Robotic-assisted, laparoscopic, and open incisional hernia repair: early outcomes from the Prospective Hernia Study.

PURPOSE: To provide a comparative analysis of short-term outcomes after open, laparoscopic, and robotic-assisted (RAS) ventral incisional hernia (VIH) repairs that include subject-reported pain medication usage and hernia-related quality of life (QOL). METHODS: Subjects were ≥ 18 years old and underwent elective open, laparoscopic or RAS VIH repair without myofascial release. Perioperative clinical outcomes through 30 days were analyzed as were prescription pain medication use and subject-reported responses to the HerQLes Abdominal QOL questionnaire. Observed differences in baseline characteristics were controlled using a weighted propensity score analysis to obviate potential selection bias (inverse probability of treatment weighting, IPTW). A p value < 0.05 was considered statistically significant. RESULTS: Three hundred and seventy-one subjects (RAS, n = 159; open, n = 130; laparoscopic, n = 82) were enrolled in the study across 17 medical institutions within the United States. Operative times were significantly different between the RAS and laparoscopic groups (126.2 vs 57.2, respectively; p < 0.001). Mean length of stay was comparable for RAS vs laparoscopic (1.4 ± 1.0 vs 1.4 ± 1.1, respectively; p = 0.623) and differed for the RAS vs open groups (1.4 ± 1.0 vs 2.0 ± 1.9, respectively; p < 0.001). Conversion rates differed between RAS and laparoscopic groups (0.6% vs 4.9%; p = 0.004). The number of subjects reporting the need to take prescription pain medication through the 2-4 weeks visit differed between RAS vs open (65.2% vs 79.8%; p < 0.001) and RAS vs laparoscopic (65.2% vs 78.75%; p < 0.001). For those taking prescription pain medication, the mean number of pills taken was comparable for RAS vs open (23.3 vs 20.4; p = 0.079) and RAS vs laparoscopic (23.3 vs 23.3; p = 0.786). Times to return to normal activities and to work, complication rates and HerQLes QOL scores were comparable for the RAS vs open and RAS vs laparoscopic groups. The reoperation rate within 30 days post-procedure was comparable for RAS vs laparoscopic (0.6% vs 0%; p = 0.296) and differed for RAS vs open (0.6% vs 3.1%; p = 0.038). CONCLUSIONS: Short-term outcomes indicate that open, laparoscopic, and robotic-assisted approaches are effective surgical approaches to VIH repair; however, each repair technique may demonstrate advantages in terms of clinical outcomes. Observed differences in the RAS vs laparoscopic comparison are longer operative time and lower conversion rate in the RAS group. Observed differences in the RAS vs open comparison are shorter LOS and lower reoperation rate through 30 days in the RAS group. The operative time in the RAS vs open comparison is similar. The number of subjects requiring the use of prescription pain medication favored the RAS group in both comparisons; however, among subjects reporting a need for pain medication, there was no difference in the number of prescription pain medication pills taken. While the study adds to the body of evidence evaluating the open, laparoscopic, and RAS approaches, future controlled studies are needed to better understand pain and QOL outcomes related to incisional hernia repair. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02715622.

Thermodynamic ground state of MgB6 predicted from first principles structure search methods.

Crystalline structures of magnesium hexaboride, MgB6, were investigated using unbiased structure searching methods combined with first principles density functional calculations. An orthorhombic Cmcm structure was predicted as the thermodynamic ground state of MgB6. The energy of the Cmcm structure is significantly lower than the theoretical MgB6 models previously considered based on a primitive cubic arrangement of boron octahedra. The Cmcm structure is stable against the decomposition to elemental magnesium and boron solids at atmospheric pressure and high pressures up to 18.3 GPa. A unique feature of the predicted Cmcm structure is that the boron atoms are clustered into two forms: localized B6 octahedra and extended B∞ ribbons. Within the boron ribbons, the electrons are delocalized and this leads to a metallic ground state with vanished electric dipoles. The present prediction is in contrast to the previous proposal that the crystalline MgB6 maintains a semiconducting state with permanent dipole moments. MgB6 is estimated to have much weaker electron-phonon coupling compared with that of MgB2, and therefore it is not expected to be able to sustain superconductivity at high temperatures.

