Abdominal Wall Hernia

Laparoscopic Versus Robotic Ventral Hernia Repair - An ACHQC Database 5-Year Analysis

Introduction

To compare laparoscopic and ventral hernia repair (VHR) in the last 5 years in the United States utilizing the Abdominal Core Health Quality Collaborative (ACHQC) database.

Materials and Methods

A retrospective review of prospectively collected data from the ACHQC database was performed to include all adult patients that underwent laparoscopic and robotic VHR in the last 5 years. Univariate analysis was performed to compare outcomes from laparoscopic and robotic-assisted approaches across perioperative and postoperative outcomes.

Results

ACHQC database identified 11,096 patients with midline hernias who underwent VHR with mesh. The Laparoscopic group with patients from 2018 to 2023 (LAP) had 2,063 patients, and the robotic group (ROBO) had 9,033 patients. There was no difference in sex, age, BMI, DM, smoking status and COPD between groups. Median hernia width was 4 cm (IQR 2-6) in the ROBO group and 3 cm (IQR 2-5) in the LAP group (p < 0.001). Incisional hernia was higher in the ROBO group 5,259 (58%) versus 1,099 (53%) in the LAP group (p < 0.001). Recurrent hernia was more common in the ROBO group when compared with the LAP group (p < 0.001). Both groups had more permanent synthetic mesh. Retromuscular repair was higher in the ROBO group, 3,201 (37.6%) versus 68 (4.2%) in the LAP group (p < 0.001). The intraperitoneal repair was higher in the LAP group 1,363 (83%) versus 2,925 (34%) in the ROBO group (p < 0.001) Transversus Abdominis Release (TAR) was higher in the ROBO group 1,314 (14.5%) versus 5 (0.2%) in the LAP group (p < 0.001). Fascial closure was higher in the ROBO group (8,649; 96.5% versus 1,359; 67.3% in the LAP group p < 0.001). Regarding mesh fixation, regular suture was higher in the ROBO group 92% versus 61% in the LAP group (p < 0.001). Tacks (p < 0.001) was higher in the LAP group. The ROBO group had more patients with an operative time of 240+ minutes when compared with the LAP group (p < 0.001). There was no difference in 30-days readmission rates, recurrence, reoperation, overall postoperative complications, 30-day SSI, SSO, seroma and SSOPI between the groups.

Conclusion

The Robotic approach was associated with more technically challenging ventral hernia repairs with low complication rates over time. However, no differences in postoperative complications were found between the groups.

Causal relationship between circulating inflammatory cytokines and the risk of hernia: a bidirectional Mendelian randomization study

OBJECTIVE

Observational studies suggest a link between hernia and inflammatory cytokines, but randomized trials are limited by ethical and cost constraints. In this study, we used bidirectional Mendelian randomization (MR) to investigate the causal relationship between inflammatory cytokines and five types of hernia, aiming to inform preventive and therapeutic strategies.

METHODS

We selected 41 inflammatory factors and five types of hernia as instrumental variables, using data from the IEU Open GWAS database including individuals of European descent. The primary analysis used the inverse variance weighted method with false discovery rate (FDR) adjustment. Additional MR methods and sensitivity analyses ensured robustness. Reverse MR was used to assess potential reverse causality.

RESULTS

After FDR adjustment, stem cell growth factor beta (SCGFb) was causally associated with diaphragmatic hernia (odds ratio = 0.884, 95% confidence interval: 0.819-0.955). Reverse MR indicated that diaphragmatic hernia may increase interferon gamma-induced protein 10 (IP10) and monokine induced by interferon-gamma (MIG), and ventral hernia may elevate macrophage inflammatory protein-1b (MIP1b). Sensitivity analyses confirmed robustness.

CONCLUSION

SCGFb may protect against diaphragmatic hernia, and IP10, MIG, and MIP1b are involved in hernia development, suggesting the therapeutic potential of targeting these cytokines. Further studies are needed.

