Parastomal Hernia – Latest Knowledge and Approach

Abstract

Parastomal hernia is developed after the creation of a stoma which happens after bowel resection or diversion. With the developed screening program for bowel cancer and its related surgeries, a lot of stomas have been done and its complications including parastomal hernias appeared. At the same time, its diagnosis is well developed with the advancement of imaging techniques, but unfortunately, there is no standard treatment for the repair. It is noticed that each surgeon deals with the PSH with their own experience as there is no strong evidence or standard approach, with most of the PSH patients treated conservatively till they reach a big size or develop other complications. A lot of effort was spent on the primary prevention of PSH and still under trial. Considering evidence-based medicine, the best way to deal with PSH is to be tailored to the patient’s extent of complaint, which is determined by the surgeon’s experience. It is estimated that third of these patients are treated surgically, and this is due to the high recurrence rate that makes surgeons try to avoid surgical correction. In this chapter, we will try to cover the latest update about the diagnosis, complications and repair techniques.

1. Introduction

Parastomal hernia is a form of incisional hernia because it happens in a surgical incision and is considered one of the most complications that happen after stoma formation [1]. In this complication, part of the intraabdominal viscera protrudes through the same opening of the stoma surrounded by a hernia sac [2].

Earlier in 1973 Devlin put a classification based on four types of hernia [3]:

type I—integumentary (the so-called true parastomal hernia); type II—subcutaneous; type III—intra-stomal; and type IV—pseudo-pre-stomal.

From this classification, we notice that not all parastomal deformities are PSH and this makes it difficult in treating different abnormalities and made this classification weak and difficult to implement [4].

As a result, two more classifications had been proposed with the aid of the CT scan by Moreno-Matias in 2009 [5] and Seo in 2011 [6] and another one by Szczepkowski in 2011 based on clinical examination of the hernia [6, 7].

None of these classifications had been used in clinical trials so they lack the evidence and because only Szczepkowski considered the presence of an incisional hernia which is needed for the repair together with the PSH but requires more accurate measure than the clinical examination which can be achieved by the CT scan; for this reason, the European Hernia Society (EHS) in 2014 had published a new classification based on Szczepkowski classification to be the standard for evidence-based therapeutic guidelines (Table 1). The European Hernia Society Subclasses of classification were defined as follows:

• type I—PSH is less than 5 cm in diameter without coexisting incisional hernia.

• type II—PSH is less than 5 cm in diameter with coexisting incisional hernia.

• type III—PSH is larger than 5 cm in diameter without coexisting incisional hernia.

• type IV—PSH is larger than 5 cm in diameter with coexisting incisional hernia.

Moreno-Matias in 2009 and Seo in 2011	Szczepkowski 2011
0—CT image normal, peritoneum follows the wall of the bowel forming the stoma, with no formation of a sac	I—isolated, small parastomal hernia
Ia—bowel forming the colostomy with a sac of under 5 cm	II—small parastomal hernia with coexisting midline incisional hernia without any significant front abdominal wall deformity
Ib—bowel forming the colostomy with a sac of over 5 cm	III—isolated, large parastomal hernia with front abdominal wall deformity
II—sac containing omentum	IV—large parastomal hernia with coexisting midline incisional hernia, with front abdominal wall deformity
III—sac containing an intestinal loop other than the bowel forming the stoma

Table 1.

Moreno-Matias and Seo vs. Szczepkowski classification.

The coexisting incisional hernia is in the previous scar.

Additionally, in each type of PSH one should note whether it is primary (labelled P) or recurrent (labelled R), This classification should be aided with a CT scan to help for accurate measurement of the defect [8].

2. Epidemiology

PSHs usually develop in the first year after its creation; however, the incidence increases in the following years up to twenty years. It has been noticed that in colostomy the incidence in the first year is 30%, becoming 40% in two years and 50% in three years to reach 76% in twenty years [9, 10].

The hernia development is influenced by the ageing process of the muscles with increasing risk each year by 4% [Odds ratio—1.04; p = 0.4] [11].