Components separation technique utilizing an intraperitoneal biologic and an onlay lightweight polypropylene mesh: "a sandwich technique".

PURPOSE: Reconstruction of large, complex abdominal wall hernias is an ongoing challenge. Primary closure of such hernias is often not possible. The components separation technique (CST) is a practical option, however, recurrence rates remain unacceptably high. In an attempt to reduce recurrences, we added a biologic underlay mesh and a lightweight polypropylene onlay mesh to the traditional CST. METHODS: Patients with a large hernia defect with or without multiple recurrences were selected to undergo a CST augmented with an acellular porcine dermal collagen mesh underlay. Following midline abdominal closure, a lightweight, large-pore polypropylene onlay mesh was fixed to the abdominal fascia. The skin and subcutaneous layers were closed over two sump drains and two closed suction drains. RESULTS: Fifty-one patients underwent a mesh-reinforced CST from May 2006 to June 2010. The study population averaged 57.9 ± 1.5 years of age with 24 males and 27 females, BMI of 34.3 ± 0.9 kg/m(2), ASA score of 2.62 ± 0.08, 29 % were smokers, 29 % were diabetic, and 69 % had at least one previous abdominal wall hernia repair. Operative time averaged 196.5 ± 7.2 min with a blood loss of 318 ± 24 mL, and average hernia defect size of 301 ± 31 cm(2). Length of follow-up averaged 20.6 ± 2.1 months; surgical site occurrences were identified in 39 %, most commonly from skin necrosis. Hernia recurrence rate was 3.9 %. CONCLUSIONS: Repair of large, complex abdominal wall hernias by CST augmented with a biologic underlay mesh and a lightweight polypropylene onlay mesh results in lower recurrence rates compared to historical reports of CST alone.

Does expanded polytetrafluoroethylene mesh really shrink after laparoscopic ventral hernia repair?

BACKGROUND: The shrinkage of mesh has been cited as a possible explanation for hernia recurrence. Expanded polytetrafluoroethylene (ePTFE) is unique in that it can be visualized on computed tomography (CT). Some animal studies have shown a greater than 40% rate of contraction of ePTFE; however, very few human studies have been performed. STUDY DESIGN: A total of 815 laparoscopic incisional/ventral hernia (LIVH) repairs were performed by a single surgical group. DualMesh Plus (ePTFE) (WL Gore & Associates, Newark, DE) was placed in the majority of these patients using both transfascial sutures and tack fixation. Fifty-eight patients had postoperative CTs of the abdomen and pelvis with ePTFE and known transverse diameter of the implanted mesh. The prosthesis was measured on the CT using the AquariusNet software program (TeraRecon, San Mateo, CA), which outlines the mesh and calculates the total length. Data were collected regarding the original mesh size, known linear dimension of mesh, seroma formation, and time interval since mesh implantation in months. RESULTS: The mean shrinkage rate was 6.7%. The duration of implantation ranged from 6 weeks to 78 months, with a median of 15 months. Seroma was seen in 8.6% (5) of patients. No relationship was identified between the percentage of shrinkage and the original mesh size (P = 0.78), duration of time implanted (P = 0.57), or seroma formation (P = 0.074). In 27.5% (16) of patients, no shrinkage of mesh was identified. Of the patients who did experience mesh shrinkage, the range of shrinkage was 2.6-25%. CONCLUSIONS: Our results are markedly different from animal studies and show that ePTFE has minimal shrinkage after LIVH repair. The use of transfascial sutures in addition to tack fixation may have an implication on the mesh contraction rates.