Rectus sheath nerve block for analgesia & incarcerated hernia reduction in the emergency department

BACKGROUND

Patients who present to the emergency department (ED) with incarcerated or strangulated ventral hernias are often in significant pain. Furthermore, even with procedural sedation, reduction itself also causes substantial pain. Hernias that cannot be reduced at the bedside with intravenous opioids or procedural sedation will require emergent surgery, which contributes to morbidity and mortality, especially in high-risk populations.

CASE REPORT

We present the case of a 94-year-old man with an incarcerated ventral hernia that was reduced in the ED with the aid of a rectus sheath block, ultimately avoiding the need for emergent surgical intervention.

IMPLICATIONS

Ultrasound can visualize and diagnose an incarcerated hernia, and a bilateral rectus sheath block can be performed in the ED to anesthetize the peritoneal wall, paralyze abdominal musculature, and achieve nearly painless hernia reduction.

UMBILICAL AND EPIGASTRIC HERNIA REPAIR: A SYSTEMATIC REVIEW

BACKGROUND

Umbilical and epigastric hernias are among the most common hernias of the abdominal wall; however, there is a lack of standardization for their treatment.

AIMS

To clarify the controversies regarding therapeutic possibilities, indications, and surgical techniques for umbilical and epigastric hernia repair.

METHODS

A systematic review and qualitative analysis of randomized clinical trials published in the last 20 years, involving adults (aged 18 years and over) with umbilical and/or epigastric hernias, was performed by systematically searching the PubMed/Medline, Cochrane, SciELO, and LILACS databases. The risk of bias in individual studies was assessed using the Cochrane Risk of Bias Tool.

RESULTS

Initially, 492 studies were selected and, subsequently, 15 randomized controlled clinical trials were chosen that met the inclusion criteria and underwent full reading and qualitative analysis, considering possible bias.

CONCLUSIONS

This review concluded that it is evident the superiority of the use of meshes in the repair of epigastric/primary umbilical hernias with a defect larger than 1 cm, even in certain emergency situations. However, suture repair is a good option for patients with a defect smaller than 1 cm. In the laparoscopic approach, recent evidence points towards possible superiority in fixation with fibrin sealant, and fascial defect closure is recommended. In addition, due to a scarcity of randomized controlled trials with low risk of bias, further studies are needed on types, positioning and fixation techniques, as well as the real role of video-assisted laparoscopic surgery in the correction of hernias, especially umbilical.

Botulinum toxin A in complex incisional hernia repair: a systematic review

PURPOSE

To evaluate the safety, efficacy, and short and long-term postoperative results of using BTA.

METHODS

We conducted a systematic review following the recommendations of the PRISMA method. We systematically reviewed the MEDLINE/PubMed and SCOPUS electronic databases for studies published between January 2010 and September 2021. This systematic review was registered in PROSPERO, with registration number CRD42021252445.

RESULTS

After applying the selection criteria, 11 relevant articles were selected. The total sample size was 1058 patients. Most studies aimed to assess the rate of fascial closure, followed by the rate of recurrence and reporting of postoperative complications, as well as the need for the components separation technique (CST). None of the studies reported serious complications from using BTA. Regarding fascial closure, all articles had rates above 75%, except for one. Surgical site events ranged between 19% and 29.4%. No recurrence in the group that used BTA was recorded in five studies. The other articles reported recurrence rates ranging from 6.4 to 11.4% in the groups that received BTA. The studies had varying follow-up times ranging from 1 to 49 months, with a mean of 18.6 months (± 11.2).

CONCLUSION

This review described most of the key points about the preoperative use of BTA in hernia repair. It can be concluded that the use of BTA is a safe and effective practice that promotes good short and long-term results. However, the limitations of the current literature prevent more accurate conclusions on the subject.

Long-term outcomes of PGA-TMC absorbable synthetic scaffold in both clean and contaminated ventral hernia repairs

BACKGROUND

Biosynthetic meshes afford the cost advantages of being made from fully synthetic material, but are also biodegradable, making them a versatile option that can be used in both clean and contaminated cases. The aim of this study is to evaluate the safety profile and long-term outcomes of using GORE BIO-A (BIO-A) as an adjunct to abdominal wall reconstruction in all wound classes.

