Complex Abdominal Wall Reconstruction and Parastomal Hernia Repair after Colorectal Surgery

Charlotte Horne

Ajita Prabhu

GENERAL PERIOPERATIVE CONSIDERATIONS

Patient Assessment

Indications for parastomal hernia repair include obstructive symptoms, persistent uncontrolled pain, and difficulty with pouching.
- The first two indications obviously necessitate repair.
- Issues with ostomy appliances are not trivial and can have significant lifestyle limiting and financial consequences due to patient concerns for accidental leakage as well as the cost of frequently changing ostomy supplies. Even if asymptomatic otherwise, we will offer repair.
- This approach was studied by Kroese et al., and although 21% of patients in the watchful waiting group required surgical intervention, there was no difference in rates of emergency surgery as well as postoperative morbidity in those who crossed over to the surgical therapy group.
- As recurrence rates of a parastomal hernia after repair approach 20%, employing a nonoperative approach is reasonable and has not been shown to be associated with increased morbidity. These patients should be adequately counseled about symptoms of incarceration.

Initial assessment of a patient deemed to require a parastomal hernia repair always includes evaluating the patient for possible ostomy reversal.
- Presence of concomitant midline hernias, multiply reoperative abdomens, or other factors that may have been previously limiting to reversal may no longer be absolute or relative contraindications to reversal, and a reversal should always be performed when possible.
The next step in preoperative evaluation is to assess medical comorbidities, such as the presence of malignancy, need for ongoing chemotherapy or radiation, overall life expectancy, weight, smoking status, and other significant medical comorbidities.
- Recurrence after parastomal hernia repair in morbidly obese patients is associated not only with an increase in recurrence but also with postoperative morbidity.
- All patients are counseled about the importance of smoking cessation, and cessation is verified with urine nicotine testing.
- Uncontrolled diabetes is well known to increase the risk of wound morbidity.
  - Preoperative evaluation in diabetic patients includes routine assessment of HbA_1c.
  - Glycemic optimization, even 60 days prior to surgical intervention, has been shown to decrease postoperative morbidity.
  - Our goal HgbA_1c prior to scheduling parastomal hernia repair is <8 as this has been shown to be associated with a significant decrease in postoperative surgical site infection.
- For patients with inflammatory bowel disease, optimal surgical results are achieved by ensuring disease is adequately controlled.
  - If biologic agents are necessary to achieve disease control/remission, these medications are continued.
  - These patients may also require the use of steroids to achieve disease control/remission. When possible, patients should be maintained on the lowest steroid dose required.

Operative Approach

Table 45-1 Proposed algorithm for preoperative planning of parastomal hernia repair.

There are many different approaches to the repair of parastomal hernias, including primary repairs, stoma relocation as well as both laparoscopic and open techniques.
- Patient factors, previous operations, type of stoma, and other concomitant hernias dictate appropriate operative approach.
- Although primary suture repair is associated with minimal operative morbidity, recurrence rates approach 69% postoperatively.

Common laparoscopic approaches include the keyhole repair and the Sugarbaker repair. These approaches involve the intraperitoneal placement of mesh.
- In general, the laparoscopic approach is associated with decreased surgical site infection.
- Analysis of these techniques shows a lower recurrence rate with the Sugarbaker repair.
  - In our practice, patients without prior parastomal hernia repairs, absence of associated midline hernia, and smaller hernia defects and those who do not have multiply reoperative abdomens are the ideal candidates for a laparoscopic approach.
Numerous techniques have been illustrated for the open repair of a parastomal hernia.
- Here we present approaches based on reinforcement of the defect with mesh, as we consider this to be standard of care for elective cases.
- The mesh may be placed in an onlay manner around the stoma in the prefascial plane; it may be placed posterior to the rectus abdominis muscle in the retrorectus or preperitoneal plane, or it can be placed intraperitoneally in an underlay manner.
- The onlay technique is beneficial as it does not require a laparotomy; however, recurrence rates with this technique are the highest at ˜15%.
- Both the retrorectus and preperitoneal repair require a laparotomy for appropriate hernia reduction and mesh placement.
  - These techniques are associated with an overall low recurrence rate, 7% and 9%, respectively, and low postoperative wound morbidity of ˜2%-4%.
  - Our preferred technique for open parastomal hernia involves stoma takedown and relocation on the contralateral side of the abdomen when possible with placement of mesh in the retrorectus plane.
  - Placement of mesh in the retrorectus plane avoids complications associated with intraperitoneal mesh, including extensive adhesions and erosion.
- Re-siting the stoma is ideal as it moves the ostomy to a location of healthy abdominal wall, allowing for reinforcement of the old fascial defect as well as the new fascial defect. Still, this approach is associated with a recurrence rate as high as 11% in the first 13 months of repair, which serves to highlight the challenging nature of parastomal hernia repair in general.