Laparoscopic parastomal hernia repair using a nonslit mesh technique.

BACKGROUND: The management of parastomal hernia is associated with high morbidity and recurrence rates (20-70%). This study investigated a novel laparoscopic approach and evaluated its outcomes. METHODS: A consecutive multi-institutional series of patients undergoing parastomal hernia repair between 2001 and 2005 were analyzed retrospectively. Laparoscopy was used with modification of the open Sugarbaker technique. A nonslit expanded polytetrafluoroethylene (ePTFE) mesh was placed to provide 5-cm overlay coverage of the stoma and defect. Transfascial sutures secured the mesh, allowing the stoma to exit from the lateral edge. Five advanced laparoscopic surgeons performed all the procedures. The primary outcome measure was hernia recurrence. RESULTS: A total of 25 patients with a mean age of 60 years and a body mass index of 29 kg/m2 underwent surgery. Six of these patients had undergone previous mesh stoma revisions. The mean size of the hernia defect was 64 cm2, and the mean size of the mesh was 365 cm2. There were no conversions to open surgery. The overall postoperative morbidity was 23%, and the mean hospital length of stay was 3.3 days. One patient died of pulmonary complications; one patient had a trocar-site infection; and one patient had a mesh infection requiring mesh removal. During a median follow-up period of 19 months (range, 2-38 months), 4% (1/25) of the patients experienced recurrence. CONCLUSION: On the basis of this large case series, the laparoscopic nonslit mesh technique for the repair of parastomal hernias seems to be a promising approach for the reduction of hernia recurrence in experienced hands.

Laparoscopic incisional hernia repair: are transfascial sutures necessary? A review of the literature.

BACKGROUND: Laparoscopic repair of incisional and ventral hernias is rapidly becoming more commonplace in the armamentarium of general surgeons. Its utility and low recurrence rates make it a very attractive option. As with all newer procedures, controversies exist with this approach. One significant aspect is the method of fixation for the biomaterial. Most authors add the use of transfascial sutures. Others, in the minority, do not. METHODS: A literature search using Medline and PubMed was used to evaluate the best practice for fixation in laparoscopic incisional and ventral hernia repair. RESULTS: This review of the current literature (including comparative series) seems to show that the recurrence rate is approximately 4% with the use of sutures and 1.8% without their use. However, these data do not show that there is tremendous variation in the method and manner of placing transfascial sutures or that long-term follow-up evaluation is inadequate in most series. No firm conclusions can be drawn about whether it is detrimental to omit the use of transfascial sutures. CONCLUSIONS: On the basis of this review, a larger overlap of the prosthesis (5 vs 3 cm) is necessary if sutures are not used. If sutures are used, they should be placed no more than 5 cm apart. Prospective randomized trials with and without of transfascial sutures using a consistent biomaterial are necessary to settle this issue.

Laparoscopic parastomal hernia repair.

Repair of parastomal represents a significant challenge for the hernia surgeon. Repair of these hernias is indicated because of an ill-fitting appliance, cosmetic deformity, inability to maintain proper hygiene and complications from the hernia itself such as incarceration or strangulation. Recent reports in the literature have shown that primary fascial repair can occur in 46% of patients and relocation of the stoma is associated with a 40% recurrence rate. For this reason, the use of polypropylene mesh has been applied to this repair. The recurrence rate with this open technique will still incur a failure rate of 20-29%. Additionally there are other complications such as obstruction, fistulization or mesh erosion with this biomaterial. The laparoscopic approach to this hernia may offer a new choice for this difficult problem. We have used ePTFE to repair 12 parastomal hernias with three different approaches. There have been eight colostomy, two ileostomy and two urostomy hernias. Follow-up ranges from 3-39 months (average 20 months). There has been one recurrence that required two repairs (8%). Other complications included enterotomy (one patient), ileus (one), seroma (one), and death from postoperative aspiration (one). The laparoscopic repair of parastomal hernias appears to be a promising technique for this complex dilemma.

