Chapter 8A. Perspective on Hernias: Laparoscopic Incisional Hernia

Incisional hernias are an all too frequent complication of laparotomies and surgeons spend a significant part of their practice repairing such defects. Leblanc and Booth published the first report of laparoscopic incisional hernia repair in 1993.1 Over the course of time, this approach has gained popularity with patients who seek a “minimally invasive” solution to their hernia problem and with surgeons who believe that the laparoscopic approach offers advantages over traditional repairs.

After nearly two decades of experience with laparoscopic incisional hernia repair, there is a surprising paucity of good data clearly proving the benefits of this technique over standard open surgery. In this chapter, we will review the published experience, technical factors needed for successful laparoscopic repairs, the costs, and long-term results of laparoscopic ventral hernia repair (LVH). Since most ventral hernias are small and easy to repair primarily, we will focus on incisional hernias and use the term LVH to cover both types of defect.

Although the pioneers of LVH felt that this approach would be less invasive and therefore less painful than traditional surgery, many other advantages became apparent as the procedure was developed. Traditional incisional hernia repairs—even when performed with mesh—have a relatively high failure rate. Some of the failures are due to patient-related factors such as obesity, steroid use, tobacco abuse, or abdominal stressors such as chronic cough. However, one of the most common technical causes of failure is failure to identify all fascial defects. Many incisional hernias have multiple components, some of which are not apparent on physical examination. If a surgeon fails to repair all the defects, failure (occasionally described as a new hernia defect in proximity to the prior repair) is almost certain to occur. LVH offers a superior view of the fascial defect and hence reduces the likelihood that a surgeon will fail to identify the extent of the problem that needs to be fixed. This is particularly helpful when the fascia is attenuated. An additional advantage is gained in patients who have undergone surgery for abdominal neoplasms in that peritoneoscopy may occasionally discover signs of recurrent disease. Finally, in patients whose incisions are deeply scarred, approaching the defect transperitoneally can avoid a tedious dissection of the subcutaneous layers. Likewise, if a patient has had a prior wound infection, the transperitoneal approach delivers the mesh prosthesis through a clean field and may reduce the risk of recurrent infection.

There are disadvantages of LVH that need to be considered when recommending treatment to a patient. Since very little is done to the subcutaneous tissue, LVH often leaves a large dead space that can result in a seroma. Even if seroma formation is prevented, excess skin and fat can lead to a poor cosmetic outcome following repair of large defects. Some patients in whom LVH is attempted may have severe adhesions necessitating a tedious and occasionally hazardous adhesiolysis. Inadvertent bowel injury is probably the leading cause of mesh infection in LVH and can be a devastating complication if it is not recognized and repaired promptly. Lastly, some locations in the abdomen preclude transfascial fixation of the mesh and hence may be more prone to failure of the repair than when the defect is centrally located (Table 8A-1).

It is well established that the use of prosthetic mesh reduces the rate of long-term recurrence in open incisional hernia repairs compared with suture repair alone.2,3 Although suture hernioplasty has been described in laparoscopic surgery, it is technically more difficult than mesh hernia repair and violates the principle of a tension-free technique.4 Therefore, laparoscopic hernia repair is almost uniformly performed with a mesh prosthesis.

In LVH, the mesh is placed in direct contact with the viscera. As in open inlay repairs, this carries the risk of development of chronic inflammation, fistula, infection, and mesh migration.5 To minimize these risks, dual-sided mesh prostheses have been developed and should be utilized in LVH. These implants are coated with materials designed to prevent adhesion formation on the side exposed to the viscera. Animal studies have demonstrated good short-term results; nevertheless, there are few human studies evaluating long-term results that compare different types of mesh.6,7

Both open repair and LVH require clear identification of the hernia defect to place and fix the mesh properly. LVH replaces a large incision and an extensive dissection of the subcutaneous tissue with adhesiolysis, peritoneal dissection, and intra-abdominal reduction of the contents of the hernia sac. Paradoxically this minimally invasive approach may be more invasive than an open repair because of the extent of peritoneal and visceral trauma. This paradox may explain in part the limited advantage (if any) of LVH in reducing postoperative pain.8,9 Indeed, in most of the randomized controlled trials (RCTs) and meta-analyses where postoperative pain and/or quality of life were evaluated, no significant differences between open repair and LVH were identified.10,11 Different techniques of laparoscopic mesh fixation have also been evaluated with no significant differences in postoperative pain or quality of life.12

When extensive intra-abdominal dissection is required in the laparoscopic approach to access and/or identify the defect and place the mesh, it almost certainly accounts for the higher number of bowel injuries observed in laparoscopic technique compared with open surgery.8,10,13,14 In LeBlanc's 2007 review article, the overall incidence of enterotomy secondary to incisional and ventral hernia repairs was 1.78% (72 out of 3925 patients). Patients who sustained this complication had an increase in mortality rate compared with those who did not have an enterotomy from 0.05% to 2.8%.15