Patient Preparation

Patient optimization prior to undergoing parastomal hernia repair is critical as these operations can be lengthy due to extensive intra-abdominal adhesions, previous mesh placements, and stoma management.
Prior to undergoing repair, all patients undergo cross-sectional imaging (usually a computed tomography) prior to repair as the presence of concomitant hernias will determine operative approach. We routinely obtain all operative reports from prior operations when possible.
Patients are evaluated by a certified stoma nurse for preoperative stoma marking. Preoperative site marking allows the patient to be evaluated in both the sitting and standing positions, and significant skin creases can be assessed to ensure the new ostomy is in the most optimal location.
In our practice, we routinely relocate the stoma if possible, during an open parastomal hernia repair; therefore, identification of an appropriate site preoperatively provides the patient with an easily manageable stoma postoperatively.
We do not routinely have patients perform a bowel prep prior to surgery, as we have found that patients undergoing hernia repair in a contaminated setting with bowel prep have a higher incidence of surgical site infection requiring procedural intervention.

Mesh Choice

Appropriate mesh choice is often dictated by whether laparoscopic or open approach will be utilized.
When parastomal hernias are repaired laparoscopically either an expanded polytetrafluoroethylene (ePTFE) mesh or a barrier-coated lightweight polypropylene mesh is utilized.
- We routinely use barrier coating mesh—it prevents tissue ingrowth on the peritoneal surface, reducing adhesions forming to the bowel.

In an open approach, both biologic and synthetic mesh have been used.
- Although there have been concerns about synthetic mesh in the proximity of the stoma and increased risk of wound morbidity in contaminated hernia cases, multiple studies have shown that a medium weight polypropylene mesh is both safe and effective in parastomal hernia repair.

Laparoscopic Parastomal Hernia Repair

Laparoscopic parastomal hernia repair is an attractive option for parastomal hernias and has been shown to have decreased postoperative pain as well as a decreased incidence of postoperative wound and mesh infection (3.8%) and recurrence (17.4%).
The keyhole technique and the Sugarbaker technique are the most commonly used approaches.
- A laparoscopic Sugarbaker approach has been shown to have the lowest postoperative recurrence rate of 10.2%; however, complications with mesh erosion into the ostomy can be devastating.
- As the Sugarbaker approach requires a significant amount of bowel length to be mobilized, patients with ileal conduits or transverse colostomies may not be candidates for this approach due to the location of the ureters or a shortened mesentery.
- The keyhole technique has been shown to have a moderately higher recurrence rate of 27.9%, likely due to the contraction of the ePTFE mesh reinforcement that enlarges the slit over time.
- In both techniques, the stoma is left in situ.
- Laparoscopic stoma relocation is not currently routinely done.
Candidates for a laparoscopic approach include those without concomitant midline defects, no previous history of prior parastomal hernia repair, and those with smaller parastomal hernia defects.
Cross-sectional imaging is routinely performed in patients thought to be appropriate candidates for a laparoscopic approach to evaluate for other hernia defects and any other intra-abdominal pathology.

Laparoscopic Technique

Positioning

In both the keyhole and Sugarbaker techniques, patients are placed supine.
Arms are tucked to facilitate laparoscopic dissection as often the surgeon and the assistant stand on the same side of the operative table.
All patients received appropriate antibiotic prophylaxis, and prophylactic heparin is administered prior to incision.
The stoma is oversewn from skin to skin using a 0 permanent braided suture.
A gauze and sterile dressing are then placed over the stoma to prevent spillage of enteric contents and minimize contamination during the procedure.
The patient can be placed in mild Trendelenburg and rotated so the side with the ostomy side mildly elevated to allow for better visualization.

Port Placement

Appropriate port placement is essential to facilitate adhesiolysis and mesh placement.
As patients may have significant abdominal wall adhesions, and to facilitate mesh placement, ports should be placed as lateral as possible.
We routinely place a total of three ports, two 5-mm and one 12-mm port, with an additional port added, if necessary, to facilitate retraction and mesh fixation (Fig. 45-1).

FIGURE 45-1 ▪ Port placement: Ports are placed on the contralateral side of the abdomen to the ostomy when feasible. We routinely use a 12-mm port and two 5-mm ports. (From Appearance of an ostomy. (n.d.). Retrieved June 10, 2018, from https://www.fascrs.org/patients/disease-condition/ostomy-0.)

Adhesiolysis

Access is gained in the abdominal quadrant furthest away from the stoma when possible. Our preference is to gain access to the abdomen via an open cut-down approach; however, other methods of entry can be effective.
Overall, choice of abdominal entry technique is at the discretion of the operating surgeon, being cognizant of a high likelihood of intra-abdominal adhesions.
Subsequent ports are placed on the contralateral side of the abdomen to the ostomy.
- If access cannot be gained in the abdomen contralateral to the ostomy, we routinely place the initial port as far from the stoma as possible to facilitate adhesiolysis.
Initial dissection begins with adhesiolysis performed sharply to prevent inadvertent thermal injuries to the bowel; however, energy devices can be utilized to facilitate hemostasis.
Adhesiolysis is performed to completely clear the abdominal wall circumferentially around the hernia defect for mesh placement.
- Adhesiolysis is deemed complete when there is adequate space to place an appropriately sized piece of mesh.