**6.3 Sugical site infections**

The definition of Surgical site infections (SSIs) according to the criteria developed by the Centers for Disease Control and Prevention include every SSI up to 30 days after the operation [17]. Infections are categorized as incisional (superficial or deep) infections or organ–space infections. Superficial SSIs involve only skin and subcutaneous tissue and exclude stitch abscesses. Deep SSIs involve deeper soft tissues at the site of incision. Organ–

space SSIs are defined as infections in any organ or space. In laparoscopic incisional hernia repair the incidence of SSI is low. In a meta-analysis of 8 randomized controlled trials Forbes et al. showed a significant reduced risk of surgical site infections in laparoscopic incisional hernia repair compared to open surgery [18]. The extensive tissue dissection which is associated with the open approach explains the significant higher infection rate in open surgery. Mostly SSIs in laparoscopic surgery are superficial and can be treated conservatively. Mesh removal due to an surgical site infection is very rare [19].

#### **6.4 Enterotomy**

186 Updated Topics in Minimally Invasive Abdominal Surgery

**Lap. group n = 69**

Intestinal fistula 0 (0) 1 (1.8) n.s. Hospital stay (days)\* 6 (1-23) 7 (1-67) 0.014

Recurrence 11 (15.9) 10 (17.9) n.s.

Return to work (weeks) 3 (0-50) 6 (0-28) n.s. Pain at follow-up (VAS) 0.6 (0-6) 0.5 (0-5) n.s.

We showed that laparoscopic incisional hernia repair is feasible and safe even in patients

The conversion rate to open surgery depends on the surgeons experience, the surgical skills, and intraoperative complications such as bowel lesions or bleeding. In the literature conversion to open surgery is mostly due to adhesions, with an overall conversion rate of 10-15% [12, 13]. However, complete adhesiolysis is very important especially in large incisional hernia to gain enough place for the mesh fixation and therefore to minimize the

There is a wide range in duration of the operation comparing laparoscopic and open incisional hernia repair. Most studies revealed that operation time in laparoscopic incisional hernia repair is longer compared to open surgery [12-14]. However, there was always a statistically difference in all these studies. Longer operation time can be explained with the learning curve in laparoscopy. Furthermore the fixation technique of the mesh can be time consuming especially in large incisional hernia repair. On the other hand there are some studies with no difference or even a shorter operation time in

The definition of Surgical site infections (SSIs) according to the criteria developed by the Centers for Disease Control and Prevention include every SSI up to 30 days after the operation [17]. Infections are categorized as incisional (superficial or deep) infections or organ–space infections. Superficial SSIs involve only skin and subcutaneous tissue and exclude stitch abscesses. Deep SSIs involve deeper soft tissues at the site of incision. Organ–

Values in parentheses are percentages unless indicated otherwise. \* Values are median (range).

Table 2. Results of outcome parameters of large incisional hernia repair

**5.3 Incisional hernia after liver transplantation** 

under immunosuppressive therapy [12].

**6. Postoperative outcome 6.1 Conversion to open surgery** 

recurrence rate.

**6.2 Operation time** 

laparoscopic surgery [15, 16].

**6.3 Sugical site infections** 

SSI 4 (5.8) 16 (26.8) 0.006

**Open group n = 56**

*P***-Value**

In general the mortality rate of laparoscopic incisional hernia repair is low with 0.05% [8]. The most serious complication during laparoscopic incisional hernia repair is enterotomy [8]. Enterotomy occurs during adhesiolysis or as a burning lesion with the electorcauter. Therefore we avoid electrocauterisation during adhesiolysis to prevent bowel lesions and perforation. The incidence of intraoperative bowel injuries has been reported to be 1.78% [20] A recognized enterotomy during the operation is associated with a mortality rate of 1.7% [20]. However, if the enterotomy is not recognized during the operation the mortality rate is increased up to 7.7% [20]. Enterotomy can be repaired by laparoscopic or open approach with similar outcome result [20].

#### **6.5 Enterocutaneous fistula**

Enterocutaneous fistula after intraperitoneal non-resorbable mesh implantation was first reported in by Kaufman et al. in 1981 [21]. An overview of the current literature shows that enterocutaneous fistula after incisional hernia repair is a rare complication and occurs in up to 1% [22]. There was no association of enterocutaneous fistula if the omentum was placed between the mesh and bowel or not. In cases of enterocutaneous fistula the mesh has to be resected partially around the fistula. Complete mesh removal is very rare and depends on the surgeons experience [23]

#### **6.6 Pain**

Lomanto et al. showed that there is no difference in the amount of pain comparing laparoscopic and open hernia repair at 24 and 48 hours postoperatively [24]. However, patients undergoing laparoscopic repair had significantly less pain at 72 hours compared to open surgery allowing earlier discharge and return to work [24].

