Usage of a self-adhesive mesh in TAPP hernia repair: A prospective study based on Herniamed Register.

INTRODUCTION: Inguinal hernia repair is one of the most frequently performed surgical procedures worldwide in general surgery. The transabdominal laparoscopic (TAPP) approach in the therapy of inguinal hernia seems to be a suitable alternative to classical open inguinal hernia repair mainly in the hands of an experienced surgeon. TAPP repair offers the possibility of gentle dissection with implantation of the mesh and the possibility of non-invasive fixation of the implanted mesh.
MATERIALS AND METHODS: Data analysis encompassed all patients who underwent inguinal hernia surgery at our Surgical Department within the period from July 1, 2012 to September 30, 2014 and who fulfilled the inclusion criteria. The standard surgical technique was used. Data were entered and subsequently analysed on the Herniamed platform. Herniamed is an Internet-based register in German and English, and includes all data of outpatient and hospitalised patients who underwent surgery for some type of hernia. All relevant patient data are collected via Internet.
RESULTS: There were 241 patients enrolled in the group and there were 396 inguinal hernias repaired in total. Standard long-term follow-up after 12 months was evaluated in 205 patients (85.06%), and in the rest of the patients during the closing of the study, but at least 6 months after operation. The mean follow-up was at 19.69 months. At the 1-year assessment, mild discomfort was reported in the groin in 10 patients (4.88%) [1-3 on the visual analogue scale (VAS)]. Post-operative pain lasting over 12 months in the groin of moderate degree (4-6 VAS) was reported in two cases (0.97%). There was no recurrence and no chronic post-operative pain of severe degree reported.
CONCLUSION: Our study demonstrates that laparoscopic inguinal hernia repair using the TAPP technique with the implantation of a self-fixation mesh is fast, effective, reliable and economically advantageous method in experienced hands and, according to our results, reduces the occurrence of post-herniorrhaphy inguinal pain (CPIP) and has a low recurrence rate.

INTRODUCTION

Inguinal hernia repair is one of the most frequently performed surgical procedures worldwide in general surgery. There are approximately 700,000 procedures of hernia repair performed in the world every year, which results in costs of approximately USD 500,000,000 in the USA plus the costs for medication, sick leave and lost work performance. According to the German Diagnosis-Related Groups (DRG) system, the cost of surgical therapy for inguinal hernia is around 322,000,000 Euro. This means that in terms of costs, effective and reliable therapy of inguinal hernia is a significant factor that influences the efficiency of national systems of public health insurance.[37] The transabdominal laparoscopic (TAPP) approach in the therapy of inguinal hernia seems to be a suitable alternative to classical open inguinal hernia repair, mainly in the hands of an experienced surgeon.[11117] According to several studies comparing open and endoscopic/laparoscopic hernia repair, laparoscopic inguinal hernia repair is a suitable alternative primarily in case of recurrent hernias and bilateral hernias.[2345612141617] The operative technique developed by Lichtenstein that utilises the open approach and anterior positioning of the implanted mesh was considered a gold standard in inguinal hernia repairs for a long time.[15] The procedure is advantageous mainly due to its low cost, the possibility of an outpatient procedure, the use of local anaesthesia and furthermore its relatively good results, mainly with regard to the number of recurrences.[715] On the other hand, it should be noted that it is an open procedure necessitating open dissection of the groin with implantation of the mesh in the anterior position, which results in longer post-operative recovery and significantly higher incidence of pain in the groin, particularly in the first 3 months after surgery, and also leads to a higher incidence of chronic post-operative painful groin syndrome [post-herniorrhaphy inguinal pain (CPIP)].[751] Laparoscopic inguinal hernia repair offers the possibility of gentle dissection with posterior implantation of the mesh and the possibility of minimally invasive fixation of the implanted mesh.[78910]

