Adhesion formation in laparoscopic inguinal hernia repair

Background: In laparoscopic inguinal hernia repair controversy exists concerning the most appropriate repair method and implant material to use if intraabdominal adhesions are to be minimized. Methods. In 108 pigs, we implanted three different types of mesh by both the TAPP (transabdominal preperitoneal) and Onlay (prosthesis placed directly upon the peritoneum) methods. Specimens were harvested in three time periods and adhesion formation was compared. Results. Average adhesions at 3 days were TAPP 18% and Onlay 49% (p < 0.001). At 3 weeks average adhesions were TAPP 8% and Onlay 23% (p < 0.04). Three-month figures were TAPP 1% and Onlay 13% (p < 0.001). In contrast, there were no differences in adhesion formation due to material type in any of the three time periods (all p > 0.17). Conclusions: A peritoneal covering over a laparoscopic inguinal implant significantly reduced adhesions. Prosthetic material type did not affect adhesion formation in this study.     

Adhesion formation is reduced after laparoscopic surgery

Background: Adhesion formation after abdominal operations causes significant morbidity. Methods: Adhesion formation in pigs was compared after placement of prosthetic mesh during celiotomy (group 1), laparoscopy with large incision (group 2), and laparoscopy (group 3). After peritoneum was excised, polypropylene mesh was fixed to the abdominal wall, then to the opposite abdominal wall in the preperitoneal space followed by peritoneal closure. Adhesion area, grade, and vascularity were measured. Results: More adhesions (p < 0.02) covered intraperitoneal mesh (7.57 ± 1.89 cm²) than covered reperitonealized mesh (2.16 ± 1.13 cm²), and adhesion grade was significantly greater (p < 0.02). Adhesion areas were significantly greater in groups 1 and 2 than in group 3 (p= 0.001 and 0.03, respectively). Adhesion grade was significantly greater in groups 1 and 2 than in group 3 (p= 0.02 and p= 0.04, respectively). Groups 1 and 2 had more vascular adhesions than group 3 (p < 0.01 and p= 0.02, respectively) Conclusions: A foreign body within the peritoneum stimulates more numerous and denser adhesions. Tissue trauma distant from the site of adhesions increases their formation. A major advantage of laparoscopic surgery is decreased adhesion formation. Received: 23 January 1998/Accepted: 10 March 1998     

Prevention of adhesion formation to polypropylene mesh by collagen coating: A randomized controlled study in a rat model of ventral hernia repair

Introduction In laparoscopic incisional hernia repair with intraperitoneal mesh, concern exists about the development of adhesions between bowel and mesh, predisposing to intestinal obstruction and enterocutaneous fistulas. The aim of this study was to assess whether the addition of a collagen coating on the visceral side of a polypropylene mesh can prevent adhesion formation to the mesh.Method In 58 rats, a defect in the muscular abdominal wall was created, and a mesh was fixed intraperitoneally to cover the defect. Rats were divided in two groups; polypropylene mesh (control group) and polypropylene mesh with collagen coating (Parieten mesh). Seven and 30 days postoperatively, adhesions and amount and strength of mesh incorporation were assessed. Wound healing was studied by microscopy.Results With Parieten mesh, the mesh surface covered by adhesions was reduced after 30 days (42% vs 69%, p = 0.01), but infection rate was increased after both 7 (p = 0.001) and 30 days (p = 0.03), compared to the polypropylene group with no mesh infections. If animals with mesh infection were excluded in the analysis, the mesh surface covered by adhesions was reduced after 7 days (21% vs 76%, p = 0.02), as well as after 30 days (21 vs 69%, p < 0.001). Percentage of mesh incorporation was comparable in both groups. Mean tensile strength of mesh incorporation after 30 days was higher with Parieten mesh.Conclusion Although the coated Parieten mesh was more susceptible to mesh infection in the current model, a significant reduction of adhesion formation was still seen with the Parieten mesh after 30 days, with comparable mesh incorporation in the abdominal wall.     