Global data shows that the incidence of PSH is related to the specific type of stomas is as follows:

• end colostomy—4.0–48.1% (mean: 15.3%),

• loop colostomy—0.0–30.8% (mean: 4.0%),

• end ileostomy—1.8–28.3% (mean: 6.7%),

• loop ileostomy—0.0–6.2% (mean: 1.3%) [11, 12, 13].

The risk factors for developing PSH are as follows:

1. Age: Above 60 years. The most important factor is statistically significant.

2. Obesity (BMI > 30 kg/m²).

3. Waist size (>10 cm).

4. ASA classification (>2).

5. Smoking.

6. Diabetes mellitus.

7. Physical labour.

8. Chronic cough.

9. COPD (chronic obstructive pulmonary disease).

10. Immune disorders.

11. Steroid therapy.

12. Cancer.

13. Ischaemia.

14. Crohn’s disease.

15. Disorders involving collagen metabolism.

All these apart from age are non-statistically significantly linked to PSH [14, 15, 16, 17].

The site of the stoma was claimed to be a risk factor for the development of PSH but there is a meta-analysis of 24 publications shows that the incidence of PSH is not affected by the relation to the rectus abdominis muscle; for example, the percentage of stomas formed through the rectus abdominis muscle versus adjacent to the muscle is as follows: 3% vs. 22% [18], 37% vs. 33% [19], 52% vs. 46% [20].

Another problem that most of surgeons are worried about is the high recurrence rate after corrective surgery, and it can be summarised as follows:

• after surgery with stoma transposition—0–76.2% (mean: 24.3%),

• after mesh plasty—0–33.3% (mean: 2.9%),

• simple tissue plasty—46–100% (mean: 64.9%) [17]

After corrective surgery, the risk of recurrence is [21]:

radiological recurrence (p = 0.05):

• with mesh—22%,

• without mesh—45%;

clinical recurrence (p < 0.001):

• with mesh—13%,

• without mesh—80%

As PSH is associated with a high incidence of development, there are certain measures that can be implemented to reduce the risk, these include [22, 23]:

• Good preoperative assessment.

• Identification of the risks that had been mentioned above.

• Checking for any collagen metabolism disorders.

• Weight reduction programme.

• Stop smoking for at least 2 months prior to elective procedures.

• Encourage physical activities.

• Counselling with the stoma nurse and marking the area that is suitable for the patient.

3. Clinical presentation

The most common presentation for PSH is a deformity, lack of symmetry and bulging of the abdominal wall especially on straining. However, the main bothering symptoms are discomfort and poor fitting of the stoma appliance that makes it leak especially at night [22, 23].

Another important complaint is the psychological problem as the patient starts to have accidents and is afraid of ongoing enlargement of the hernia [23].

As with other hernias, acute complications like strangulation or obstruction can be encountered but are rare, and it usually started with obstruction and then develops into strangulation, which is difficult to diagnose and treat [1].

4. Diagnosis and indications of interventions

In most patients, clinical examination is enough to establish the diagnosis, although some hernias are easily missed because of obesity and tenderness to palpate. In these situations and in order to get a clear classification, a CT scan or ultrasound is needed [24].

Most of the surgeons adopt watchful waiting because of the high risk of recurrence making the surgical intervention limited to those with severe symptoms or complications that happen in 30% of the patients.

The indications for surgery can be divided into absolute and relative.

Absolute indications (acute complications)

• obstruction, when a patient develops intestinal obstruction due to an obstructed loop of the bowel within the hernia.

• Strangulation, when a segment of viscera within the hernia develops ischaemia due to a cut of the blood supply.

• Incarceration, which is the irreducibility of the hernia.

• Parastomal fistula,

• Perforation, when perforation of the bowel happens within the hernia sac.

• Stomal ischaemia.

Of course, a full assessment of the patient’s condition needs to be done as sometimes the decision of palliation in severe frailty is made and sometimes repair of local complications such as obstruction and perforation is done within the hernia sac without repair of the hernia especially in a comorbid patient with loss of domain.