Laparoscopic incisional and ventral hernia repair: complications-how to avoid and handle.

Complications will occur with any operative procedure. The possibility of this must be considered for laparoscopic incisional and ventral hernia repair (LIVH) as well. The most commonly reported of these include: intraoperative intestinal injury (1-3.5%), infection involving the prosthetic biomaterial (0.7-1.4%), (2.6-100%), postoperative ileus seromas (1-8%), and persistent postoperative pain (1-2%). The incidence of enterotomy can be reduced by careful dissection and judicious use of any energy source. Infection can be minimized by the use of perioperative antibiotics, an antimicrobially impregnated biomaterial, and careful manipulation of the prosthesis during the procedure. Seromas are so common that they should be expected but can be decreased by the use of a postoperative abdominal binder. Aspiration will be necessary in a few instances. Similarly, ileus is expected when there is significant bowel dissection and bleeding. Early ambulation and standard use of postoperative bowel care will aid in the treatment of this problem. Persistent pain will generally occur at the site of a transfascial suture. It cannot be predicted or prevented with certainty. When it occurs, local injection with bupivacaine, steroids, or non-steroidal agents will help, but occasionally, removal of the offending suture(s) will be required. The average recurrence rate for LIVH is approximately 5.6% in the literature. Rates as high as 15.7%, however, have been reported. Recurrence will be increased by inadequate prosthetic overlap of the fascial defect, infection that involves the biomaterial, which then requires its removal, and lack of the use of transfascial sutures. To prevent these risks, the surgeon must assure that there is at least a 3-cm overlap of all portions of the hernia defect and insist that sutures are used at 5-cm intervals to fix the biomaterial. Infection that requires explantation of the patch will generally result in recurrence, as this must be repaired primarily. Alternatively, the use of a collagen prosthesis may allow immediate repair, but this is associated with a high failure rate. A staged repair will be necessary in the future in most patients.

Laparoscopic incisional and ventral hernioplasty: lessons learned from 200 patients.

Our first 100 patients and our second 100 patients who underwent a laparoscopic repair of incisional and ventral hernias were compared and evaluated. This analysis revealed that the second group was approximately 9 years older with more comorbid medical conditions. In all, 15% were incarcerated hernias, and 21% were recurrent. Seven operations were converted to the open repair because of adhesions in five patients and either a small or large bowel injury in two patients. There were no complications related to enterotomy. Older and more infirm patients in the second group did not significantly affect outcomes. The average size of the hernia defects was 111 cm2. The average size of the prosthesis was 257.5 cm2. Larger prostheses were used in the second group. With more experience, the recurrence rates have declined from 9% to 4%. The etiology of these recurrences differed in these two groups of patients. Removal of the prosthetic due to infection was a predictable recurrence in two patients. A new hernia below the original hernia has caused us to repair the entire incision that had the initial hernia. Only one technical failure was noted, due to fracture of the suture during transfascial placement and clamping of the suture. It is not recommended to grasp any suture that remains in the patient during this hernioplasty. Recurrences were reduced because of the use of an increased overlap of the biomaterial and the use of dual methods of fixation (tacks and transfascial sutures).

Comparison of adhesion formation associated with Pro-Tack (US Surgical) versus a new mesh fixation device, Salute (ONUX Medical).

BACKGROUND: We evaluated efficacy and associated adhesion formation of an innovative mesh fixation device versus the helical tack device and analyzed two implantation techniques. METHODS: Six purpose-bred female hounds were evaluated in this 90-day survival study. Six 4-cm round patches of 1-mm thick DualMesh were fixed to the abdominal wall with either 10 Pro-Tack or 10 Salute constructs in each patch. Zero to 4 additional patches were implanted with only Salute constructs. RESULTS: Adhesion severity scores were significantly higher for middle left abdominal wall sites versus lower right and upper left sites. The adhesion dissection score was higher for group T (Pro-Tack) versus group S (Salute). CONCLUSION: No significant effects occurred with adhesion extent scores, but group T developed denser adhesions. The second analysis determined that no significant differences existed relevant to secondary Salute placement, although the total score approached significance (p < 0.09). Salute equipment was easier to handle and allowed repositioning of the patch during operation.