Transabdominal Preperitoneal Herniorrhaphy using Laser-Assisted Tissue Soldering in a Porcine Model

Background and Objectives:

Collagen solder is capable of fixation of surgical meshes during laparoscopic herniorrhaphy without compromising tissue integration, increasing adhesions or inflammation. This pilot study describes development of instrumentation and techniques for transabdominal preperitoneal (TAPP) herniorrhaphy using laser-assisted soldering technology.

Methods:

Anesthetized 20-kg to 25-kg female Yorkshire pigs underwent laparoscopy performed using a 3-trocar technique. Peritoneal incisions were made and pockets created in the preperitoneal space for mesh placement. Parietex TEC mesh segments embedded in 60% collagen-solder were soldered to the muscle surface by using a prototype laser (1.45µ, 4.5W CW, 5mm spot, and 55°C set temperature) and custom laparoscopic handpiece. Parietex TEC mesh segments (Control) were affixed to the muscle with fibrin sealant (Tisseel). Peritoneal closure was with staples (Control) or by soldering collagen embedded Vicryl mesh segments over the peritoneal incision (Mesh/TAPP). Segments were inserted using a specially designed introducer. Animals were recovered and underwent second-look laparoscopy at 6 weeks postimplantation. Mesh sites were harvested after animals were euthanized.

Results:

The mesh-solder constructs were easily inserted and affixed in the TAPP approach. Tisseel tended to drip during application, particularly in vertical and ventral locations. Postoperative healing was similar to Control segments in all cases. Mesh/TAPP closures healed without scarring or adhesion formation.

Discussion and Conclusion:

Collagen-based tissue soldering permits normal wound healing and may mitigate or reduce use of staples for laparoscopic mesh fixation and peritoneal closure. Laser-assisted mesh fixation and peritoneal closure is a promising alternative for laparoscopic herniorrhaphy. Further development of this strategy is warranted.     

Laparoscopic intraabdominal hernioplasty as the operation of choice in the inguinal hernia treatment

Comparative analysis of a pain syndrome severity was done, using a visual analogous scale (VAS), basing on the analysis of performance of various kinds of laparoscopic prosthesis inserting hernioplasty for inguinal hernia, using intraabdominal (intraperitoneal onlay mesh - IPOM) and preperitoneal (transabdominal preperitoneal - TAPP) with establishment of light nets. A pain severity is trustworthy lesser in the IPOM method application--5 and 17.5 points, accordingly. The operation duration, using IPOM, have had constituted (60 +/- 20) min at average and while using TAPP--(113 +/- 42) min. The stationary postoperative state duration after the IPOM procedure was a twice lesser--1.12 and 2.8 days, accordingly. Laparoscopic prosthesis inserting intraabdominal hernioplasty, according to the IPOM method, may constitute the operation of choice, performed for inguinal hernia.     

Cine magnetic resonance imaging vs high-resolution ultrasonography for detection of adhesions after laparoscopic and open incisional hernia repair: a matched pair pilot analysis