Relative indications:

• Recurrent admission with incarceration.

• Recurrent temporary obstruction, treated conservatively in the past.

• Difficulty in caring for the stoma bag, with recurrent leaks.

• Problems with irrigation in patients with constipation.

• Painful hernia.

• Pressure-related erosion or erosion of the adjacent skin.

• Social or aesthetic unacceptance.

• Irreducibility of the hernia.

• Other associated complications that need fixing, like stenosis or prolapsed.

However, it is absolutely contraindicated to repair the PSH in end-stage cancer and relatively in unresectable malignant tumours and severe comorbidity.

5. Management

5.1 Watch and wait

The widest approach adopted by most surgeons as we see only a third of the PSH is repaired, the reasons behind that are that the patients are asymptomatic, fail to report their problems, are afraid of recurrence or have other comorbidities that make the repair risky [11].

The EHS (European Hernia Society) Guidelines published in 2018 considered the watch and wait policy has no specific recommendations as it lacks evidence. In an asymptomatic hernia patient with no risk of strangulation, a watch-and-wait policy with regular monitoring is recommended [25].

5.2 Surgical repair

5.2.1 Indications of surgical intervention

It can be divided into two categories:

1. Emergency repair.

   1. Strangulation.

   2. Obstruction.

   3. Incarceration.

   4. Ischaemia of the stoma.

2. Elective repair:

   1. Previous complications had been successfully treated with conservative measures like obstruction or incarceration.

   2. Parastomal fistula.

   3. Difficulty to take care of the stoma including placing the collecting bag.

   4. Difficult irrigation.

   5. Pain and difficulty in wearing the clothes.

   6. Skin erosion.

   7. Prolapse.

   8. Patient preference.

It is worth knowing that it is contraindicated to repair the PSH in terminal malignant conditions, metastatic cancer, and serious comorbidities [13, 16].

5.2.2 Before surgery

• A computerised tomography scan (CT scan) is needed to plan the type of surgery.

• It is better to have a period of three months after the last abdominal surgery.

Smoking should be stopped at least 4 weeks before the operation.

• Weight reduction for high BMI >30.

• Full anaesthetic assessment including CPET is needed.

• Antibiotics are needed before the operation.

• VTE prophylaxis.

These points are general for all abdominal wall hernias including PSH [26, 27].

6. Surgical options

There are different approaches for PSH repair, and the choice of each technique depends on the surgeon’s experience and the patient’s condition.

6.1 Suture repair

This is the oldest technique that had been described in 1965 by Thorlakson. It is used mainly in emergency repair when other techniques are not suitable and sometimes as a step for other definitive procedures.

It has a high failure rate with recurrence ranging from 45 to 100%.

It is done by an incision around the stoma by about 5 cm, dissection of the sac and suturing the defect under tension.

6.2 Relocation

Simple relocation of the stoma is not a wise option for different reasons: It needs a midline laparotomy wound which carries its own complications such as incisional hernia and wound dehiscence, the old stoma wound may develop a hernia (52%) and the new stoma may develop a new parastomal hernia [13, 28].

Current practice by most surgeon that they choose relocation for the stomas that had been placed wrongly and they use a non-absorbable mesh primarily in the new stoma site to reduce the recurrence [29, 30].

The relocation of the stoma should be avoided unless the fascia adjacent to the original site is really week and cannot hold it [31].

6.3 Mesh repair

6.3.1 Open mesh repair

Onlay mesh repair is achieved with a semicircular incision on the lateral edge of the stoma and then, the mesh can be placed in a keyhole technique or stove pipe hat technique when the stoma is passed through the opening of the mesh and another mesh is then attached to the bowel circumference on the onlay mesh [32].

The recurrence rate is 25.9% at 48 months, with 1.9% infection of the wound and 2.6% mesh infection.

Retro muscular mesh repair is by placing the mesh beneath the rectus abdominis muscle using the Sugarbaker technique, keyhole, or midline incision. The associated incisional hernia can be repaired with mesh, or the stoma can be relocated [33].