METHODS

A retrospective review identified patients undergoing abdominal hernia repair using BIO-A from October 2008 to June 2018. The primary outcome was hernia recurrence rate. Only patients with at least 6-month follow-up were included when looking at recurrence rates. Secondary outcomes included 30-day morbidity categorized according to CDC Surgical Site Infection Criteria, return to operating/procedure room (RTOR), 30-day readmission, length of stay (LOS), and mortality.

RESULTS

A total of 207 patients were identified, CDC Wound Classification breakdown was 127 (61.4%), 41 (19.8%), 14 (6.8%), and 25 (12.1%) for wound classes I, II, III, and IV, respectively. Median follow-up was 55.4 months (range 0.2-162.4). Overall recurrence rate was 17.4%. Contaminated cases experienced higher recurrence rates (28.8% versus 10.4%, p = 0.002) at a mean follow up of 46.9 and 60.8 months for contaminated and clean patients, respectively. Recurrent patients had higher BMI (32.4 versus 28.4 kg/m2, p = 0.0011), larger hernias (162.2 versus 106.7 cm2, p = 0.10), higher LOS (11.1 versus 5.6 days, p = 0.0051), and higher RTOR rates (16.7% versus 5.6%, p = 0.053). 51 (24.5%) patients experienced some morbidity, including 19 (9.2%) surgical site occurences, 7 (3.4%) superficial surgical site infections, 16 (7.7%) deep surgical site infections, and 1 (0.5%) organ space infection.

CONCLUSION

This study affirms the use of biosynthetic mesh as a cost-effective alternative in all wound classifications, yielding good outcomes, limited long-term complications, and low recurrence. rates.

A ventral hernia containing appendix; a case report and literature review

INTRODUCTION AND IMPORTANCE

Abdominal wall hernia is a protrusion of abdominal contents through an acquired or congenital weakness or wall defect. A ventral hernia, including an appendix, is a rare condition. The appendix in the hernial sac is already known as inguinal and femoral hernia and has been named Amyand hernia and De Garengeot hernia, respectively.

CASE PRESENTATION

We have presented a 74-year-old woman with complaints of point tenderness in the right lower abdomen and para-umbilical and a palpable non-reducible mass over the para-umbilicus with some erythema on the skin, which started two days ago. With the help of imaging, diagnosis of abdominal wall hernia was made, with the appendix as the possible content, as there was evidence of an inflamed appendix lumen incarcerated through the abdominal wall.

CLINICAL DISCUSSION

We have provided a detailed review of recent articles. Our comprehensive discussion includes an exploration of the typical manifestations, the significance of imaging in accurate diagnosis, and the appropriate measures to facilitate optimal surgical preparation. The treatment for ventral hernia typically involves appendectomy and abdominal wall hernia repair, with the specific approach depending on the severity of inflammation.

CONCLUSION

Although abdominal wall hernia containing appendicitis is extremely rare, its clinical manifestations are hernia and acute appendicitis, the most common diseases in general surgery. Imaging may be helpful in diagnosis. According to our study, diagnostic laparoscopy could be used in case of clinical suspicion of abdominal wall hernia containing an appendix, although more studies are needed.

Ten-year outcomes following ventral hernia repair: making the case for better post-market surveillance in the USA

BACKGROUND

We sought to identify the 10-year complication and recurrence rates and associated sociodemographic and operative characteristics associated with non-mesh versus mesh-based ventral hernia repairs (VHRs).

METHODS

This was an IRB-approved (2020H0317) retrospective longitudinal study of patients undergoing mesh or non-mesh VHR from 2009-2019 at a single tertiary-care institution. The electronic medical record was used to collect sociodemographic, clinical, and intraoperative details, and early (≤ 30 days) and long-term (> 30-day) postoperative complications. Up to ten-year follow-up was obtained for long-term complications, categorized as: hernia recurrence reoperation (HRR), major complications requiring emergency surgery (MCES) (defined as non-elective operations related to the abdominal wall), and non-recurrence procedural intervention (NRPI) (defined as any procedures related to the abdominal wall, bowel, or mesh). Kaplan-Meier survival curves were obtained for each long-term complication.