Several prosthetic materials were introduced on the market that were intended for implantation to the groin, the safety and efficacy of which were demonstrated by several studies.[6] Originally it was necessary and recommended to stabilise the implant at the site of implantation with additional invasive fixation in a form of spirals, clips, screws, etc. These implants in inappropriate locations often were the cause of CPIP and also relatively dramatically increased the costs for that surgery.[40] This resulted in the increase of attempts to minimise the invasive fixation of an implanted mesh with the use of tissue glue, absorbable fixation materials and self-adhesive meshes.[18192021222324252627282930] The option to use self-fixation meshes in inguinal hernia repair was verified on an animal experiment as safe, well tolerated and simple to perform, with good macroscopic and microscopic integration to the abdominal wall.[31] Subsequently, self-fixation meshes that were originally intended for open implantation in inguinal hernia repairs using the Lichtenstein technique were introduced to clinical practice. Good tolerance, shortened operation time and significantly improved quality of life (QoL) were demonstrated in the questionnaires filled out by patients, while there was unchanged rate of recurrences.[22253250] Over time, several self-fixation meshes were introduced into the market that were intended for open and endoscopic implantation.[22323334] The most frequently used self-fixation meshes include the ParietexTM ProGripTM (PP) and ParietexTM ProGripTM Laparoscopic (PPL) meshes, produced by Covidien (Sofradim Production, Covidien, France). Studies on both demonstrated safety and good utility in open inguinal hernia repair.[34] For laparoscopic use, the laparoscopic version of the mesh from Covidien, the PPL, was marketed. Usage and good efficiency with unchanged recurrence rate and unchanged frequency of chronic postherrniorrhaphy inguinal pain (CPIP) were demonstrated in a retrospective study also in the case of laparoscopic TAPP inguinal hernia repair.[7] Laparoscopic inguinal hernia repair was introduced to practice in 1991 and includes the standard transumbilical approach with dissection of parietal peritoneum, treatment of hernia sac and posterior positioning of implanted material to cover the defect. The surface of the mesh is used for fixation of the mesh to the required position; after contact with tissue and combination with fine mechanical pressure, a solid connection is created, which prevents secondary shift or migration of the mesh, so that there is no need for further fixation of the mesh. In case of PP and PPL implants, the mechanism of gripping is as follows: The microgrips integrate into the tissue 0.5 mm below the lower rim and provide stronger tissue incorporation at 5 days than fixation with staples.[37] Fixation is, therefore, greatly facilitated, without requiring sutures that can penetrate underlying tissues and damage nerves.

The goal of this study, based on single-centre prospective collection of data from the Internet-based multicentre Herniamed register, is to demonstrate the safety and efficacy of the use of self-fixation meshes in standardised laparoscopic inguinal hernia repair with the TAPP technique. Although this technique of inguinal hernia repair has been in standard use in our workplace since 2008 and more than 500 patients have already been operated on, we only evaluated data from the 241 patients who were operated on at our workplace with the standardised technique, and all data were prospectively collected and stored using the Herniamed study. In total there were 396 inguinal hernias treated. All operations were performed by three surgeons with advanced experience in the field. We performed a statistical analysis of the file and evaluated all patients on the first day (D1), first month (M1) and first year (Y1) after surgery. Analysis of data was performed focusing on post-operative complications, post-operative pain, CPIP and recurrence rates. At the same time, analysis of risk factors was performed and their effect on the possible recurrence rate assessed.

MATERIALS AND METHODS

Individual inclusion and exclusion criteria are given in Table 1.

Table 1

Inclusion and exclusion criteria

Data analysis encompassed all patients who underwent inguinal hernia surgery at the Surgical Department in Bad Kissingen, Bavaria, Germany within the period from July 1, 2012 to September 30, 2014, who fulfilled the inclusion criteria. A direct control group (e.g., a group of patients operated on using TAPP technique with staple fixation of mesh) was not established, as the tested hypothesis focused on a favourable change in the QoL in patients subjected to using a self-gripping mesh, not the comparison of those methods. A standard surgical technique was used. This technique was first described by Bittner.[32] There were two surgeons with experience in this particular technique contributing on the surgeries. Because the goal of this paper was not to test any particular implant but to test the principle of self-fixation mesh application, we used self-fixation meshes available on the market. There were two types of self-fixation meshes implanted, PP and PPL. Data were entered and subsequently analysed on the Herniamed platform.