As with any new procedure, the learning curve needs to be surmounted. A common mistake a novice surgeon is apt to make is failure to get adequate overlap of the mesh with normal tissue in covering the defect. While adhesiolysis can be performed at typical pneumoperitoneum pressures of 15 mm Hg, sizing the mesh should be done with the abdomen nearly deflated. If the mesh is measured with the abdomen fully distended, it will be lax once the pneumoperitoneum is released and patients may feel as if their hernia was never fixed! As Brooks et al point out in their chapter, transfascial fixation sutures are a vital component for good mesh fixation. The larger the mesh, the more sutures are needed in our opinion. Tacks should be placed between the fixation sutures to prevent herniation of viscera between sutures. Postoperatively, patients should be instructed to wear abdominal binders—particularly if a large defect has been repaired—in an effort to obliterate dead space and prevent seroma formation.

In contrast to many other laparoscopic procedures, LVH may not always reduce postoperative pain. As was previously discussed, immediate postoperative pain and quality of life appear to be similar after laparoscopic and open ventral hernia repair. Nevertheless, there are other postoperative outcomes where LVH offers advantages.

Most of the RCTs, meta-analyses, and comparative studies show a significantly lower rate of short-term postoperative complications after LVH compared with open surgery.9,11,13,16,17 Detailed analysis of postoperative complications shows that this reduction is primarily due to fewer wound-related complications. In the article published by Itani and colleagues, postoperative complications were observed in 31.5% of a laparoscopic group and 47.9% of an open group of patients with an incidence of wound infection of 2.8% and 21.9% in laparoscopic and open hernia repair, respectively.13 This is an important outcome because surgical site infection may require mesh removal. In the meta-analysis published by Forbes et al, the rate of mesh removal secondary to infection was 0.7% in LVH and 3.5% in open surgery.17

It is interesting that although postoperative pain is similar, hospital stay is shorter for patients undergoing LVH in most, but not all, the randomized controlled studies.17 Some studies, such as the one published by Itani and colleagues that did not find a reduction in hospital stay (4.0 vs 3.9 in laparoscopic vs open surgery, respectively), did however find that LVH patients returned to work more rapidly than those undergoing open repairs (23 vs 28 days).

In summary, the overall incidence of postoperative complications is reduced after laparoscopic hernia repair mainly due to a lower incidence of wound-related complications. While short-term pain and quality of life appear to be similar, hospital stay and return to work appear to be shorter in LVH compared with open surgery.

The most important outcome in hernia repair surgery is recurrence. The introduction of mesh in open hernia repair was a major advance that substantially reduced the recurrence rate.2,3 Burger et al reported a 10-year cumulative rate of recurrence of 63% and 32% for suture and mesh hernia repair, respectively. Based on the data currently available, the rate of hernia recurrence after open and laparoscopic hernia repair is at least similar.9,10,13,18 Unfortunately, most of the trials comparing LVH and traditional repairs were designed to evaluate postoperative complications, not long-term recurrence. Hence, there is little, if any, published follow-up beyond 3 years. A meta-analysis published in 2009 that analyzed eight RCTs found no significant difference in the risk of hernia recurrence between both techniques at short term of follow-up (3.4% and 3.6% in laparoscopic and open repair, respectively).17 Similar findings were recently published by Itani and colleagues.13 In this RCT, the recurrence rate at 2 years of follow-up was 12.5% for the laparoscopic repair group and 8.2% for the open technique group (p = 0.44). In open hernia repairs, the recurrence rate is lower when the procedure is performed by experienced surgeons.19 It is logical to expect that the same relationship exists between LVH and surgeon volume.

The laparoscopic technique of hernia repair involves the use of laparoscopic instruments and potentially new, expensive mesh prostheses that must be added to the standard cost of operating room use and hospital stay. In open hernia repair, the use of mesh has been shown to be a cost-effective alternative to suture repair when one accounts for postoperative complications, recurrence rate, and long-term follow-up.20 There is little data available for LVH. This is an issue that should be incorporated in future trials. It is impossible to compare the cost/benefit ratio of LVH to standard repairs without this information.

LVH is a well-established technique for treating abdominal wall hernias. It is hard to make a blanket statement that LVH is a superior approach to traditional mesh repairs. However, understanding the unique features of the approach allows well-trained surgeons to utilize it where it is most likely to be beneficial and likewise opt for a traditional mesh repair when LVH is unlikely to offer any advantage. The modern surgeon treating abdominal wall hernias should be facile with both techniques.