Management of chronic postoperative pain following incisional hernia repair with Composix mesh: a report of two cases.

There are new prosthetic biomaterials that are used to repair various defects in the abdominal wall. These have been developed within the last several years. The results of many of these products are not yet available. We report on two patients who developed chronic-pain syndromes that could only be related to the use of Composix mesh. This entity may become more conspicuous in the future, thereby presenting the surgeon with difficulty in approaching this new and difficult problem. We believe that shrinkage of the prosthesis was responsible for the pain. Both of these patients responded favorably to resection of the mesh by the open or laparoscopic technique. This was followed by repair of the fascial defect with DualMesh by the open or laparoscopic method. We were successful in the achievement of the relief of the pain and the repair of the hernia in both cases. We believe that this entity can be treated successfully by this approach. The laparoscopic method is favored.

Tissue attachment strength of prosthetic meshes used in ventral and incisional hernia repair. A study in the New Zealand White rabbit adhesion model.

BACKGROUND: Many prosthetic materials are used in incisional hernia repair, including polypropylene (PP) and expanded polytetrafluoroethylene (ePTFE). However, PP forms severe adhesions and ePTFE has raised concerns about the adequacy of tissue attachment. METHODS: The early tissue attachment strength of PP and two new forms of ePTFE (DLM and DLMC) was compared in a rabbit model (n = 12) in which disks of the three meshes (n = 8 of each material) were implanted against the abdominal wall for 3 days. RESULTS: Tensiometer testing found that DLMC mesh had significantly greater attachment strength than PP (p = 0.02). Histologic studies indicated that this was due to cellular ingrowth. Tissue adhesions were observed with all eight PP disks, one DLMC disk, and none of the DLM disks. CONCLUSION: Modified forms of ePTFE mesh may provide abdominal wall repairs that are as strong or stronger than those obtained with PP, with early tissue attachment and without adhesions.

The critical technical aspects of laparoscopic repair of ventral and incisional hernias.

Several authors have revealed the utility of the laparoscopic approach to hernia defects that involve the ventral surface of the abdominal wall. The results of these series have been favorable. These authors all have recognized that appropriate sizing and fixation are important components of this operation. The pitfalls of the laparoscopic repair of incisional hernias are few but are significant. The most important technical considerations are dissection of all adhesions and clear identification of the fascial defect, prosthesis overlap of 3 cm in all directions, and fixation by through and through sutures and spiral tacks. The attention to these factors will diminish the risk of the immediate and long-term complications of the repair of these fascial defects.

Laparoscopic incisional and ventral herniorraphy: our initial 100 patients.

A review of our initial 100 patients upon whom we attempted a laparoscopic repair of either a ventral and incisional hernia is presented. The average follow-up period of these individuals was 51 months. The operation was completed with the laparoscopic technique in 96 cases. The average defect size was 155 cm2 and the average prosthetic biomaterial size to repair these defects was 214.8 cm2. The major complication rate was 4.1%. The incidence of recurrence in these patients was 9.3%. In all of these cases of recurrence, the method of attachment was that of staples or spiral tacks alone. In 5 patients, it appeared that the prosthesis was too small to cover the defect adequately. We believe that this is an effective operation but one that has two technical mandates. The prosthetic biomaterial (DualMesh) must cover the fascial edges by a minimum of a three-centimeter overlap. Additionally, the attachment of the patch by staples or tacks alone is inadequate; consequently, the herniorraphy must include the use of through and through sutures to assure adequate fixation of the prosthesis.

Complications associated with the plug-and-patch method of inguinal herniorrhaphy.