These several techniques have an average pooled recurrence rate of 6.9%, while the incidence rate of wound infection is 4.8% in the absence of mesh infection.

Intraperitoneal placement of the mesh makes it less prone to infection [33].

A systematic review in 2014 concluded no sufficient evidence about which mesh repair is more successful, but the overall recurrence rate is 7.9–14% compared to suture repair which is 57% [34]. The lowest recurrence rate is for neuromuscular repair at 6.9%, while the Sugarbaker technique is 11.6% and the onlay mesh is 17.2%. The worst is the intraperitoneal keyhole with 34.6% [35].

In conclusion, if contamination happens, the biological mesh is the best option but has a high recurrence rate. While using medium weight or lightweight, large-pore polypropylene placed in the retro-muscular fashion is acceptable regarding infection and recurrence for PSH repair where there is a risk of contamination [34, 35].

6.3.2 Laparoscopic repair

Similar to the open repairs that had been mentioned above, laparoscopic techniques had been applied like retro muscular mesh placement or intraperitoneal mesh placement (Lap IPOM), performed using any of the keyhole, Sugarbaker, or sandwich approaches.

Compared to the open technique, the laparoscopic approach has less morbidity by 60% [36].

Regarding the recurrence rate, it is found that the recurrence is less in laparoscopic repair with no increase in wound infection rate, which is at 3.3%, mesh infection at 2.7% and morbidity at 17.2% [37].

In 2018, the EHS indicates no preference for laparoscopic or open repair with mesh for elective surgery [25].

6.3.3 Laparoscopic intraperitoneal only mesh: Keyhole technique

This was done first by Hanson as a keyhole approach. The abdomen is entered through the contralateral side of the stoma with the working port away from the stoma, and adhesiolysis is performed clearing 5 cm away from the defects in the abdominal wall.

One piece of the bilayer is cut in the centre forming a slit that results in a hole of 2 cm which houses the stoma in the middle, and the rest of the mesh is used to make a keyhole shape by wrapping it on the stoma, and then fixed in position using sutures or tacks [38].

The keyhole technique is suitable when the mesentery length is inadequate [39].

6.3.4 Laparoscopic intraperitoneal only mesh: Modified Sugarbaker technique

This was done first by Votik when he combined laparoscopic and Sugarbaker techniques.

In this technique, the non-slit bilayer or coated-non-absorbable meshes are used to cover the stoma and the hernia [40].

The hernia was reduced first; then, the defect is covered with the mesh centred over the site of the stoma, and the mesh was then extended to 5 cm or more. It is optimum for the lateralized colon up to the abdominal wall to form a tunnel of not less than 5 cm for the bowel before entering the enterocutaneous junction. Then, the mesh is fixed with tacks or sutures [41].

For this method, the rate of recurrence was found to be 10.2%compared to the keyhole of 27.9% [42].

This method is recommended and optimum if the mesentery has a good length [39].

6.3.5 Laparoscopic intraperitoneal only mesh: Sandwich or two-patch technique

The sandwich technique was made by LeBlanc and Bellanger when two meshes used one to cover the opening of the stoma and the second mesh patch in the opposite direction to the first mesh patch; for this, DualMesh Plus TM was employed and positioning the slit is used to cover the defect which has been created in the previous mesh.

Berger et al. [43] create a modification in this technique by combining the Sugarbaker and the keyhole method and employing a pair of mesh pieces. The first mesh is 15 × 15 cm, which is positioned using a keyhole technique with a central hole of 1.5 cm in size, and this mesh is placed around the stoma to wrap it and cover the defect in the same time and then closing the incised mesh using spiral tacks and two transracial sutures, and fixing the mesh at the same time with the tacks to make it secure in its place. Another non-absorbable mesh is used to cover the first mesh and the whole anterior abdominal wall. The stoma loop is then positioned between the two meshes with lateralization of more than 5 cm. Fixing is with spiral tacks and transracial sutures [43].