Background Intraabdominal adhesions represent nonspecific complications before or after laparoscopic or open incisional hernia repair. The objective of this matched control pilot study was to display long-term adhesions noninvasively by applying functional cine magnetic resonance (MR) imaging, as compared with applying high-resolution ultrasonography (US). Methods The study group, composed of 17 consecutive patients (12 men and 5 women; mean age, 52 years), underwent laparoscopic intraperitoneal onlay mesh repair using expanded polytetrafluoroethylene (ePTFE) mesh. Their mean body mass index was 30 kg/m², and the size of the hernia was 95 cm². Another group, matched for age, gender, and type of hernia, was subjected to open abdominal wall repair using the preperitoneal sublay technique with a large-pore, low-weight polypropylene mesh. For cine MR imaging (1.5 T), section-by-section dynamic depiction of induced visceral slide throughout the entire abdomen was achieved by applying transverse or sagittal true fast imaging with steady-state precession sequences. The location and type of adhesions were compared with high-resolution ultrasonography using nine segments of the abdominal map. Results The patients subjected to laparoscopic and open incisional hernia repair were examined 16 and 28 months after surgery. The findings showed functional cine MR imaging as superior to high-resolution ultrasonography for assessing the amount of intraabdominal adhesions (n = 53 vs n = 3; p < 0.01). Most frequently, adhesions were seen between small bowel loops and the abdominal wall (n = 22), followed by bowel-to-bowel adhesions (n = 19; p < 0.05). However, adhesions between small bowel loops and the abdominal wall occurred more frequently after open mesh repair (p < 0.05). Furthermore, a strong correlation was observed between patient complaints and findings with cine MR imaging (p < 0.05). Maximum pain correlated significantly with the region of the most distinctive adhesions (p < 0.05). Conclusions Functional cine MR imaging represents a reliable noninvasive technique for detecting long-term adhesions after open and laparoscopic incisional hernia repair. The study results suggest that this approach has distinct advantages over high-resolution ultrasonography.     

Small bowel lesion due to spiral tacks after laparoscopic intraperitoneal onlay mesh repair for incisional hernia

INTRODUCTIONLaparoscopic intraperitoneal onlay mesh (IPOM) repair has become a widely accepted operative technique for incisional hernias. However, tack fixation poses the risk of adhesions and injury to the intestine. We report the case of spiral tacks adherent to the small bowel after IPOM repair for incisional hernia.PRESENTATION OF CASE64 years old male patient who underwent laparoscopic IPOM repair for incisional hernia 1 year after open sigmoid resection. A laminated polypropylene mesh was fixed with titanium spiral tacks. 4 years later, elective open cholecystectomy was performed. Two spiral tacks integrated in the seromusular layer of the small bowel were encountered. Tacks were removed and bowel lesions oversewn with interrupted seromuscular stitches.DISCUSSIONAccording to the current literature, complications related to metal spiral tacks in IPOM mesh repair such as intestinal perforation or strangulation ileus seem to be rare. To our knowledge, spiral tacks adherent to the intestine have not yet been published to date. Alternative techniques for mesh fixation are transfascial sutures with single stitches, continuous sutures or fibrin glue, as already used in TAPP and TEP procedures for inguinal hernia repair. The ideal and safest technique for mesh fixation in IPOM repair for incisional hernias remains controversial.CONCLUSIONSpiral tacks used for intraperitoneal mesh fixation can lead to adhesions and bowel lesions. Sutures, absorbable tacks or fibrin glue are alternatives for mesh fixation. Further clinical trials are needed to evaluate the safest technique of laparoscopic IPOM incisional hernia repair.     

Open or laparoscopic preperitoneal mesh repair for recurrent inguinal hernia?

Background: Giant prosthetic reinforcement of the visceral sac (GPRVS), an open preperitoneal mesh repair, is a very effective groin hernia repair. Laparoscopic transabdominal preperitoneal repair (TAPP), based on the same principle, is expected to combine low recurrence rates with minimal postoperation morbidity. Methods: Seventy-nine patients with 93 recurrent and 15 concomitant primary inguinal hernias were randomized between GPRVS (37 patients) and TAPP (42 patients). Operating time, complications, pain, analgesia use, disability period, and recurrences were recorded. Results: Mean operating time was 56 min with GPRVS versus 79 min with TAPP (p < 0.001). Most complications were minor, except for a pulmonary embolus and an ileus, both after GPRVS. Patients experienced less pain after a laparoscopic repair. Average disability period was 23 days with GPRVS versus 13 days with TAPP (p= 0.03) for work, and 29 versus 21 days, respectively (p= 0.07) for physical activities. Recurrence rates at a mean follow-up of 34 months were 1 in 52 (1.9%) for GPRVS versus 7 in 56 (12.5%) for TAPP (p= 0.04). Hospital costs in U.S. dollars were comparable, with GPRVS at $1,150 and TAPP at $1,179. Conclusions: Laparoscopic repair of recurrent inguinal hernia has a lower morbidity than GPRVS. However, laparoscopic repair is a difficult operation, and the potential technical failure rate is higher. With regard to recurrence rates, the open preperitoneal prosthetic mesh repair remains the best repair. Received: 14 April 1998/Accepted: 28 May 1998     

