Intraperitoneal Mesh Repair for Incisional Hernia

Abstract

Incisional hernias remain an important postoperative complication of any procedure involving a laparotomy incision. Although most incisional hernias remain asymptomatic, incarceration and strangulation are emergent complications requiring prompt diagnosis and intervention. Mesh repair has become widely favored over simple suture repair of abdominal fascial defects in recent decades, though recurrence of incisional hernias remains high. Despite the advent of laparoscopic approaches to hernia repair, open approaches are utilized when numerous adhesions are encountered, laparoscopic access is unsafe or when laparoscopy is not readily available. We present an open surgical repair of a large incisional hernia involving the abdominal midline and parastomal site in a woman with a history of laparotomy and colostomy with a subsequent reversal for a perforated colon.

Case Overview

Background

An incisional hernia is a common short-term and long-term complication of abdominal surgery, occurring in approximately 10–15% of patients with any type of abdominal incision.¹ Incisional hernias occur due to failure or degeneration of fascial closure at the prior surgical site, resulting from a combination of patient and technical risk factors, including age, obesity, smoking status, immunosuppression, infection, and suboptimal fascial closure.^2–4 Depending on the patient acuity, they may be managed expectantly or operatively using open or laparoscopic approaches to reduce the hernia contents and reinforce the site of closure, commonly using a synthetic or biologic mesh.

Focused History of the Patient

This patient is a native Honduran woman who presented with persistent abdominal pain and intermittent obstructive symptoms, including nausea, abdominal cramps, and bloating. The patient had an extensive surgical history with multiple laparotomies, including emergency exploratory laparotomy and diverting colostomy for colonic perforation with subsequent reversal. Given her presentation and history, she underwent surgical evaluation for one or more incisional hernias from these procedures.

Physical Exam

The patient presented with a hernia defect appreciated manually along the abdominal midline. Palpation of the prior stoma site also suggested an additional parastomal hernia, which was confirmed intraoperatively.

Patients with an incisional hernia commonly notice a palpable bulge at the site of prior surgery, as in this patient. In general, the patient may be asymptomatic and/or view the herniation primarily as a cosmetic concern, or may present with various symptoms including nausea, vomiting, or a painful mass that increases in size with straining or other maneuvers that increase intra-abdominal pressure.^2,5 Clinical examination is sufficient for diagnosis in most non-obese patients.

Imaging

Imaging was not obtained for the current patient based on clinical features and size on physical examination. In general, CT imaging can be used to confirm the presence of an incisional hernia in patients where presentation is ambiguous, such as in obese patients. In resource-rich settings, patients with large complex ventral hernias >10 cm in size or patients with a significant loss of domain (>20–30% of abdominal contents) should undergo preoperative CT imaging,⁶ as the risk of abdominal compartment syndrome is higher with a large reduction of hernia sac contents, and advanced abdominal wall reconstructive techniques may be required.

Natural History

Many incisional hernias will remain asymptomatic and not require further intervention, with watchful waiting identified as a safe approach to management.^7–10 However, as with most hernias, incisional hernias can present with evidence of incarceration and/or strangulation of bowel and abdominal contents.  Incarceration results when the hernia sac and its contents become irreducible, and may lead to bowel obstruction in 10–15% of cases.¹¹ Strangulation occurs when the blood supply to the hernia sac contents becomes compromised as a result of local pressure against the vessels supplying the organs. Prompt diagnosis and surgical intervention is required to prevent necrosis of tissue and the need for bowel resection.

Options for Treatment

For asymptomatic incisional hernias, nonoperative management is an acceptable option for patients who do not desire repair, and watchful waiting is advised. Asymptomatic patients or symptomatic patients without evidence of incarceration or strangulation may undergo elective repair once they are medically optimized for surgery.¹² Symptomatic patients with incarceration or strangulation of the hernia require emergency repair to ensure the viability of the hernia sac contents.

For elective repairs, the size of the incisional hernia determines the available options for the closure of the defect.¹² Generally, mesh repair is suggested for the repair of all incisional hernias regardless of size due to the high likelihood of recurrence with suture repair of these defects. In clean surgical fields, mesh repairs are typically desired for durability of repair long-term, especially for hernias > 2 cm.  

Non-mesh repair or primary tissue repair with sutures may be attempted in patients concerned about mesh-related complications, as long as the patient understands the elevated risk of recurrence. Non-mesh simple suture repair is associated with increased rates of recurrence above 50% vs. approximately 20% with mesh repair.^13–16

Rationale for Treatment

This patient has an extensive surgical history including diverting colostomy with subsequent reversal. She presented to our clinic with abdominal pain and intermittent obstructive symptoms. On examination, there was a palpable midline bulge that protruded upon straining, suggestive of one or more incisional hernias over the abdominal midline and possibly over the stoma site. As the defect was perceived to be large on examination, an open approach with intraperitoneal mesh repair was preferred to reduce the herniated contents and close the defect in the fascial layer.

Discussion

The patient underwent successful open hernia repair with intraperitoneal mesh placement. Intraoperatively, a midline abdominal defect was identified, along with an adjacent parastomal hernia that had been suspected on physical examination. In both locations, the herniated contents were reduced, and the hernia sac was excised. The combined defect measured 15 x 13.5 cm and was corrected by suturing an intraperitoneal 20 x 15 cm synthetic mesh in underlay position into the fascial layer surrounding both hernias. Primary suture closure of the overlying fascial layer was performed, and a drain was placed to prevent seroma formation.