RESULTS

Of the 645 patients identified, the mean age at index operation was 52.51 ± 13.57 years with 50.70% female. Of the index operations, 21.24% were for a recurrence. Procedure categories included: 57.36% incisional, 37.21% non-incisional umbilical, 8.22% non-incisional epigastric, 3.88% parastomal, 0.93% diastasis recti, and 0.47% Spigelian hernias. Operative approaches included open (n = 383), laparoscopic (n = 267), and robotic (n = 21). Fascial closure (81.55%) and mesh use (66.2%) were performed in the majority of cases. Median follow-up time was 2098 days (interquartile range 1320-2806). The rate of short-term complications was 4.81% for surgical site infections, 15.04% for surgical site occurrences, and 13.64% for other complications. At 10 years, the HRR-free survival probability was 85.26%, MCES-free survival probability was 94.44%, and NRPI-free survival probability was 78.11%.

CONCLUSIONS

A high proportion of patients experienced long-term recurrence and complications requiring intervention after index VHR. For many patients, a ventral hernia develops into a chronic medical condition. Improved efforts at post-market surveillance of operative approaches and mesh location and type should be undertaken to help optimize outcomes.

Measurement of Knowledge and Practice of Saudi Population Towards Hernias and Its Risk Factors

BACKGROUND

A hernia is an aponeurotic defect that allows an organ to protrude from its normal cavity. Despite advancements in hernia care, hernia patients' experiences with care, as well as recurrence and complication rates, are frequently suboptimal. Adequate knowledge of the risk factors of a hernia could lead to a significant reduction in the prevalence of hernia. Therefore, the current study aimed to assess the awareness of the risk factors of abdominal hernias among adults in Saudi Arabia.

METHODOLOGY

Our study is a cross-sectional analytic study to measure the level of knowledge, awareness, and practice of ventral and inguinal hernias in Saudi Arabia. The data was collected by using a valid pretested structured questionnaire taken from previous studies after getting writing approval.

RESULTS

In this study, we were able to collect data from 2611 individuals in different regions of Saudi Arabia, where 68.5% of the participants were females and 60.1% were aged between 18-29 years old. The prevalence of hernia among individuals in the current study was 9.2%, associated with participants older than 40 years old (19.1%), participants of the northern region (16.6%), illiterate individuals (30.0%), married (13.2%), and overweight or obese individuals (10.9% and 12.6%). In general, 53.7 % of the participants had a moderate level of knowledge, while 23.8% had a high level and 22.5% had a low level of knowledge.

CONCLUSION

We found a moderate level of knowledge among adult individuals in Saudi Arabia about hernia. The prevalence of hernia was similar to those reported in previous studies; however, there is a higher incidence of risk factors in the current population.

Operative time tracking for umbilical hernia patients

BACKGROUND

Army medical treatment facilities (MTFs) use a surgery scheduling system that reviews historical OR times to dictate expected procedural time when posting new cases. At a single military institution there was a noted inflation to umbilical hernia repair (UHR) times that was leading to issues with under-utilized operating rooms.

METHODS

This is a retrospective review determining what variables correlate with longer UHR operative time. Umbilical, ventral, epigastric, and incisional hernia repairs (both open and laparoscopic) were pulled from the local OR scheduling system at Dwight D. Eisenhower Army Medical Center from January 2013 to June 2018.

RESULTS

A total of 442 patients were included in the study with a mean age of 45.74 years and 54.98% male. Patient ASA level (p 0.045), primary vs. mesh repair (p < 0.001), number of hernias repaired (p 0.05), hernia size (p < 0.001), and absence of student nurse anesthetist (SRNA) (p 0.05) all correlated with longer UHR OR times. For the aggregated open hernia repair data, almost all independent variables of interest were statistically significant including age, PGY level, history of DM, case acuity, presence of SRNA, patient ASA level, patient's BMI, hernia defect size, number of hernias, history of prior repair, and history prior abdominal surgery. Multivariate regression analysis was done on the open hernia repair variables with only age and size of hernia being significant.