Database

Herniamed is an Internet-based multicentre register in German and English that includes all data of outpatient and hospitalised patients who have undergone surgery for some type of hernia. All relevant patient data are collected via the Internet [comorbidity, previous operation, type and size of mesh, specification of surgical procedure, used materials, peri- and post-operative complications, gender, body mass index (BMI), and risk factors in the patient].[35]

Collection of data

Surgical risk was evaluated according to the American Society of Anesthesiologists (ASA). Type of hernia, size of hernia opening, incarceration, perioperative complications, materials used, supplementary procedures and duration of surgical procedure were classified during the surgery. Complications and post-operative pain were evaluated based on the visual analogue scale (VAS) 0-10, where 0 indicates no pain, 1-3 mild pain (not evaluated as pain), 4-6 moderate pain and 7-10 severe pain. Post-operative pain was evaluated on D1 and M1 after the operation by the examination of the patient and at Y1 after the operation using an automatic questionnaire of Herniamed database. Cases with suspicion of recurrence and cases with possible CPIP were also examined clinically by the surgeon. Postoperative complications were defined as significant – major, which required prolongation of hospitalisation and less significant minor, which had no greater effect on the post-operative course in the patient. As recurrence was evaluated, ultrasound and magnetic resonance imaging (MRI) demonstrated recurrent hernia. Follow-up took place after 1 year from surgery in the form of a standardised questionnaire according to Herniamed Study.[35]

Prosthetic mesh

PP is a self-gripping composite mesh made of non-absorbable monofilament polypropylene mesh, covered with a layer of microgrips on one side. The microgrips are club-shaped 1 mm projections that are made of biodegradable monofilament polylactic acid (PLA). Polypropylene mesh has a weight of 40 g/m2 and it has 1.6 × 1.0 mm pores. The degradable component doubles the weight of the mesh to 80 g/m2. According to the manufacturer, surfaces with microgrips are fully degraded 15 months after implantation.

PPL is a self-gripping composite mesh, consistent of a monofilament polyethylene terephthalate mesh (PET), covered by a resorbable layer of microgrips made of PLA combined with segmental covering of fast resorbing film composition (70% collagen, 30% glycerol). The weight of the mesh before absorption is 82 g/m2 and weight after absorption is 49 g/m2, with the pore size (mm) 1.8 × 1.8 (macroporous). According to the manufacturer, the time for degradation of the quickly absorbing layer <1 day and that for the layer with microgrips >18 months

Operation

Anaesthesia

Standard intravenous anaesthesia with orotracheal intubation was done, which enables the Trendelenburg position. The operation was performed with a standard operating technique in the Trendelenburg position using three trocars, with the 12 mm trocar above the umbilicus and the 5 mm and 12 mm trocars at the level of the umbilicus in the left and right medioclavicular lines. Capnoperitoneum was established under a pressure of 12 mmHg and 30° optics were used. We used the technique described by Bittner.[32] After accessing the inguinal region, dissection of the parietal peritoneum on the affected side was performed at the direction from the anterior superior iliac spine up to the plica umbilicalis medialis at the same side. During dissection, gonadal vessels, vas deferens or the round ligament (in women), Cooper's ligament and the posterior fascia of the rectus abdominis muscle were visualised and prepared. After ending dissection in the groin, we introduced the prepared implant through the 12 mm trocar, which is folded (PP and PPL 15 × 9 cm). None of the meshes were not tailored. The implant was spread out in the abdominal cavity and placed to the groin in order to cover the hernia opening by at least 2-3 cm to all directions and also to cover other preformed weaker sites in the groin. Fixation to abdominal wall was accomplished by gently pressing the implant against the abdominal wall using a surgical instrument, but most effectively with a tampon. Fixation was based on a mechanical effect involving the adherence of grips to tissue (PP + PPL). The reconstruction of parietal peritoneum followed, with continuous absorbable suture. In case of a bilateral hernia, treatment is done with the same method and technique, covering both meshes in the prevesical space without the need to change the location of trocars. To reduce urethral manipulation in an effort to minimise post-operative urinary retention, patients void preoperatively and a Foley catheter is not routinely placed. No antibiotic prophylaxis is routinely administered during the surgery [Figures 1–6].

