Surgeons provide insight into the latest material choices and technique approaches for ventral and inguinal hernia repair, as well as what to expect for the future as this area of surgery continues to advance.
For most general surgeons practicing today, hernia repairs are a common procedure. As with any area of surgery, approaches to hernia repair are constantly evolving and advancing. Surgeons are faced with a multitude of materials from which to choose, including synthetic meshes and biologic grafts. In terms of technique, minimally invasive approaches are becoming increasingly common, but open surgery is a mainstay in certain hernia types and cases. To ensure a successful repair, surgeons must be informed of the latest techniques, trends and approaches.
Recently, Surgical Products spoke with William Cobb, MD, co-director of the Hernia Center at the Greenville Hospital System University Medical Center in Greenville, SC about topics related to ventral hernia repair. Meanwhile, David Siegel, DO, FACOS, General Surgery Program Director at St. John Macomb-Oakland Hospital in Madison Heights, MI provided a perspective on topics related to open inguinal hernia repair. Together, they offer insight into the material choices and technique approaches to ventral and inguinal hernia repairs, and what surgeons can expect for the future in this area of surgery.
Open Or MIS?
Surgical Products: As minimally invasive surgery becomes increasingly common, how has it affected hernia repair?
Dr. Cobb: From a ventral hernia standpoint, I think the feeling among most is that the laparoscopic approach is the preferred technique. Certainly, the biggest benefit of the laparoscopic approach for ventral hernia repair is the reduction in wound and mesh complications. Through the years, the technique has advanced, but the basic principles have remained the same. Surgeons have gotten better at taking the adhesions down, which is somewhat of the “Achilles Heel” of the operation. Some have adapted or modified the type of mesh and the technique of introducing it into the abdomen. The overlap of mesh needed has increased in a laparoscopic ventral hernia repair—initially it was 3 cm, now we know it’s more like 5 cm. However, what remains the same is the improvement in wound and more importantly, mesh complications, with the laparoscopic technique.
Dr. Siegel: Laparoscopy has been done for years, and through those years we have tried different hernia repairs laparoscopically. However, some surgeons still perform inguinal hernia repairs primarily open because with laparoscopy, there is a risk with giving a bigger anesthetic to the patient. Further, experienced surgeons have achieved a recurrence rate in open inguinal hernia repairs of only about 1 to 2 percent.
The thought in doing laparoscopic hernia repair is that patients experience less pain and have a quicker recovery period. Some patients don’t necessarily have that much less pain and they don’t have that much quicker of a recovery. We don’t want to expose them to a higher recurrence rate and higher risk if we’re not getting the benefit of less pain and quicker recovery.
For open inguinal hernia repair, there are really two approaches. The anterior approach includes the Lichtenstein repair, which is probably the most common repair done in the United States, as well as the Shouldice repair. Then, there is the preperitoneal approach, which started with the Stoppa repairs. There are numerous types of other preperitoneal repairs that are done. The recurrence rate has always been slightly higher in the preperitoneal approach and that’s probably why the anterior approach is done more commonly.
Surgical Products: How does a surgeon decide which cases are best suited for laparoscopic technique, and which should be performed open?
Dr. Cobb: If you have someone who has significant heart or lung comorbidities that prohibits general anesthesia, they are not a candidate for laparoscopy. Patients must tolerate general anesthesia for laparoscopic hernia repair. Other contraindications to fix a ventral hernia laparoscopically include:
Patients who have poor skin quality. These patients either have ulcers over the top of the hernia, skin grafts or open wounds where you’re going to have a real thin skin over the top of your mesh. This is certainly going to make the likelihood of a mesh infection much higher. So, approach these patients open, resect the ulcer, take out the skin graft and do what is necessary to get better tissue coverage of the mesh.
Patients with loss of domain. These patients have more of the abdominal contents outside of the abdominal cavity than inside of the abdominal cavity. Obviously, those can be massive hernias and those aren’t very well-suited to laparoscopic approach just because there is not enough working space to do the repair.
Patients with infected mesh or an enterocutaneous fistula. In these patients where you are anticipating having to enter the bowel, or if it’s already an infected case where the patient has bacterial contamination, then the use of synthetic mesh is not indicated. Laparoscopy would not be beneficial. These patients are best served with open mesh removal or a bowel resection with abdominal wall reconstruction utilizing a biologic graft reinforcement or some sort of tissue-based repair combined with a components release.
Dr. Siegel: The two areas where there may be added benefit of a laparoscopic approach for inguinal hernia repair, as recommended by the American College of Surgeons (ACS), is for recurrent hernias that have already been repaired anteriorly or if there is bilaterality to the hernia. I still use an open anterior technique for bilateral hernias because it has not proven to decrease pain and I know I have a low recurrence rate. However, when we have two or three recurrences anteriorly, we will then go laparoscopic or just open preperitoneal for those repairs.
Surgical Products: Regardless of technique, what are some challenges surgeons face in hernia repair, and how have surgeons dealt with these challenges?
Dr. Siegel: It all comes down to two things: recurrence rates and pain. In experienced hands, an anterior inguinal hernia recurrence should occur in one percent or less of patients. As far as pain control, that’s going to be the biggest differentiation because you can do two or three different repairs and get a low recurrence rate. What you want to do is now that everyone is getting close to the same recurrence rate is have your patient in less pain, allowing them to get back to work and their regular activities sooner.
Dr. Cobb: The biggest concern with ventral hernia repair is mesh infection. This complication results in significant morbidity and need for additional procedures. Ninety percent of these mesh infections are Staphylococcus aureus and a significant number of those are Methicillin-resistant Staphylococcus aureus (MRSA). The cause of the infection is usually skin contaminants at the time of placing the mesh. It’s not like the surgeon forgot to wash his/her hands or the instruments are dirty. Mesh contamination typically occurs at the time of placement from bacteria that normally reside on the patient's skin.