CONCLUSION

This data were used to create a new case request option (open UHR without mesh and open UHR with mesh) to more effectively utilize available OR time.

Preoperative computed tomography for acutely incarcerated ventral or inguinal hernia

BACKGROUND

The utility of preoperative computed tomography for urgent abdominal wall hernia repair is unclear. This study tests the hypothesis that there is no difference in patient outcomes for acutely incarcerated ventral or inguinal hernias diagnosed by preoperative computed tomography versus clinical assessment alone.

METHODS

This retrospective cohort analysis included 270 adult patients undergoing urgent repair of ventral or inguinal hernia. Demographics, risk factors for complications, operative management strategies, and 1-year outcomes were compared between patients with (n = 179) versus without (n = 91) preoperative computed tomography.

RESULTS

Among 179 preoperative computed tomography scans, 15 (8.4%) were ordered by surgeons, and all others were ordered by referring providers. The computed tomography and no computed tomography groups had similar age (58 vs 58 years, P = .77), body mass index (30.7 vs 30.6 kg/m², P = .30), American Society of Anesthesiologists class (3.0 vs 3.0, P = .39), incidence of the systemic inflammatory response syndrome (19.0% vs 20.9%, P = .75), and incidence of recurrent hernia (16.8% vs 19.8%, P = .61). The interval between admission and incision was longer in the computed tomography group (11.2 hours vs 6.6 hours, P < .001). The computed tomography and no computed tomography groups had similar duration of surgery (125 minutes in both groups, P = .88), proportions of patients with biologic mesh (21.2% vs 17.6%, P = .52) and synthetic mesh (35.2% vs 46.2%, P = .09) placement, and 1-year outcomes including incidence of superficial (8.4% vs 6.6%, P = .81) and deep or organ/space surgical site infection (5.0% vs 6.6%, P = .59), mesh explant for infection (2.2% vs 3.3%, P = .69), reoperation for recurrent hernia (3.9% vs 1.1%, P = .27), and mortality (7.8% vs 4.4%, P = .44).

CONCLUSION

The performance of preoperative computed tomography was associated with a longer interval between admission and incision and no differences in mesh placement, mesh type, or 1-year patient outcomes. These results support the safety of performing urgent repair of acutely incarcerated ventral or inguinal hernias based on clinical assessment alone.

A Pilot and Feasibility Study to Evaluate Small and Large Bite Fascial Closure Techniques

INTRODUCTION

Few randomized controlled studies have been conducted comparing a small to large fascial bite technique, yet recommendations have been made to standardize small bite closures. However, large scale randomized controlled trials require considerable effort and may benefit from a pilot study.

METHODS

This multi-center randomized controlled pilot study of adult patients undergoing median laparotomy incision investigated the feasibility of studying the outcomes between small and large surgical closure techniques.

RESULTS

Fifty of 100 planned patients consented, 32 patients completed surgery, and 19 patients completed the one-year ultrasound. Enrollment was 2.7 versus 8 patients per month pre/post addition of a study coordinator. Clinical results are summarized for feasibility demonstration purposes, but not analyzed for hypothesis testing. The total cost of the pilot study was $19,152.50 and took 22 months from first surgery to final one-year ultrasound.

CONCLUSIONS

This feasibility assessment demonstrated the complexity of planning a large-scale randomized trial evaluating small and large bite surgical closure technique. To expand this pilot study to a full scaled sample size study would require dedicated personnel and large grant funding.

Pore texture analysis in automated 3D breast ultrasound images for implanted lightweight hernia mesh identification: a preliminary study

Background

Precise visualization of meshes and their position would greatly aid in mesh shrinkage evaluation, hernia recurrence risk assessment, and the preoperative planning of salvage repair. Lightweight (LW) meshes are able to preserve abdominal wall compliance by generating less post-implantation fibrosis and rigidity. However, conventional 3D imaging techniques such as computed tomography (CT) and magnetic resonance imaging (MRI) cannot visualize the LW meshes. Patients sometimes have to undergo a second-look operation for visualizing the mesh implants. The goal of this work is to investigate the potential advantages of Automated 3D breast ultrasound (ABUS) pore texture analysis for implanted LW hernia mesh identification.