Figure 1

View of the right groin with hernia

Figure 6

Suture of parietal peritoneum

Situation after termination of dissection

Image of folded implant – PPL

Implantation of mesh

Image of mesh implanted into terminal position after fixation to the abdominal wall

RESULTS

In total, 241 patients were listed in the prospective, completely processed documentation on the Herniamed platform. In total, 396 hernias were operated on. The demographic data and preoperative data are summarised in Table 2. Perioperative data, information about the size and localisation of hernia and information about implanted materials are provided in Table 3.

Table 2

Demographic and preoperative data, n = 241

Table 3

Perioperative data and hernia details during operation

There were 241 patients enrolled in the presented group and 396 inguinal hernias were repaired. From the demographic point of view there were 218 men (90.46%) and 23 women (9.54%) out of a total of 241, with the clear dominance of 50-60 years (mean age 56.7 years ± 14.6) in males and 40-50 years (mean age 48.1 years ± 12.5) years in women. This was a heterogeneous group of patients simulating an average, non-selected group of patients undergoing inguinal hernia repair.

Representation of females in the group was around one-tenth: 23/244 (9.54%), while these were mostly bilateral hernias. Thirty-four (14.11%) of the patients were classified by the anaesthetist as ASA III. Up to 146 patients (60.58%) had had some abdominal surgery in the past. Most frequently there was a history of an open appendectomy 46 patients (19.10%).

The duration of hospitalisation varied between unilateral and bilateral disease, while the average duration of hospitalisation was 1.57 days for unilateral operation and 1.92 days for bilateral hernia. It should be noted that the duration-of-hospitalisation statistic was negatively affected by patients reoperated with acute complication, where the duration of hospitalisation was 5-8 days.

The average unilateral operation time was 66 min, while time taken for bilateral hernias was 77 min, which is not much different from other comparable published papers.[741] It should be emphasised that operating time for medial hernias is significantly shorter than for lateral hernias and also recurrent hernias, which is in accord with other authors.[7]

More than three-quarters of operated hernias, i.e., 340 hernias (85.85%) had hernia openings of moderate and large sizes (Types 2 and 3, >1.5 cm and <4 cm); lateral hernias were predominant on the left side, medial hernias on the right side.

There were two types of self-gripping meshes (PP and PPL), without planned selection; PP were most frequently implanted [235 (58.59%)], then PPL [164 (41.41%)] meshes.

During the surgery, no complications were demonstrated; post-operative complications were evaluated as significant in relation to previous surgical procedures (major) and as less significant (minor), which did not influence the duration of hospitalisation, and these were managed conservatively on an outpatient basis.

In the summary of major complications in Table 4, postoperative bleeding predominates, in one case from; in this case it was a patient with a history of insufficiently compensated anti-coagulation therapy. There was one case of trocar side bleeding. One patient developed post-operative ileus, caused by incarceration of the small bowel loop in a loose suture of parietal peritoneum. All cases were treated with the laparoscopic technique; there was no need of bowel resection or mesh explantation.

