IT'S WHAT'S INSIDE Are you using hernia meshes composed of biologic materials or impregnated with antimicrobials? If so, you're fighting infection risk more effectively.

The incidence of surgical site infections is statistically low for hernia repairs with mesh. Some of the credit goes to the infection-fighting properties of mesh itself. From biologic mesh embedded with antimicrobials to bio-synthetic mesh that the body breaks down over time, more and more of today's hernia surgery products are engineered to prevent infection. Here's what the latest research tells us about mesh technologies and infection.

1. Biologic-based meshes
Devices from the new generation of biologic-based meshes are partially absorbable — a composite of flexible polypropylene and a matrix derived from pig, fetal calf, horse dermis and even human tissue. This type of technology has been successful in chronic wound care, and the principles carry over with internal implantation of these large-pore meshes.

In a poster at this year's Society of American Gastrointestinal and Endoscopic Surgeons annual meeting, Zemlyak et al. reported on use of a newer, biologic-based mesh for ventral and inguinal hernia repairs, and the results of implantation. The researchers found that the biologic mesh was well-tolerated by patients undergoing both procedures and was "associated with a low rate of complications" — just 3% incidence of superficial surgical site infection — "and favorable quality of life outcomes. No recurrences were observed at 6 months of follow up."

2. Antimicrobial impregnation
Meshes that contain antimicrobial preservatives are active against a broad spectrum of microbes, and can decrease the risk of infection. According to Dorion and Gruber, expanded polytetrafluoroethylene mesh "impregnated with antibiotics has been shown in laboratory studies to minimize bacterial adherence. Antibiotic-coated mesh may reduce the risk of mesh infection but has never been demonstrated in a clinical trial." Lab studies have shown these kinds of meshes to be effective against methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphylococcus epidermidis, Candida albicans, group A Streptococcus and Acinetobacter baumannii.

3. Endoscopic staplers
Several studies have reported reduced rates of incisional SSIs when endoscopic staplers are used in favor of manual suturing in abdominal procedures. You can use these stapling devices for inguinal and ventral hernia repairs, soft-tissue approximations and skin closures. In addition to lowering infection risk, some of the new staplers let surgeons secure the mesh and close the skin with the same device — no separate skin stapler needed.

DON'T OPEN TILL SURGERY Keep the mesh patch in its original packaging until it's time for use.

Quick Tips

4 Easy, Everyday SSI-Fighting Practices

Incidence of surgical site infection remains statistically low for hernia repairs with mesh. However, it's still a foreign object and, once bacteria sets in, there are no biological or clinical pathways for antibiotics to reach the diseased prosthetic. Here are 4 pre- and perioperative surgery tasks to help protect your hernia patients against infections.

• Meticulously cleanse the patient's skin at the surgical area — douse multiple times if warranted.
• Administer intravenous prophylactic antibiotics about an hour before surgery in your highest-risk patients.
• Protect the patient's skin with a drape to avoid hand contact by the surgeon or members of the surgical team.
• Keep the mesh patch in its original packaging until it's time for use. Opening the package at the onset of a 2-hour operation merely invites potential contamination.

When it does occur, infection always becomes an ordeal. It's a complication that not only has a messy outcome for the patient — who faces longer recovery and increased pain — but definitively adds to institutional recovery costs, because patients remain hospitalized longer and have higher rates of readmission. Prevention, therefore, is the key.

— Guy Voeller, MD, FACS

Dr. Voeller ([email protected]) is a professor of surgery at the University of Tennessee Health Center in Memphis and past president of the American Hernia Association.

4. Laparoscopic approach
Your best protection against SSIs associated with hernia repair may not be what you use, but how you do it. According to a poster presented at the 2012 SAGES annual meeting by Jones, St. Hill and Tusda, the laparoscopic approach minimizes risk of infection when compared with the open surgical procedure. The researchers set out to compare the incidence of surgical site infection in laparoscopic approaches and open inguinal hernia repairs. All patients who were part of the assessment received single-dose prophylactic antibiotic; the researchers followed up at 90 post-operative days to determine how many patients in both groups had developed infections. Infection at the site and mesh infection (any infection that necessitated removal of the mesh) were recorded.

Both groups had a 0% mesh infection rate at 90 days. Laparoscopic inguinal patients exhibited a 1% SSI rate, compared with nearly 5% in the open group. The researchers concluded that "routine antibiotic prophylaxis for prevention of surgical site infection may not be necessary for laparoscopic inguinal herniorraphy, given the low incidence of mesh or surgical site infection."

5. Institute antibiotic prophylaxis
Although the laparoscopic approach provides protection against infection, for patients with certain infection risk factors, the use of antibiotic prophylaxis is recommended. According to the literature, you should screen for the following factors:

• steroid therapy,
• smoking,
• prolonged operative time,
• diabetes,
• use of absorbable mesh,
• the procedure's being a stopover on the way to a more complex procedure,
• drain placement,
• obesity, and
• prior wound infection.

According to Lawrence and Kim, prior wound infection is also the prime risk factor for hernia recurrence — which is often caused by SSI — posing an 80% chance of putting the patient back in the same position.