The inguinal hernia continues to challenge general surgeons as evidenced by the variety of new surgical techniques developed to treat this malady. The persistence of recurrence rates ranging from 0.5% to as high as 20% provides the impetus to find the "best" repair. Surgeons continue to pursue an easy approach to this condition that will provide minimal patient discomfort and low to absent recurrence rates. Open tension-free and laparoscopic repairs have been shown to produce less discomfort and lower recurrence rates than conventional repairs under tension. Some of these repairs are relatively complex and difficult to learn. The use of laparoscopy can add a significant cost to the repair. Rutkow and Robbins described a tension-free technique in 1993 that promised minimal dissection, rapid return to regular activities and low recurrence rates. The plug-and-patch repair has become a very popular method of herniorrhaphy. It is a quick procedure that is relatively easily learned. Since the initial description of the procedure, there have been anecdotal reports in the surgical literature describing an occasional interesting complication of this repair. There have been no comprehensive reviews of these occurrences. It appears that there are a significant number of patients who experience prolonged pain after this operation. Additionally, this plug often will shrink to a degree that results in a recurrence of the hernia. The most important finding of this study is that, as with other surgical procedures, attention to detail must be made to mitigate against adverse events.

Laparoscopic incisional and ventral herniorrhaphy in 100 patients.

BACKGROUND: Laparoscopic incisional and ventral herniorrhaphy, a procedure first described 7 years ago, continues to gain acceptance. A series of about 100 patients who underwent the operation is described. Follow-up in this series was longer (mean 51 months) than that in previously reported series. METHODS: A retrospective review was conducted of operative and follow-up records of a series of patients scheduled to undergo laparoscopic incisional or ventral herniorrhaphy between 1992 and 1997. RESULTS: Laparoscopic repair was completed in 96 of 100 patients. The complication rate was 14%, with seromas accounting for half of the postoperative problems. Mean hospital stay was 1 day. The late recurrence rate was 9%, with 4 of the 9 recurrences developing >2 years postoperatively. CONCLUSIONS: Laparoscopic incisional and ventral herniorrhaphy is safe and effective. Most patients require hospitalization for /=3 years.

Current considerations in laparoscopic incisional and ventral herniorrhaphy.

Laparoscopic ventral and incisional herniorrhaphy is gaining popularity among both surgeons and patients. The key to the success of this procedure is avoidance of complications. In this article, important considerations in the preoperative, intraoperative, and postoperative aspects of this procedure are reviewed, with a particular focus on the repair of incisional defects. Surgical considerations to assist in the prevention of certain pitfalls associated with laparoscopic repair of ventral and incisional hernias are described.

A cost and profit analysis of hernia surgery.

The vast majority of surgeons who are in the active practice of their particular field have little time to evaluate their individual practices from a "business perspective." This fact is critical to the future of any entity that is engaged in the delivery of goods and services. Without such an analysis, few businesses will continue to function in such a manner that ensures the financial viability of that enterprise. We have attempted to accumulate the available data to analyze the practice of surgery as it relates to the cost and profit of hernia repairs. Given this information, it is easily extrapolated into other procedures, open or laparoscopic, that are performed by the general surgeon. The herniorraphy analysis indicates that one cannot hope to generate enough income to rely upon a financially successful business. The information presented should be considered a national average and not specific to an individual practice situation. It is meant to serve as a template for which each surgeon can (and must) evaluate his or her own practice profitability.

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.

Avoiding complications with laparoscopic herniorrhaphy.

Before laparoscopic inguinal hernia repair can be widely adopted, general surgeons must become familiar with the laparoscopic presentation of the inguinal anatomy and must obtain practice with an effective technique that follows the surgical tenets of a good repair. This paper discusses some of the possible pitfalls of performing laparoscopic hernia repair and presents recommendations for success, including a brief description of a technique that has been used successfully in > 60 cases.