The threshold for chronic pain is set at three months postoperatively according to the International Association for the Study of Pain [25]. There is no meta-analysis investigating chronic pain after laparoscopic incisional hernia repair. Postoperative pain after mesh fixation with transfascial sutures is likely due to nerve irritation or entrapmen [26]. There is a randomized controlled trial investigating pain comparing two different techniques of mesh fixation [26]. Postoperative pain following suture fixation was significantly higher at 6 weeks postoperatively and two patients suffered from nerve irritation at sites of sutures. However, after 6 months, no difference was seen between the two groups. Pain after mesh fixation with transfascial sutures is likely due to nerve irritation or entrapment and the relatively small distance between individual sutures used in this study. The significant reduction of pain between 6 weeks and 6 months post operation in these patients could be in response to desensitisation of entrapped nerve fibres or in response to resolution of local

Laparoscopic Incisional Hernia Repair 189

On the one hand operative costs of laparoscopic incisional hernia repair compared to open surgery are significantly higher due to expensive surgical tools in laparoscopy. On the other hand in hospital costs are significantly lower in laparoscopic surgery due to shorter hospital stay, lower infection rate and less postoperative pain. However, laparoscopic incisional hernia repair is associated with significant lower overall costs. Therefore laparoscopic

Fig. 6. Intraoperative laparoscopic view of a recurrent hernia along the incision at the edge

**6.10 Costs** 

of the mesh.

incisional hernia repair is cost effective [15, 28].

inflammation [26]. Asencio et al. showed in their study that 22% of the laparoscopic group and 7% of the open group reported significantly pain three months after the operation [13]. But all were pain free one year after the operation [13] . Therefore when pain persists a surgical revisions due to nerve irritation is not recommended earlier than 6 months. Alternatively a postoperative local injection of bupivacaine and steroids or removal of the offending suture is recommended [27].

#### **6.7 Recurrence rate**

Recurrence rate is one of the most important long-term outcome parameters in laparoscopic incisional hernia repair. Forbes et al. showed in their meta-analysis no difference in the recurrence rate between laparoscopic and open incisional hernia repair [18]. The pooled recurrence rate in the laparoscopic group was 3.4% and in the open group 3.5% in this study. Such a low recurrence rate after either laparoscopic and open repair can be explained with a relatively short follow-up and the small size of the hernias [18]. A follow-up of at least three years is mandatory to evaluate correctly the real incidence of incisional hernia due to the fact that incisional hernia can occur up to 5 years after the operation. With such a long-term follow-up the incidence of recurrence has been reported to be up to 15-20% in laparoscopic and open repair [11, 13].

Two technical details can minimize the recurrence rate. First a sufficient overlap of the mesh and second the mesh fixation. We showed a significant decrease in horizontal mesh size after tack fixation (mean difference -3.1% ±3.9%) versus fixation using sutures (-0.1% ±2.3%; p=0.018) [26]. Mean vertical mesh size was not significantly different between the two groups: tack fixation -2.8% ±6.1%, suture fixation -0.7% ±4.1% (p=0.16). Mean mesh area in the tack fixation group was -12% and in the suture fixation group -2.9% at 6 months post operatively when compared to post-op day 2 (p=0.061) [26]. Therefore a sufficient meshoverlap of the hernial orifice is mandatory in order to reduce recurrence rate.

Typical locations for hernia recurrences due to the mesh shrinkage are at the margin of the mesh as shown in Fig. 6. Because the risk to gain a second incisional hernia or a recurrent hernia along the full length of the incision, it is recommended to cover the whole length of the incision during the first operation.

#### **6.8 Seroma formation**

The retained hernia sac is responsible for seroma formation. Seroma formation is classified as a complication if it lasts more than 6 weeks after the operation. A randomized controlled trial of Olmi et al. showed an incidence of seroma formation of 7% [15]. In most cases no intervention is necessary. In cases of symptoms or if the seroma lasts longer than 8 weeks a drainage is recommended. Potentially a compression dressing over a period of 7 days may prevent seroma formation.

#### **6.9 Hospitalisation time**

Forbes et al. showed in their meta-analysis that duration of hospital stay is significantly shorter in laparoscopic incisional hernia repair compared to open surgery [18]. Less amount of pain [24] and a significantly lower rate of surgical site infections in laparoscopic repair [18] are reflected in a shorter hospital stay. Influence of shorter hospital stay on overall costs in laparoscopic hernia repair is discussed below.