Omentum prevents intestinal adhesions to mesh graft in abdominal infections and serosal defects

Background Many studies have evaluated the use of grafts in the reconstruction of abdominal wall defects. In this study, the effects resulting from the presence or absence of the omentum were evaluated in the setting of infection or serosal defects in the formation of adhesions in abdominal closures using mesh grafts. Methods For this study, 60 Wistar albino rats were divided into six groups. A circular 3.79-cm² fascioperitoneal defect was created. After group-specific procedures, defects were reconstructed using polypropylene mesh grafts. In group C (control group), only a mesh graft recontruction was performed, whereas group O (O for omentectomy) underwent an omentectomy plus mesh closure. In group SD (serosal defect group), the cecum was abrased with a brush before mesh closure. Group SDO underwent cecal abrasion plus an omentectomy. In group I (infection group), the intraabdominal space was filled with 1 ml of solution containing 100,000 colony-forming units (CFUs) of Escherichia coli per milliliter. Group IO received the same same amount of E. coli solution plus an omentectomy before mesh closure. After 28 days, the groups were evaluated by intraabdominal and blood cultures, grading of intraabdominal adhesions, graft–organ adhesions, proportion of adhesions to graft size, and histopathologic studies. The results were statistically evaluated using one-way variant analysis and Scheffe’s and Fisher’s definite chi-square tests. Results For the groups in which the greater omentum was preserved, intestinal adhesions to the graft surface were less frequently observed, especially in cases with intraabdominal infections and serosal defects (p < 0.05). Conclusions Preservation of the greater omentum reduces the formation of intestinal adhesions, especially in cases with underlying infections and serosal defects in abdominal closures using mesh grafts. This could be beneficial in related clinical situations in lowering the rate of intestinal fistulas, erosions, and obstructions that can be attributed to the formation of adhesions.     

Laparoscopic inguinal herniorrhaphy. Results of a multicenter trial.

OBJECTIVE: The purpose of this study was to determine if laparoscopic inguinal herniorrhaphy represents a viable alternative to the conventional repair and to assess whether a prospective randomized controlled trial comparing both procedures is warranted. METHODS: Three types of laparoscopic inguinal herniorrhaphies (transabdominal preperitoneal [TAPP], intraperitoneal onlay mesh [IPOM], and totally extraperitoneal [EXTRA]) were studied in a phase II design. Twenty-one investigators from 19 institutions participated. Approval from the local human research committee was required at each institution before patients could be enrolled. RESULTS: There were 686 patients with 869 hernias; 366 (42.1%) were direct, 414 (47.6%) were indirect, 22 (2.5%) were femoral, and 67 (7.7%) were combination hernias. The TAPP procedure was used for 562 hernias, the IPOM was used for 217 hernias, and the EXTRA was used for 87 hernias. Sixty-one patients had additional abdominal procedures performed at the time of laparoscopy without any adverse affects on their herniorrhaphies. The overall recurrence rate was 4.5%, with a minimum follow-up of 15 months. Complications were divided into the following three groups: 1) those related to laparoscopy, 2) those related to the patient, and 3) those related to the herniorrhaphy. Complications related to the laparoscopy occurred in 5.4% of patients; bleeding or abdominal wall hematomas occurred 31 times, (two patients required transfusion); one patient had bowel perforation, which was sutured laparoscopically; a bladder injury required laparotomy for management. Patient complications occurred in 6.7%. The majority involved the urinary tract (5.8%). Two patients required secondary abdominal procedures for adhesions, one for pain in the right lower quadrant and the other for adhesive small bowel obstruction. Postoperative myocardial infarction on day 5 resulted in the only operative mortality, for a rate of 0.1%. Complications related to the herniorrhaphy itself occurred in 17.1%. Most of these were minor, consisting of transient groin pain (3.5%), seroma (3.5%), transient leg pain (3.3%), hematoma (1.5%), or transient cord or testicular problems (0.9%). The incidence of leg pain decreased dramatically as surgeons became more familiar with the anatomy of the nerve supply to the groin when viewed laparoscopically. Ninety-three percent of patients were discharged within 24 hours of their operations. CONCLUSIONS: Laparoscopic inguinal herniorrhaphy is an effective method to correct an inguinal hernia. It can be offered safely to patients undergoing other abdominal procedures. The TAPP, IPOM, and EXTRA procedures appear to be equally effective. A controlled randomized trial is needed to compare this procedure with conventional inguinal herniorrhaphy.     