6.3.6 Laparoscopic transversus abdominis release (TAR) and modified retro rectus Sugarbaker

In this technique, component separation is through the TAR to create a retro rectus space and positioning of the mesh in this space without touching the intestine. Paulie et al. [44] first describe open TAR in combination with Sugarbaker technique [4].

The mesh is usually placed in the retro rectus space in a manner that is similar to the Sugarbaker technique and laterally in a sling around the bowel, medially it extends to the contralateral Linea semilunaris, so can strengthen the Medline.

The advantage of this technique is that there is no need to take down the mesh and lower wound problems, skin necrosis and subcutaneous seroma if compared with the ant component separation. Also, it is a cost-effective method as we can use by using non-coated non-absorbable mesh and allow integration of the mesh on both sides, one side with the anterior abdominal wall and the other side with the post-facial layers. This provides superior tensile strength [43, 44].

7. What type of mesh to use

As the parastomal hernia has a high rate of recurrence and failure, there were a lot of controversies about the type of mesh and its effect on recurrence and other post-operative morbidities especially the presence of mesh making the operation a clean contaminated not like strictly clean operations.

A post hoc analysis of a multicentre randomised controlled trial done in the United States comparing biologic versus synthetic mesh in a contaminated ventral hernia concluded that there is no difference in wound morbidity, reoperation, two-year hernia recurrence rate and the quality of life in PSH repair, so the cost should be taken in consideration in operation [45].

8. Which technique is the best for the outcome and long-term follow-up?

Although we mentioned earlier that the best technique is the technique that the surgeon is confident to do, still continuously improving the techniques is needed in PSH hernia repair given the high morbidity and failure rate.

A retrospective cohort study done in Finland across five university hospitals and 4 central hospitals: it showed that the recurrence rate is as follows:

• Keyhole 35.1%

• Sugarbaker 21.5%

• Sandwich method 13.5%

• Specific funnel-type mesh 15%

• Other techniques 26.3%

From this, we find that the recurrence is high in all types of repair of PSH and this is the cause that PSH repair is low in volume [45].

9. Prevention

Once a stoma is created, there will be a risk of the development of PSH and prevention of its development is better than repair.

The reduction of the risk can be achieved by good patient preparation, patient education with the stoma nurse, prior marking of the stoma and treating the modifiable risk factors like smoking and obesity and encouraging exercise.

During the technique, it is advised to use a small trephine less than 3 cm as it is associated with a higher risk of development of PSH [4]. Although it still lacks solid evidence.

There is growing evidence about prophylactic mesh use during the creation of the stoma to prevent recurrence. A study comprised an analysis of 12 systematic reviews and meta-analyses, including the Cochrane review, for a period covering 2010–2018. The analysed studies included 451–844 participants. The study found that the rate of PSH is reduced when a prophylactic mesh is used compared to the standard stoma formation.

Now, the EHS strongly recommends the use of prophylactic mesh for PSH prevention. However, because of poor evidence, it is now advised to use prophylactic mesh for a cancer patient when planned end permanent colostomy and this needs to be discussed with the patient.

The post-operative instructions to reduce the recurrence after the repair are generally similar to other ventral hernia repairs which include: avoidance of heavyweight lifting for three weeks, use of abdominal binder for three to six months and after that the binder used during heavy exercise [39].

10. Conclusions

PSH is a common complication after stoma surgery and its incidence rises with time after surgery. Numerous approaches are adopted by surgeons ranging from the watch and waiting to extensive big surgery. Only a third of the patients with PSH are treated surgically with a significant recurrence rate which made the surgeons try to find different techniques to reduce the risk of recurrence. The most popular now is intraperitoneal onlay fashion using the Sugarbaker technique as it has a favourable outcome. Moreover, the two-pouch mesh repair is gaining popularity. In elective cancer patients when an end stoma is adopted, it is recommended now to use a prophylactic mesh. Further studies are ongoing now to determine the best technique with regard to the recurrence and other complications.

Conflict of interest

The author has no conflict of interest.

Thanks

For My parents who always pray for my success.

For My wife and children: Alyaa the most supportive and loving person and Ola, Sama and the little Misk, who give the joy of life.