Methods

In vitro, the appearances of four different flat meshes in both ABUS and 2D hand-held ultrasound (HHUS) images were evaluated and compared. In vivo, pore texture patterns of 87 hernia regions were analyzed both in ABUS images and their corresponding HHUS images.

Results

In vitro studies, the imaging results of ABUS for implanted LW meshes are much more visualized and effective in comparison to HHUS. In vivo, the inter-class distance of 40 texture features was calculated. The texture features of 2D sectional plans (axial and sagittal plane) have no significant contribution to implanted LW mesh identification. Significant contribution was observed in coronal plane. However, since the mesh may have spatial variation such as shrinkage after implantation surgery, the inter-class distance of 3D coronal plane pore texture features are bigger than 2D coronal plane, so the contribution of 3D coronal plane pore texture features are more valuable than 2D coronal plane for implanted LW mesh identification. The use of 3D pore texture features significantly improved the robustness of the identification method in distinguishing between LW mesh and fascia.

Conclusions

An innovative new ABUS provides additional pore texture visualization, by separating the LW mesh from the fascia tissues. Therefore, ABUS has the potential to provides more accurate features to characterize pore texture patterns, and ultimately provide more accurate measures for implanted LW mesh identification.

Outcomes of Poly-4-hydroxybutyrate Mesh in Ventral Hernia Repair: A Systematic Review and Pooled Analysis

Within the past decade, poly-4-hydroxybutyrate (P4HB) biosynthetic mesh has been introduced as a potential alternative to traditional biologic and synthetic mesh in ventral hernia repair (VHR). The aim of this study was to systematically assess clinical outcomes with the P4HB in VHR.

Methods

A literature search identified all articles published in 2000 involving the use of P4HB in VHR. Descriptive statistics were used to synthesize collective data points, including postoperative outcomes. A pooled analysis of postoperative outcomes was performed using chi-square test and Fisher exact test.

Results

Across 7 studies, the P4HB was used in 453 patients. The mean rate of surgical site infection (SSI) was 6.8% (31/453), reoperation 10.7% (30/281), and recurrence 9.1% (41/453). At an average follow-up of 26.8 months, the incidence of recurrence was 10.4% (28/270). Onlay was significantly associated with increased recurrence (14.2% versus 4.4%, P = 0.001). Among sublay placements, there was no difference in recurrence in clean (Center for Disease Control [CDC] 1) or contaminated (CDC >1) wounds (2.7% versus 6.1%, P = 0.585), but contaminated wounds were associated with increased SSI (2.7% versus 15.2%, P = 0.028). Ventral Hernia Working Group grade 2 and 3 did not have different incidences of recurrence (8.0% versus 5.1%, P = 0.526) nor SSI (5.1% versus 14.6%, P = 0.265).

Conclusions

Overall, clinical outcomes of the P4HB mesh in VHR are acceptable. The P4HB mesh serves as a reliable alternative to traditional synthetic and biologic mesh across a range of defect characteristics and patient health conditions. Further research is needed to better understand the conditions in which it may provide a clinical benefit over traditional mesh types.

Chevrel technique for ventral incisional hernia. Is it still an effective procedure?

BACKGROUND

Incisional hernia still represents the most frequent late complication of abdominal surgery. After a direct repair, in literature is reported a recurrence rate ranging from 31 to 49%, meanwhile after a prosthetic repair such values were much lower, with a recurrence rate up to 10%. The sites of prosthetic placement in the abdominal wall are premusculo-aponeurotic (onlay, or Chevrel technique), retromuscular-prefascial and preperitoneal (Rives technique, Stoppa technique), whereas intraperitoneal insertion can be done with open or laparoscopic surgery. The aim of this study was to evaluate the immediate and late postoperative results in patients treated with a Chevrel technique for ventral incisional hernia.

METHODS

A retrospective review was conducted on the medical records of patients undergoing ventral hernia repair between January 2008 and December 2018 at the Emergency Surgery Unit of the Careggi University Hospital in Florence.