Table 4

Complications

Long-term follow-up, recurrence and chronic pain evaluation are summarised as follows. Standard long-term follow-up after 12 months was done in 205 patients (85.06%); in the rest of the patients it was performed during the closing of the study, although at least 6 months after operation. The mean follow-up was at 19.69 months. Long-term follow-up was performed with the standard questionnaire based on the Herniamed platform. There were questions regarding post-operative complications, post-operative pain longer than 3 months according to the VAS, type of pain (resting, during movements), need of medicamentous therapy and, possibly, recurrence or reoperation. At the 1-year assessment, mild discomfort was reported in the groin in 10 patients (4.88%), which it had no effect on any patient's usual activity and did not require any therapy (1-3 VAS). Post-operative pain of moderate degree (4-6 VAS) lasting over 3 months in the groin was reported in three cases (1.46%). After 1 year the number of patients declined to two (0.97%). Pain analysis with the use of VAS scores is given in Table 5, and pain in Table 6. No chronic post-operative pain of severe degree was reported. In two of three patients, pain persisted at the same intensity for more than 12 months. There was no recurrence of inguinal hernia confirmed in the followed-up group. We reported only one suspected recurrence, which was shown on MRI examination to be a pseudorecurrence, while there was persisting lipoma in the left groin with satisfactory positioning of the mesh and no sign of recurrence. A summary is given in Table 7.

Table 5

Patient-reported pain using VAS scale prior to surgery and each to follow-up evaluation

Table 6

Recurrence rate and chronic pain

Table 7

Analysis of chronic pain after Y1, n = 205

DISCUSSION

Laparoscopic inguinal hernia repair became one of the standard methods to treat inguinal hernia, mainly in cases of recurrent hernias, bilateral hernia and femoral hernia.[2111641] More than 70 different studies and meta-analyses comparing laparoscopic endoscopic and open inguinal hernia repairs stated comparable long-term results focusing on the recurrences, post-operative pain and QoL of patients.[234513] Mild differences were reported in the occurrence of chronic post-operative pain.[23839] Although there were studies that reported a higher recurrence rate in laparoscopic repairs than in inguinal hernia repairs, it may be more a question of the experience of the operating surgeon than of a real failure of surgical technique.[7] One of the remaining problems in the field of laparoscopic inguinal hernia repair is the problem of fixation or non-fixation of prosthetic material. It has been shown that traumatic fixation of the mesh increases the possibility for the development of CPIP.[4647] This is why atraumatic fixation of prosthetic material is recommended.[84647] For example, in case of endoscopic totally extraperitoneal (TEP) technique, it has been shown that it is possible to withdraw from traumatic fixation of the implant without increasing the risk of recurrence.[21242] In the case of laparoscopic inguinal hernia repairs, the efficiency of the so-called non-traumatic fixation of the implant, e.g., with tissue glue was shown, without an increased recurrence rate.[48] An alternative to atraumatic fixation with tissue glue is the use of the so-called self-fixation mesh, which enables sufficient implant fixation to the abdominal wall, provided by a specially adjusted surface without the need of additional fixation.[1742] Birk et al. presented the first larger, retrospective study focusing on the use of the PP implant, with great results in terms of CPIP and recurrence rate.[7]

Intraoperatively we have not seen any injury or relevant complication. Post-operative complications, which we recorded, included mainly extraperitoneal haematoma in the groin in one patient, associated with insufficiently compensated chronic anticoagulation therapy. One haemorrhage at the trocar side was also reported. All cases were treated with laparoscopy, and there was no need to remove the implant. We recorded some post-operative complication in 8 patients (3.32%) in our study, while only three patients (1.20%) developed more significant complications. This is completely in accord with other authors.[78415253] The authors of the publication evaluated previous, insufficiently compensated anticoagulation therapy as a risk factor. The authors considered any previous abdominal surgery, mainly infra-umbilical surgery, which significantly prolongs duration of surgery, as a partial risk factor.

The primary goal of successful inguinal hernia repair is reconstruction of the groin without recurrence and without development of chronic CPIP or reduced QoL.

