue that develops from this surgery which utilizes the patient’s own tissue can only restore 50% of the preoperative tissue strength at best.

In general, the cause of the prolapse and incontinence is related to the collagen. Type III collagen is considered much weaker than type I and can run in family members. Stem cell research has been initiated on this area in the DC area and results are pending. As the recurrences rates are so dramatically high, a need for reinforcement was sought out. Ultimately, grafts and mesh as general surgeons use regularly for hernia repairs was discovered to offer an improvement to the significant number of women having to undergo repeat prolapse repairs and incontinence surgeries. It was discovered in clinical trials that reinforcement with grafts significantly decreased the recurrence rates from up to 40 % down to 11% -18% with using mesh types (Davila, Willy, Cleveland Clinic).

Graft options include xenografts (porcine), Allografts (cadaveric) and Autologous types such as fascia lata or rectus fascia which are harvested directly from the patient’s leg and abdomen, respectively, and can increase morbidity associated such as hematoma, hernia, pain levels, longer hospital stays. Non-Autologous Biodegradable type grafts are more unpredictable with life of the graft. Some types were freeze-dried and some retained DNA, had more bacterial adherence and can be more costly.

Consequently, mesh type grafts or slings became the primary choice for managing SUI (stress urinary incontinence). It is presently considered the gold standard over the more invasive Abdominal Burch procedure. An overabundance studies have concluded the success and present, but low risk of the midurethral slings. Once this was known about the success for SUI, many companies to help with the high recurrence rates of bladder prolapse/ Cystocele then introduced the mesh. It is considered a realistic option when patients have anterior or apical prolapse. (No real indication is yet found to use on the posterior compartment for rectoceles.)

The mesh intravaginally acts as a hammock-like support and involves a foreign body reaction. The patient’s host tissue has ingrowth into the polypropylene mesh.

The pros of the mesh graft are that it is completely inert, less expensive, free of microbes, readily available and highly durable.
The disadvantages are the risk of extrusion and exposure out from the vaginal tissue, dyspareunia (pain with intercourse), pelvic pain, and that it was initiated without evidence-based studies. Other complications with mesh grafts or slings include urinary retention, urinary incontinence, voiding dysfunction (frequency/urgency), infection risk, bleeding, bowel and bladder injury, ureteral and nerve injury.

Now there are classifications of mesh complications from the International Continence Society and the International Urogynecology Association. These classsifications relate directly to mesh and prostheses and grafts on female and pelvic surgery.

CTS system: Category Time Site looks specifically at Exposure, perforation, extrusion and contraction to the vaginal vault/ pelvis. Other areas evaluated penetration, dehiscence and if the sinus tract develops. Symptoms as well are assessed in addition to level of infection, which may include abscess or bowel injury.

Incidence of mesh “erosion” is a mean of 10.3%. A meta-analysis reviewed 110 articles with 11,785 patients revealing an overall 0-33% incidence with 0-7% for SUI and up to 21% for POP (Pelvic Organ Prolapse) erosion/extrusion incidents of mesh via a vaginal (not abdominal) approach.

The are no evidence-based studies looking at risk factors such as smoking, immunocompromised patients, age, estrogen deficiency with vaginal tissue atrophy, diabetes, steroids/immunocompromising agents. It was discovered that the commercial kits offered a lower rate of erosion versus a tailored mesh created by the surgeon. (Finamore et al). However, the commercial kits were considered less safe and cost effective than the tailored mesh.

The gold standard surgery for vaginal vault prolapse is the abdominal sacral colpopexy (ASC) which basically suspends the vaginal vault with the use of abdominally placed mesh sutured to a ligament at the anterior side of the upper sacrum. Erosion rate for the ASC is 3.4-5.4% (Brizzolar 2003 and Nygaard, 2004) with up to a 95% success rate. If a concomitant hysterectomy is performed instead of a uterine hysteropexy (tacking up the uterus for uterine preservation), the erosion rate is most commonly known to increase unless a supracervical hysterectomy is performed along with the ASC. Of note, there is no increased risk of erosion when a sling is combined with a POP surgery. There exists a lower incidence in erosion of an open, laparoscopic or robotic approach compared to vaginal approach depending on the depth of the dissection.

If vaginal mesh exposure does occur, typical symptoms include vaginal bleeding, dyspareunia, Hispareunia (male pain with intercourse), abnormal vaginal discharge and vaginal/pelvic pain.
Treatment consists of verifying that there is not urethral or bladder involvement with the extruded mesh, a trial of topical estrogen may or may not be helpful, and finally removal of the exposed portion of mesh. Depending on the degree of symptoms determines whether simple removal or complete removal is necessary. The complete removal is technically more challenging once the mesh causes graft-related pain. Another graft may be necessary to cover a defect following the explantation. Risks can be greater with increased pelvic bleeding, infection such as ischiorectal fossa or pelvic. Typically mesh that is placed vaginally is removed vaginally although much of the deep placements are blinded and consequently the removal will be blinded or at least by careful palpation near pelvic vessels and nerves. Ablation of bleeding vessels and drainage of abscesses may be required. (Urogynecologic Surgical Mesh: Update on the Safety and Effectiveness of Transvaginal Placement for Pelvic Organ Prolapse. July 2012).

Outpatient therapy may include vaginal Trigger point or Pudendal block injections may be helpful as well as cutting the arm to a too tight mesh. Also pelvic floor therapy is an excellent option with high success rates ranging from 50-75% in many cases. Medications such as Valium suppositories, Neurontin and more formalized pain consultations are indicated when pelvic pain is persistent. Pelvic pain with mesh placement may be as high as 52% depending on the mesh type (heavy or light).

If the mesh is extruded into the bladder or urethra, a patient may have painful urination, frequency/urgency, recurrent UTI’s, calculi or fistula, visualized blood in urine (gross hematuria) or pelvic tenderness. These symptoms may occur due to unrecognized bladder or urethral injuries at the time of surgery or high tensioning (which could have been pulled down within the first 7-18 days of surgery) of the sling.

More involved repairs include graft placement, muscle flaps and urethral reconstructions partial bladder removal, multiple procedures, risk of fistula. Redo sling can be performed with another type of mesh sling if in a low risk patient or a biological or autologous graft or sling placement for more high risk patients.

To summarize, with mesh usage comes inherent complications to mesh itself. There are options to mesh use. Each patient case is very individual and requires close examination of the patient’s risk factors and medical history. Specialized trained pelvic surgeons may be more comfortable with mesh placements than less trained or fellowship trained pelvic surgeons. FDA recommends that only specialized trained surgeons place the mesh and inform patients of their training in addition to the risks, complications and alternatives. Decreased use of vaginal mesh for vaginal prolapse has certainly been more mainstream. Identification and ability to address mesh complications can be quite delicate.

References

(Including above listed in parentheses)

Bodell, Dawn, DO, FACOS - special thanks

Jia X. et al. “Efficacy and safety of using mesh or grafts in surgery for anterior and/or posterior vaginal wall prolapse: Systematic review and meta-analysis.” BJOG. 2008 Oct, 115(11): 1350-61.

FDA Safety Communication: UPDATE on Serious Complication Associated with Transvaginal Placement of Surgical Mesh for Pelvic Organ Prolapse. Dept of Health and Human Services. July 13, 2011