Incisional hernias remain an important postoperative complication of any procedure involving a laparotomy incision. The incidence of incisional hernias increased dramatically in the United States during the 20th century, as surgical advances resulted in a greater number of laparotomies performed.¹⁷ As of 2015, 4–5 million laparotomies are performed each year in the U.S., and it is estimated that the incidence of incisional hernias following these procedures may be as low as 3% or as high as 50%, with the best estimates suggesting rates of approximately 10–15%.¹⁸ Nearly half of all incisional hernias occur within the first 2 years after surgery, with 74% occurring within 3 years.¹⁶

An open approach with simple suture repair was the standard procedure for correcting all ventral and incisional hernias prior to the mid-1990s.¹⁷ Recurrence was common, and primary suture repair is associated with recurrence rates of greater than 50%.^13–16 In recent years, mesh repair has become widely favored for the vast majority of ventral hernias due to a significant reduction in recurrence rates. Luijendijk et al. (2000) demonstrated that mesh repair was superior to primary suture repair for all midline abdominal hernias, with a recurrence rate of 24% after 3 years.¹⁵ However, other studies have linked mesh repair to slightly increased rates of reoperation for mesh-related complications.^19,20

Synthetic and biological meshes are the primary options available for mesh repair. Synthetic meshes are preferred in the majority of clinical situations and are derived from either extruded monofilament or expanded polytetrafluoroethylene (ePTFE).¹² Biological meshes may be preferred in the setting of a contaminated or infected field, although this practice is currently debated.^21,22 Biologic meshes are derived from human or animal tissues that are washed repeatedly to remove traces of immunogenicity and can ultimately grow into native tissue, eventually replacing it. Long-term data for biologic meshes is currently lacking. 

Mesh placement may be performed in an onlay, inlay, sublay, or underlay position in relation to the anterior fascial layer. Following resection of the hernia sac and fascial edge approximation with simple suture repair, mesh placement in an onlay location anterior to the anterior rectus sheath has historically been associated with an increased risk of wound complications and infection²³ but is technically easier and is regaining popularity in some regions.^{24, 25} Inlay repair connecting the mesh layer directly to the edges of the fascia is typically avoided and is reserved for situations where the fascial defect is too large to close by other means. Open sublay mesh repair for midline defects, first described by Rives and Stoppa,²⁶ involves placement of the mesh anterior to the posterior rectus sheath and posterior to the rectus muscle. Underlay positioning or intraperitoneal onlay mesh (IPOM) places the mesh intraperitoneally with subsequent primary suture closure of the overlying fascia in open repairs.¹² Laparoscopic approaches primarily employ the underlay positioning technique. A systematic review of 62 studies demonstrated reduced recurrence and complication rates for open repairs using sublay or underlay when compared with onlay or inlay mesh placement.²⁷

Leblanc and Booth (1993) introduced the laparoscopic approach to incisional hernia repair as an extension from laparoscopic repairs being performed for inguinal hernias.²⁸ Since then, laparoscopic approaches have grown in popularity, though currently only about 25% of incisional hernias are repaired laparoscopically,^29,30 despite evidence suggesting reduced infection rates, shorter recovery, less pain, and comparable or improved recurrence rates over open surgery.^31–34 A 2014 review of 1003 patients demonstrated decreased incidence of wound drainage and wound infection for laparoscopic incisional hernia repairs compared with the open approach.³³ Nevertheless, it is thought that laparoscopic repair may be unnecessarily invasive for patients with readily identifiable small-sized (<4 cm) hernias, and it is relatively contraindicated for very obese individuals and/or patients with significant loss of domain through the hernia defect. Hernia defects greater than 10 cm are unlikely to be closed laparoscopically, and an open approach to repair is preferred.¹² Hernias measuring 4–10 cm are most optimal for laparoscopic mesh repair, depending on surgeon preference and level of comfort. 

For large hernias >10 cm or hernias with a significant loss of domain in which the majority of abdominal contents lie outside of the abdominal cavity, component separation is an option to achieve the closure of the fascial defect under physiologic tension. This technique separates portions of the anterior abdominal musculature to advance the rectus abdominis into a midline position where primary suture closure of the fascia can be achieved, preserving abdominal wall function. Component separation can restore anatomy and functionality for defects up to 20 cm wide at the level of the umbilicus.³⁵ However, it is relatively contraindicated in patients with the disruption of the abdominal musculature, the compromise of the superior epigastric and/or deep inferior epigastric arteries, or active infection or the contamination of the operative field. Mesh placement is advised as supplementary reinforcement despite a relative paucity of research in outcomes after component separation with hernia repair.^36–38 Data on preferred mesh positioning with component separation is also less clear, but sublay positioning is often preferred.^35,39

Following mesh placement using either laparoscopic or open approaches, subsequent primary fascial closure should be routinely performed as it is associated with decreased rates of seroma formation, fewer adverse events, and shorter hospital stays.⁴⁰ 

Closed suction drains are commonly placed following incisional hernia repair and are nearly universally used for the repair of large hernia defects. A 2014 Cochrane review determined that current data is insufficient to support or refute this practice despite its popularity.⁴¹

Research into ventral hernia repair and midline incisional hernias is currently targeted toward the use of biologic meshes, advanced component separation techniques, and mesh placement, as discussed above. Recurrence rates remain high overall at greater than 20% with mesh repair despite significant improvement over simple suture repair. Morbidity associated with incisional hernia repair is low, with an incidence of infection generally 5% or less, though it is higher for large, complex hernias and/or hernias in morbidly obese patients.⁴²

Equipment

No special equipment was used in this case.

Disclosures

Nothing to disclose.

Statement of Consent

The patient referred to in this video article has given their informed consent to be filmed and is aware that information and images will be published online.