In vivo study of meshes implanted over the inguinal ring and external iliac vessels in uncastrated pigs

Background: The effects of placing a prosthesis directly on the internal inguinal ring and external iliac vessels in inguinal hernia repair are unknown. We compared tissue responses to five prostheses implanted in this position in uncastrated male pigs. Methods: Three types of polypropylene and two types of expanded polytetrafluoroethylene (ePTFE) mesh were implanted in 20 pigs (n= 8 for each prosthesis type). Specimens of the implants and surrounding tissue were obtained 30 and 90 days after implantation and assessed histologically. Results: The polypropylene implants had more adhesions, more surface area covered by adhesions, and more tenacious adhesions than did the ePTFE implants. Perivascular cuffing was observed in eight polypropylene and one ePTFE specimen; ossification, necrosis, and testicular venous congestion were seen in polypropylene specimens. Conclusions: Abnormal healing processes after implantation of polypropylene mesh may increase complications of the transabdominal preperitoneal and total extraperitoneal approaches in laparoscopic inguinal hernia repair, whereas the minimal response to ePTFE meshes may make them safer for use in the preperitoneal space. Received: 2 April 1997/Accepted: 8 August 1997     

Totally extrafasdal endoscopie preperitoneal hernia repair: a merger of anatomy and surgery. The exact description to endoscopkally dissect the spermatic fascia

Summary  Stoppa introduced giant preperitoneal mesh repair after parietalisation of the cord in inguinal hernias. Based on this principle, a preperitoneal mesh is inserted during the laparoscopic transabdominal preperitoneal (TAPP) repair. Central to the Stoppa operation is identification of the bloodless plane between peritoneum and urogenital fascia. Dissection of this plane has not been described for the TAPP hernia repair. We present a reproducible, anatomicallybased method of finding and dissecting the urogenital fascia in the TAPP. Methods: After routine peritoneal incision, the urogenital fascia is identified late-rally in the Bogros space, where it is loosely adherent to the peritoneum. Here, developing the cleavage plane between the fascia and peritoneum is easy. The dissection is extended medially into the space of Retzius. Once the medial and lateral planes have been dissected, reducing the hernia sac is uncomplicated and bloodless. Because the urogenital fascia continues around the cord structures as the spermatic sheath, there is no danger of damaging these and it is easy to parietalise the vas deferens and testicular vessels. The mesh is then inserted true to the original dictates of Stoppa. Discussion: The precise preperitoneal dissection plane has not been elucidated for laparoscopy. The fascial anatomy in the groin is a complex arrangement between peritoneum, urogenital fascia and transversalis fascia. Dissection between the correct fascial layers allows rapid identification of the exact anatomy in an avascular plane. This ensures true parietalisation of the cord structures in an ordered and anatomically correct fashion.     