RESULTS

Between January 2008 and December 2018 at the Emergency Surgery Unit of the Careggi University Hospital in Florence, 461 patients (245 male, 216 female) with a mean age of 61,52 years were submitted to ventral incisional hernia repair with a Chevrel technique. The mean operatory time was 95.29 min (±50.48) and in 72 patients (15.61%) human fibrin glue was vaporized under the mesh using a spray device. Mean postoperative hospital stay was 5 days and all drain tubes were removed after 7.1 days as mean (±4.3). No intraoperative mortality nor postoperative mortality was reported. In our experience the Chevrel technique for ventral incisional hernia show a recurrence rate (3.2%). Parietal complications observed were seroma in 7.1% of patients, hematoma in 4.7%, localized skin necrosis in 5.2%, surgical site infection in 6.7%, data comparable with the results reported in the other studies.

CONCLUSIONS

Most of the objections to the Chevrel procedure focus on the parietal complications and risk of infection. Chevrel procedure cannot be considered an obsolete intervention, in our series, results were very satisfactory in both immediate and late follow-up; moreover this technique is safe and easy to perform.

Use of Shear Wave Elastography to Quantify Abdominal Wall Muscular Properties in Patients With Incisional Hernia

Shear wave elastography (SWE) is a potential modality that quantitatively measures the elasticity (shear wave speed [SWS]) of musculoskeletal structure. This SWS was bilaterally measured in the rectus abdominis (RA), external oblique (EO) muscle, internal oblique (IO) muscle and transversus abdominis (TrA) using SWE in 28 patients with incisional hernia and 14 healthy controls. The differences in muscle thickness for IO and TrA were significant between the two groups (p < 0.05). The SWS of RA, EO, IO and TrA was significantly higher in the incisional hernia patient group than in the healthy controls (p < 0.05). Significant differences were also observed between the upper and lower points in both groups (p < 0.05). The measurements of SWS help in evaluating the elastic properties of abdominal wall muscles, which could further aid in preparing treatment plans to improve muscle strength.

Stoma closure and reinforcement (SCAR): A study protocol for a pilot trial

A quality metric for centers performing rectal cancer surgery is a high percentage of sphincter sparing procedures. These procedures often involve temporary bowel diversion to minimize the complications of an anastomotic leak. The most common strategy is a diverting loop ileostomy which is then closed after completion of adjuvant therapy or the patient recovers from surgery. Loop ileostomy is not without complications and the closure is complicated by a one in three chance of incisional hernia development. Strategies to prevent this problem have been designed using a variety of techniques with and without mesh placement. This proposed pilot study will test the safety and efficacy of a novel stoma closure technique involving permanent mesh in the retro rectus position during ileostomy closure. The study will prospectively follow 20 patients undergoing ileostomy closure using this technique and evaluate for safety of the procedure, quality of life, and feasibility for a larger randomized controlled trial. Patients will be followed post procedurally and evaluated for 30-day complications, as well as followed up with routine cancer surveillance computed tomography every 6 months in which the presence of stoma site incisional hernias will be evaluated. The results of this pilot study will inform the design of a multiple center, blinded randomized controlled trial to evaluate the utility of permanent mesh placement to decrease the incidence of prior stoma site incisional hernias.

Left lower transverse incision versus Pfannenstiel-Kerr incision for specimen extraction in laparoscopic sigmoidectomy: a match pair analysis

OBJECTIVE

The ideal location of specimen extraction in laparoscopic-assisted colorectal surgery is still debatable. The aim of this study was to compare the incidence of incisional hernias and surgical site infections in patients undergoing elective laparoscopic resection for recurrent sigmoid diverticulitis by performing specimen extraction through left lower transverse incision or Pfannenstiel-Kerr incision.

METHODS

A total of 269 patients operated between January 2014 and December 2017 were retrospectively screened for inclusion in the study. Patients with specimen extraction through left lower transverse incision (LLT) and patients with specimen extraction through Pfannenstiel-K incision (P-K) were matched in 1:1 proportion regarding age, sex, comorbidities, and previous abdominal surgery. The incidence of incisional hernias and surgical site infections were compared by using Fisher's exact test.