Laparoscopy has several benefits with regard to mesh infection. The size of the incision and the amount of tissue dissection are limited compared to open technique. With laparoscopy, many times you can bring the mesh through the trocar so you never expose the prosthetic to the patient’s skin. That’s the reason why the risk of mesh infections is less than one percent in most of the large laparoscopic series for ventral hernia repair.
Surgical Products: The topic of biologics is getting a lot of discussion among surgeons performing hernia repairs. What is your experience using biologics?
Dr. Cobb: For a while, there was a lot of interest in biologic mesh for abdominal wall reconstruction and there was widespread use. Now as we start to get some clinical follow up, I think surgeons are taking a step back and perhaps looking more critically at biologic grafts. The cost of these materials prohibits routine use, particularly in clean cases where synthetic mesh will suffice. As it currently stands, you should not bridge a defect with a biologic due to the high incidence of bulging and/or recurrence. With the standard approach to a laparoscopic ventral hernia repair, you’re bridging the gap, so in that application, biologics should not be used.
Still, there are times when biologics must be used and synthetics cannot. For example, in cases of active infection or with contaminated procedures, such as concomitant bowel resections, there is a role for biologic grafts or bioabsorbable mesh. In these instances, I prefer an open components separation and reinforce that closure with a biologic graft or bioabsorbable mesh. I will close the posterior layer of rectus fascia or preperitoneum, lay a biologic or bioabsorbable in the retrorectus space and then close the anterior fascia over the graft. There is certainly a role for biologics and professionals in the industry are investigating how to make them more durable for the future.
Dr. Siegel: Biologic materials come into play for me in two major areas:
1. Where I’m having trouble closing an abdominal cavity, where I had a bowel perforation or major contamination. You don’t want to put in a permanent mesh that is going to get infected because that is going to need to be removed in the future. That has been the one area for me where biologics have been a good option, and allows us to get these patients’ abdomens closed.
2. The other area probably would be in components separations, where people have had major abdominal surgery and they have huge hernias that take up the entire abdominal wall. What we do is we free everything up and bring everything together. The biologic mesh is good to be able to get a mesh in and give our repair added strength without too much added infection.
Surgical Products: Along with biologics, there is an abundance of synthetic meshes to choose from when repairing hernias. How should surgeons choose the best material to use?
Dr. Cobb: It depends on the approach. The choice you make for a laparoscopic repair can be different than for an open repair. The reason is that you’re placing the mesh in a different space. For a laparoscopic repair or open intra-abdominal placement of mesh (IPOM), you’re putting the mesh inside the abdomen, so you need a mesh that is not going to cause a lot of adhesions or fistula formation to the underlying bowel or viscera.
For mesh in an intra-abdominal position, it is going to need a mesh with a protective layer, whether that’s expanded polytetrafluoroethylene (PTFE) which has very good anti-adhesion characteristics, or polyester- or polypropylene-based materials that have some sort of absorbable barrier. Essentially, you take a non-absorbable mesh and then put some sort of absorbable coating on it so that it doesn’t, in theory, form bad adhesions to the bowel.
For open procedures, the preference is to place the biomaterial in the layers of muscle wall, either in the retrorectus space or in the preperitoneal space.
Theoretically, the mesh is not in contact with the viscera, so a mesh that is going to incorporate or grow into the muscle layers well is preferred. That is typically polypropylene- or polyester-based meshes. I don’t use PTFE-based materials for open repairs just because it can be quite difficult if you have a wound complication or if you have a potential wound or mesh infection. You can’t clear the infection. You almost always have to remove the mesh. The macroporous, lighter weight materials are better suited for open repairs.
Dr. Siegel: Meshes for years were sutured in or stapled in place. This would cause tension, pulling, tugging and nerve entrapments that could cause long-term pain for these patients. I have since changed to a self-fixating mesh that no longer needs to be sutured or stapled in place. As far as short term, without the tugging, pulling and suturing, I am seeing less pain when patients come for their first visit one week after the procedure and for their long-term follow up, as well. I have also found it helps decrease in time in the OR by 10 to 15 minutes a case and it is reproducible, meaning I can train residents to do the procedure using the mesh on their own and not feel like they’re doing any less of a job than someone who’s been doing it for 15 to 20 years.
Looking To The Future
Surgical Products: From a surgeon’s perspective, what does the future hold for the materials used to repair hernias?
Dr. Cobb: From a biomaterials standpoint, I think we can use the macroporous, lighter weight materials more than we think we can. Currently, when someone has a bowel resection or ostomy reversal, the teaching is you do not place a synthetic mesh due to contamination. However, I think we can use some of these lighter weight macroporous materials and the risk of infection would be pretty low.
Dr. Siegel: The different meshes out there are so good now, I am sure they’re still working on making better meshes. As far as inguinal hernia repair, I think we’ll see more and more of the self-fixating mesh being developed and used.
Surgical Products: Are there any other future developments in hernia repair in which surgeons should be aware?
Dr. Cobb: I think the future is mostly going to focus on trying to prevent hernias. I think the emphasis is going to be prophylactically placing mesh in high-risk patients to try to prevent hernia formation in the first place. For example, these patients would include those who have COPD or aortic aneurysm disease because we know those patients are at very high risk for forming abdominal wall hernias.
Further, we currently do not know how to best deal with patients that have mesh infections. Right now, when patients have had ventral hernia repairs complicated by mesh infections, the thought is you should never put a synthetic back into that patient, particularly if they have a MRSA infection. Those people are better suited for biologic grafts. As we learn more about lightweight, macroporous meshes, it will be interesting to see how our approach to handling mesh infections evolves in the future.