Comparison of Adhesive Properties of Five Different Prosthetic Materials Used in Hernioplasty

This experimental study was designed to assess and to compare intra-abdominal adhesions following the use of five commercially available prosthetic mesh grafts in the repair if abdominal wall defects. Sixty Wistar albino rats were randomly divided into six groups (n = 10). A 2 × 1 cm defect at abdominal wall was created and defects were closed either primarily or with one of the following prosthetic mesh grafts: monofilament polypropylene, polytetrafluoroethylene, sodium hyaluronate/carboxymethylcellulose-coated polypropylene, polypropylene/polyglactin 910 composite, or resorbable hydrophilic collagen-coated multifiber polyester. The severity of adhesions was graded, tensile strengths of adhesions were measured, and histopathological grades of inflammation and fibrosis were evaluated. Polypropylene mesh resulted in more adhesion formation in comparison to primary repair and other grafts used in this study, except polypropylene/polyglactin 910 composite mesh. In addition, the highest tensile strength of omental adhesions was detected in the polypropylene group (χ² = 26.249; p =. 0001). Polyester composite mesh caused the least adhesion formation among the groups. Sodium hyaluronate/carboxymethylcellulose-coated polypropylene and polyester composite meshes revealed the highest fibrosis scores (χ² = 50.776; p =. 0001). The highest inflammatory activity was detected in the polytetrafluoroethylene mesh group (χ² = 16.564; p =. 005). Thus, sodium hyaluronate/carboxymethylcellulose-coated polypropylene and polytetrafluoroethylene meshes following polyester composite mesh were the minimal adhesion-forming grafts in this study. Disadvantages of the polytetrafluoroethylene mesh were lower fibrotic activity and higher inflammatory reaction to the graft.     

Open intraperitoneal hernia repair for treatment of abdominal wall defects--early results by placement of a polypropylene-ePTFE-mesh

BACKGROUND: Large incisional hernias are mainly repaired today by tension free implantations of prosthetic meshes using various placement methods. The advantages of the intraperitoneal open technique (IPOM) using a polypropylene mesh that is coated with ePTFE on the side facing the intestine, are described. METHODS AND RESULTS: 62 patients underwent an incisional hernia operation with the intraperitoneal positioning of a prosthetic mesh. The follow-up examinations after a range of 16.1 months showed a hernial recurrence rate of 6.4 %. A part of the resulting mesh infections (11.2 %) healed without surgical removal of the mesh. Clinical complications due to adhesion formation were not observed. CONCLUSION: The tissue sparing intraabdominal positioning technique simplifies the necessary overlap using healthy tissue as a prerequisite for a sufficient hernia repair exploiting the intraabdominal pressure.     

Five-year outcome of laparoscopic and Lichtenstein hernioplasties

Background: Laparoscopic hernia repair has been proved superior to open repairs in terms of short-term results, but long-term results of laparoscopic and open mesh repairs have been lacking until recently. Methods: A total of 123 patients were randomly allocated to two treatment groups comparing laparoscopic and Lichtenstein hernioplasties in three separate trials. The first and second trials compared small and large mesh used in transabdominal preperitoneal repairs, and the third study compared totally extraperitoneal hernioplasty with the Lichtenstein operation. A 5-year follow-up visit was scheduled to assess recurrencies, symptoms, and patient satisfaction. Results: For the follow up evaluation, 121 (98.4%) of the patients were reached. There were five hernia recurrences in the laparoscopic group (small mesh) and two in the Lichtenstein group (difference, 5%; 95% confidence interval, –4–13%; p = 0.3). One patient who underwent the transabdominal preperitoneal polypropylene procedure underwent reoperation 3 years later because of dense small bowel adhesions at the inguinal surgical site. Chronic groin pain was more common after open operation (0 vs 4) patients (difference 7%; confidence interval, –0.4–16%; p = 0.04). Ten patients (16%) in the laparoscopic group and 12 (20%) in the open group reported discomfort or pain at the surgical site. Conclusions: Both laparoscopic and Lichtenstein hernioplasties have a low risk for hernia recurrence if proper mesh size is used. The patients who undergo hernioplasty with open mesh hernioplasty seem to experience chronic symptoms and pain more often than those managed with the laparoscopic procedure.     