Pain

It has been demonstrated that the use of VAS for the quantification of post-operative pain is simple and satisfactory in hernia surgery.[95455] There have been more than 20 studies published that focused on the evaluation of chronic post-operative pain and CPIP in laparoscopic inguinal hernia repair, which all confirm low incidence of chronic pain and discomfort in the groin after laparoscopic TAPP.[495658] In our study, we reported chronic pain lasting more than 3 months in three patients. In one case it was bilateral pain after bilateral repair, which subsided after conservative therapy within Y1 after operation and in the Y1 follow-up was not demonstrated anymore. In two other patients with unilateral chronic pain, it was possible to reduce pain so much that it did not require any surgical therapy. The relatively favourable result of CPIP occurring in only 0.97% of patients is promising but generally in accord with other authors.[74956] Mild discomfort in the groin, that could not be evaluated as pain, was reported in 4.88% of patients. It was not limiting in daily life and did not require any therapy. Surprisingly, there was no post-operative pain reported even on D1 (VAS = 0) in 20 patients (8.29%). Also interesting is the relationship of preoperative and post-operative pain, when preoperative pain developed as a negative predictive factor of post-operative pain. This fact confirms the work of Aasvang et al. who in one paper defined the negative predictive factors of chronic post-operative pain.[57]

Recurrence

There was only one suspicion of recurrent hernia, which was not confirmed by MRI. The patient did not report any pain or greater discomfort up to the date of examination.

Prosthetic material

In this study, the PP and PPL implants were used. We identified one study that confirmed effective use of a self-adhesive mesh: AdhesixTM produced by Bard (Cousin Biotech, Bard Davol) in clinical practice in open inguinal hernia repair.[60] Gruber-Blum et al. compared the self-fixation meshes PP and AdhesixTM in an animal study, and showed better results and greater stability for the PP implant, due to the longer effect of adherence provided by its minigrips, which degraded for several months.[3659] We could not validate this finding because of lack of experience with this type of mesh.

A frequently reported post-operative complication of TAPP inguinal hernia repair is seroma. It was documented only 2× (0.5%) in our group, which is attributed to the consequent suture of the hernia opening with fixation of transversal fascia in direct inguinal hernias in those cases.

In our file, we reported no wound infection or mesh infection. Prophylactic administration of antibiotics was demonstrated as unjustified apart from cases with clear increased risks.[57] As we routinely administered antibiotic prophylaxis until 2013 using cephazolin 2 g as a single dose, the percentage of prophylactic administration of antibiotics exceeds 90%. In the last year we stopped general administration of antibiotic prophylaxis without any increased risk of complications.

Several studies demonstrated that non-fixation inguinal hernia repair is generally more cost-effective than fixating inguinal hernia repair.[434445]

The goal of our study was not to analyse the costs, but it is logical that in spite of the slightly higher price of the self-fixation implant, the total cost for the implant and the fixation medium is significantly higher. It may be argued that the costs for open inguinal hernia repair are significantly lower, mainly based on the costs for laparoscopic instrumentation and equipment. However, making this comparison was not the goal of the work. While respecting the current knowledge and certainly the shorter recovery time, better QoL and lower frequency of CPIP, and perhaps also the lower recurrence rate, the use of laparoscopic/endoscopic inguinal hernia repair is preferable also with obviously higher material costs.[7]

CONCLUSION

According to our experience, considering that this technique of inguinal hernia repair with the self-fixation mesh has been in standard use since 2008 and that more than 500 patients have undergone the operation, it is a suitable and effective alternative for all laparoscopic surgeons. The legitimacy of the use of the self-fixation mesh was demonstrated in an experiment,[31] in open inguinal hernia repair,[3250] in TEP[42] and in TAPP technique.[741] Our study as well as long-term experience with the self-fixation mesh demonstrates that laparoscopic inguinal hernia repair using the TAPP technique with implantation of a self-fixation mesh is fast, effective, reliable and economically advantageous method in experienced hands, which combines the advantages of laparoscopic approach with simple and practical implantation of self-fixation mesh, which according to our results reduces the occurrence of CPIP and the recurrence rate. Based on the submitted study it is possible to recommend the technique mentioned above to the surgeons experienced in laparoscopic TAPP (probably also TEP) of inguinal hernia repair with the use of a self-fixation mesh as an advantageous, and possibly in future also standard, combination of surgical technique and an implant.

Financial Support and Sponsorship

Nil.

Conflicts of Interest

There are no conflicts of interest.