When to use mesh in repairing incarcerated hernias?

Mesh Use in Incarcerated Hernia Repair: Decision Algorithm Based on Surgical Field Classification

For incarcerated hernias, mesh repair is recommended in clean and clean-contaminated surgical fields (CDC classes I and II) due to significantly lower recurrence rates, while primary repair is preferred in contaminated or dirty fields (CDC classes III and IV) to prevent mesh-related infections.

Decision Algorithm Based on CDC Wound Classification

CDC Class I (Clean Surgical Field)

• Use synthetic mesh for all incarcerated hernias without signs of intestinal strangulation or concurrent bowel resection 1
• Mesh repair significantly reduces recurrence rates compared to tissue repair without increasing wound infection rates 1, 2
• This applies to both ventral and groin hernias 1

CDC Class II (Clean-Contaminated Field)

• Use synthetic mesh even with intestinal strangulation and/or concomitant bowel resection without gross enteric spillage 1
• Emergent prosthetic repair with synthetic mesh can be performed without increased 30-day wound-related morbidity 1
• Multiple studies show no significant increase in surgical site infections with mesh use in this setting 1, 3

CDC Class III/IV (Contaminated/Dirty Field)

• For small defects (<3 cm) with bowel necrosis and/or gross enteric spillage, use primary repair without mesh 1, 4
• When direct suture is not feasible for larger defects, consider biological mesh 1, 4
• Choose between cross-linked (more resistant to mechanical stress) and non-cross-linked biological mesh based on defect size and contamination degree 1
• If biological mesh is unavailable, consider polyglactin mesh or open wound management with delayed repair 1

Special Considerations

Laparoscopic vs. Open Approach

• Laparoscopic repair can be performed for incarcerated hernias without signs of strangulation or need for bowel resection 1
• Open preperitoneal approach is preferable when strangulation is suspected or bowel resection is needed 1
• Diagnostic laparoscopy (hernioscopy) can be useful to assess bowel viability after spontaneous reduction of strangulated groin hernias 1

Bowel Resection Considerations

• In clean-contaminated fields (bowel resection without gross spillage), synthetic mesh remains safe 1
• However, recent meta-analysis shows increased surgical site infection risk with mesh when bowel resection is performed 5
• Consider this increased risk when deciding on mesh placement in cases requiring bowel resection 5

Unstable Patients

• For patients with severe sepsis or septic shock, open management is recommended to prevent abdominal compartment syndrome 1
• Intra-abdominal pressure may be measured intraoperatively 1
• After patient stabilization, attempt early definitive closure of the abdomen 1

Antimicrobial Considerations

• For CDC class I (clean field): short-term prophylaxis is recommended 1
• For CDC classes II and III (clean-contaminated and contaminated): 48-hour antimicrobial prophylaxis is recommended 1
• For CDC class IV (dirty field): full antimicrobial therapy is recommended 1, 4

Outcomes and Complications

• Mesh repair significantly reduces recurrence rates compared to primary repair (0-4.3% vs. 19-21.4%) 2, 6
• Surgical site infection rates with mesh in clean and clean-contaminated fields range from 0-9.4% 3, 7
• Most mesh infections can be managed with drainage and local wound care without mesh removal 3, 7

Clinical Pitfalls to Avoid

• Don't avoid mesh in clean or clean-contaminated fields due to fear of infection - evidence shows it's safe and reduces recurrence 1, 3
• Don't use synthetic mesh in grossly contaminated fields (CDC class III/IV) as infection rates can be as high as 21% 4, 5
• Don't underestimate the importance of appropriate antimicrobial prophylaxis based on wound classification 1
• Don't neglect to consider the size of the defect when choosing between primary repair and mesh placement 1, 4