Evidence
Alert

Mesh inserted during stoma formation reduces future hernia risk

A mesh inserted when creating a new stoma reduces the chance of a hernia developing around it (parastomal hernia) from about 37% to 16%. Meaning that about five mesh procedures are needed to prevent one hernia appearing within the first five years.

A stoma is an opening of part of the intestine onto the skin, allowing waste products to leave the body. Parastomal hernias, that appear beside the stoma, are a common complication. They can be painful and prevent the stoma from working properly.

The 10 trials in this review used different mesh types and positions, making it harder to compare findings. They mainly included people who were overweight so the findings may not automatically apply to people at lower risk.

Existing research has given rise to mixed opinion over the value of a prophylactic mesh and hence there is wide variation in practice. This review supports the use of a mesh but highlights the need for further investigation into the best technique and type.

Why was this study needed?

About one in every 500 people in the UK is living with a stoma. Ileostomies and colostomies are created to divert intestinal contents for many conditions including inflammatory bowel disease, cancer and inherited bowel conditions.

A parastomal hernia occurs when part of the intestine bulges out under or around the stoma. This is due to the weakness in the abdominal muscles from the creation of the stoma. It is a common complication, thought to occur in up to half of people with stomas, depending on the type of stoma. They can cause discomfort, difficulties fitting stoma devices, stoma dysfunction including obstruction and may need surgical repair.

Even with surgical repair, hernia recurrence rates are more than 30%. One technique to prevent hernias at the outset involves reinforcing the stoma with a biological or prosthetic mesh, designed to strengthen the abdominal wall. However, surgeons have questioned how robust existing studies are and so the uptake of this procedure is varied.

What did this study do?

This systematic review and meta-analysis pooled the results of ten randomised controlled trials. They compared the rate of parastomal hernia in 324 people having mesh insertion at the time of stoma formation with 325 people with no mesh insertion. They also looked at rates of infection. Follow up ranged from one to five years.

This was a high quality review but results should be interpreted with care because some included trials had a high risk of bias. There was also wide variation between the trials in terms of different types of mesh and surgical techniques. The trial participants weren’t representative of the whole ostomy population as most were men having a colostomy for colorectal cancer. Finally, the results don’t include how the mesh might impact on patient reported outcomes like comfort.

What did it find?

  • Overall, parastomal hernias occurred in 16.4% of people in the mesh group (53/324) compared to 36.6% in the no-mesh group (119/325), (odds ratio [OR] 0.24 (95% confidence interval [CI] 0.12 to 0.50).
  • A number needed to treat analysis suggests it would take five people receiving mesh procedures to prevent one hernia occurrence (95% CI 3.7 to 7.3).
  • There were a low number of hernia repairs; 2.5% in the mesh group and 8.9% in the no mesh group.
  • There was a very low rate of infection around the stoma, at 2.2% in the mesh group compared to 3.4% in the no mesh group.
  • There seemed to be no effect on hernia rates according to the type of mesh or where it was placed. The risk of bias of the studies also did not seem to affect the outcome. However, there should be less confidence in these results as there are only ten studies and all are quite different to each other.

What does current guidance say on this issue?

There is no relevant guidance available on prevention of parastomal hernias in the UK.

The American Society of Colon and Rectal Surgeons advises that lightweight polypropylene mesh be placed at the time of permanent stoma creation to decrease parastomal hernia rates.

What are the implications?

With no UK guidance on the use of mesh there is wide variation in practice. This high quality review suggests that surgeons might wish to consider mesh placement when creating stomas. There had been concerns that mesh may increase the risk of infection but this was not shown in this review. It could improve quality of life, though more research into mesh tolerability from patients would be useful.

Commissioners would need to consider the small increase in operating time needed for mesh insertion against the reduced need for repeat surgery. The best choice of mesh placement technique, mesh position and mesh material remains unclear.

 

Citation and Funding

Cross AJ, Buchwald PL, Frizelle FA, Eglinton TW. Meta-analysis of prophylactic mesh to prevent parastomal hernia. Br J Surg. 2017;104(3):179-86.

No funding information was provided for this study.

 

Bibliography

Carne PW, Robertson GM, Frizelle FA. Parastomal hernia. British Journal of Surgery 2003;90(7):784-93.

Cheung MT, Chia NH, Chiu WY. Surgical treatment of parastomal hernia complicating sigmoid colostomies. Dise Colon Rectum. 2001;44(2):266-70.

Hendren S, Hammond K, Glasgow S, et al. Clinical Practice Guidelines for Ostomy Surgery. Clinical Practice Guidelines Committee of the American society of Colon and Rectal Surgeons. Illinois; 2015.

NHS Choices. Colostomy. London: Department of Health; 2015.

NHS Choices. Ileostomy. London Department of Health; 2016.

Rees M, Jones H, Cragg J, et al. Prosthetic mesh placement for the prevention of parastomal herniation. Cochrane Database Syst Rev. 2013;(12):CD008905.

The Colostomy Association. Parastomal Hernias. The Colostomy Association. London; 2015.

The Colostomy Association. What is a stoma? The Colostomy Association. London; 2015.

Shabbir J, Britton DC. Stoma complications: a literature overview. Colorectal Disease 2010;12(10):958-64.

Sugarbaker P. Prosthetic Mesh Repair. Paraostomy Hernias: Prosthetic Mesh Repair. Office Journal of the American Society of Abdominal Surgeons. 2014.

Tekkis PP, Kocher HM, Payne JG. Parastomal hernia repair: modified thorlakson technique, reinforced by polypropylene mesh. Dis Colon Rectum. 1999;42(11):1505-8.

Produced by the University of Southampton and Bazian on behalf of NIHR through the NIHR Dissemination Centre

Commentaries

Expert commentary

The achilles heel of stoma formation is the development of a parastomal hernia. Whilst lots of techniques have been used to try and reduce the risk, the reported incidence remains high.

Surgeons have been concerned over the use of an implant (mesh) around a stoma because of the risk of mesh related complications, most notably infection and mesh erosion into the bowel.

This meta-analysis of randomised controlled trials has revealed more than a 50% reduction in the risk of parastomal hernia formation with the use of mesh without an increase in mesh related complications. The randomised controlled trails included had quite significant heterogeneity in terms of surgical technique and follow up, however the meta-analysis provides a compelling argument that prophylactic mesh placement has an important role.

Mr David Sanders, Consultant Surgeon, North Devon District Hospital; Board Member, British Hernia Society