Assessment of adhesion formation to intra-abdominal polypropylene mesh and polytetrafluoroethylene mesh

BACKGROUND: The development of intra-abdominal adhesions, bowel obstruction, and enterocutaneous fistulas are potentially severe complications related to the intraperitoneal placement of prosthetic biomaterials. The purpose of this study was to determine the natural history of adhesion formation to polypropylene mesh and two types of polytetrafluoroethylene (ePTFE) mesh when placed intraperitoneally in a rabbit model that simulates laparoscopic ventral hernia repair. MATERIALS AND METHODS: Thirty New Zealand white rabbits were used for this study. A 10-cm midline incision was performed for intra-abdominal access and a 2 cm x 2 cm piece of mesh (n = 60) was sewn to an intact peritoneum on each side of the midline. Two types of ePTFE mesh (Dual Mesh and modified Dual Mesh, W.L. Gore & Assoc., Flagstaff, AZ) and polypropylene mesh were compared. The rate of adhesion formation was evaluated by direct visualization using microlaparoscopy (2-mm endoscope/trocar) at 7 days, 3 weeks, 9 weeks, and 16 weeks after mesh implantation. Adhesions to the prosthetic mesh were scored for extent (%) using the Modified Diamond Scale (0 = 0%, 1 50%). At necropsy the mesh was excised en bloc with the anterior abdominal wall for histological evaluation of mesothelial layer growth. RESULTS: The mean adhesion score for the polypropylene mesh was significantly greater (P < 0.05) than Dual Mesh at 9 weeks and 16 weeks and modified Dual Mesh at 7 days, 9 weeks, and 16 weeks. Fifty-five percent (n = 11) of the polypropylene mesh had adhesions to small intestine or omentum at necropsy compared to 30% (n = 6) of the Dual Mesh and 20% (n = 4) of the modified Dual Mesh. There was a significantly greater percentage (P < 0.003) of ePTFE mesh mesothelialized at explant (modified Dual Mesh 44.2%; Dual Mesh 55.8%) compared to the polypropylene mesh (12.9%). CONCLUSIONS: Serial microlaparoscopic evaluation of intraperitoneally implanted polypropylene mesh and ePTFE mesh in a rabbit model revealed a progression of adhesions to polypropylene mesh over a 16 week period. The pore size of mesh is critical in the development and maintenance of abdominal adhesions and tissue ingrowth. The macroporous polypropylene mesh promoted adhesion formation, while the microporous nature of the visceral side of the ePTFE served as a barrier to adhesions.     

Prospective randomized trial of laparoscopic (transabdominal preperitoneal) vs open (mesh) repair for bilateral and recurrent inguinal hernia

Background: Laparoscopic hernia repair excites controversy because its benefits are debatable and critics claim it is attended by serious complications. The one group of patients in whom benefits may outweigh the perceived disadvantages are those with bilateral or recurrent inguinal hernias. Method: One hundred twenty patients with bilateral or recurrent hernias were randomized to either laparoscopic transabdominal preperitoneal (TAPP) or open mesh repair. Patients completed a well-being questionnaire prior to and following surgery together with a visual analog pain score. Patients were followed up clinically at 1 and 3 months and thereafter by their general practitioner. Results: Age and sex distribution was similar in the two groups. Laparoscopic TAPP hernia was quicker (40 vs 55 min; p < 0.001), less painful (visual analog pain score, 2.8 vs 4.3; p = 0.003) and allowed earlier return to work (11 vs 42 days; p < 0.001) compared to open mesh repair. Conclusion: This trial demonstrates that laparoscopic hernia repair via the TAPP route offers significant benefit to patients undergoing bilateral or recurrent inguinal hernia repair.     

A prospective cost and outcome comparison of inguinal hernia repairs

We previously showed that patients undergoing transabdominal preperitoneal laparoscopic inguinal herniorrhaphy (TAPP) returned to activity twice as fast as open herniorrhaphy without mesh but that TAPP was twice as expensive. However, it was not clear if the immediate postoperative benefits offered by TAPP resulted from smaller incisions and less tissue dissection or from the requisite tension-free placement of mesh. We have therefore completed a prospective outcome and cost analysis comparing TAPP (n=59) to open preperitoneal mesh herniorrhaphy (PPO) (n=40) to determine the differences between the two different surgical techniques. When comparing unilateral repairs, there was no difference in hernia type. PPO patients were older (P<0.05) and their operations were shorter (P<0.01). Comparison of outcome parameters of pill days, out-of-house activity, and intial day to full activity revealed no difference. Cost analysis showed that total costs, disposable equipment costs, and operating room time costs were significantly less for PPO (P<0.01). There were two major complications (3%) and twelve minor complications (20%) in the TAPP group while PPO exhibited no major and five minor complications (12%). Follow-up data revealed one recurrence in the TAPP group. There were no recurrences in the PPO group at only 7 months average follow-up. We conclude that since both procedures had similar outcomes in the immediate postoperative period, the increased cost of TAPP and increased potential for both major and minor complications make it difficult to justify its routine use.Presented at the annual meeting of the Society of American Gastrointestinal Endoscopic Surgeons (SAGES), Orlando, Florida, USA, 11–14 March 1995     

Comparison of biomaterials: three meshes and TAPP for inguinal hernia

Background In laparoscopic hernia repair the use of biocompatible materials is necessary. A prospective, double-blind study was projected to compare three different meshes. Methods Ninety male patients with primary inguinal hernia undergoing transabdominal preperitoneal (TAPP) implant procedures were included. Three different types of mesh were tested: a monofile, heavy-weight, rigid mesh (group A), a smooth, heavy-weight variant of polypropylene (group B), and a polyglactin/polypropylene compound mesh (group C). Complications, pain development, inability to work, physical conditions, testicular volume, and blood circulation were documented. Results Convalescence in group A was slower than in groups B and C: Postoperative values of visual scales for pain development were higher, inability to work was 7.3 days longer, urologic effects were more severe, activities of everyday life were more reduced, and data of the German SF-36 Health Survey Test showed a significant reduction of physical condition (p < 0.05). Conclusion The compound mesh did not create more comfort for the patients than the smooth variant of the heavy-weight polypropylene mesh.     

Can Gastric Irrigation Prevent Infection During NOTES Mesh Placement?

Background  Natural orifice transluminal endoscopic surgery (NOTES) ventral hernia repair could avoid abdominal wall incisions. The infectious risk for mesh placement is of concern. We compared NOTES with laparoscopic mesh placement. Methods  Thirty-seven swine were randomized to abdominal wall polypropylene mesh placement via NOTES or laparoscopy or NOTES control. All animals received antibiotics and gastric irrigation; the laparoscopy group also received preoperative acid suppression. In the NOTES mesh group, the 2-cm² polypropylene mesh was placed using a transgastric transportation device and clipped to the anterior abdominal wall. The control animals underwent endoscopy (no gastrotomy) followed by laparoscopic mesh placement or NOTES only without mesh placement. Necropsy was performed at 14 days. Results  One NOTES mesh placement was incomplete (endoscope failure). All mesh animals survived to 14 days. At necropsy, significantly more mesh infections were noted in the NOTES mesh versus laparoscopy group (4:11 vs 0:14; p = 0.03). Gastric irrigation reduced the bacterial load significantly in all groups (p < 0.001). Infection was independent of gastric bacterial load. No difference between acid suppressed and non-suppressed animals was seen. Conclusion  The mesh placement via NOTES is technically feasible but has a high infection rate despite irrigation. Sterile conduits are needed to enable NOTES-type hernia repair with mesh. Presented at the 49th annual meeting of the Society for Surgery of the Alimentary Tract, May 21, 2008, San Diego, CA.