RESULTS

After matching 77 patients in the LLT group and 77 patients in the P-K group, they were found to be homogenous regarding the above mentioned descriptive characteristics. No patients in the P-K group developed an incisional hernia compared with 10 patients (13%) in the LLT group (p = 0.001). All these patients required hernia repair with mesh augmentation. The rate of surgical site infections was 1/77 in the P-K group and 0/77 in the LLT group (p = 1.0). In the P-K group, a wound protector was used in 86% of patients whereas in the LLT group, 39% of the wounds were protected during specimen extraction (p < 0.0001).

CONCLUSION

The Pfannenstiel-Kerr incision may be the preferred extraction site compared with the left lower transverse incision given the significant reduction of the risk of incisional hernias.

Outcomes of Open Complex Ventral Hernia Repairs With Retromuscular Placement of Poly-4-Hydroxybutyrate Bioabsorbable Mesh

Purpose. Optimal technique and mesh selection still debated for complex ventral hernias. Limited data exists on bioabsorbable meshes in high-risk patients. We evaluated our experience. Methods. Retrospective review was conducted following institutional review board approval for ventral hernia repairs using a single bioabsorbable mesh between February 2014 and November 2017. Patient and hernia details characterized. Outcomes evaluated. Results. 20 ventral hernia repairs identified, 10 males, 10 females. Mean body mass index was 35 ± 7.4 kg/m², and mean age 47 ± 13 years. Comorbid conditions were diabetes 35% and hypertension 40%. Fifty-five percent had American Society of Anesthesiologist scores of 3. Hernia Characteristics: Ventral Hernia Working Group Grade 3 hernias were 80%, and remainder grade 2. Forty percent of hernias were Centers for Disease Control class III, and remainder were class I and II. The mean defect size was 533 cm² ± 500. Repair for prior open abdomens was 45%, recurrent hernias 20%, incisional 15%, incarcerated 10%, incisional with parastomal 5%, and primary ventral 5%. Concomitant bowel procedures in 8, (40%). All cases had retromuscular mesh placement (transversus abdominus release 65%, Rives-Stoppa 35%). Surgical site occurrences were 20% (surgical site infection 10%, seroma 10%). Overall hospital stay 5 ± 3 days. Ileus occurred in 20%. One postoperative death due to fatal arrhythmia. There were no recurrences with mean follow-up 21.1 months. Conclusions. Complex hernia repairs using bioabsorbable mesh were conducted in a small cohort of high-risk patients. These data demonstrate good outcomes with limited morbidity and mortality. There were no recurrences.

Optimized wound closure using a biomechanical abdominal model

BACKGROUND

Suturing techniques for midline abdominal wall incisions vary between surgeons. This study uses a biomechanical abdominal model to assess tissue stretch using different suturing techniques for midline laparotomy closure.

METHODS

Deformation tests were performed on the linea alba of 48 porcine abdominal walls. Each pattern was tested three times at pressures ranging from 0 to 20 kPa using different continuous suturing techniques and a control.

RESULTS

There was a sevenfold improvement when the best performing bite separation and bite width ([5, 16] mm) was compared with the most poorly performing combination ([15, 4] mm). The traditional bite and width separation ([10, 10] mm) and the recently proposed combination ([5, 5] mm) may not be optimal, and substantial improvements in surgical outcome may be achieved by changing to a [5,16]-mm combination.

CONCLUSION

These findings suggest using a small bite separation (5 mm) and large bite width (16 mm) during abdominal wound closure may be optimal. Surgical relevance Suturing techniques for midline abdominal wall incisions vary between surgeons. This experimental study suggests substantial potential for improved tissue apposition by changing the suturing approach from the traditional clinical recommendation of 10 mm for both bite separation and bite width to a bite separation of 5 mm and a bite width of 16 mm. These findings support recent European Hernia Society guidelines and the recent randomized STITCH (Suture Techniques to Reduce the Incidence of The inCisional Hernia) trial, which found that small separations are more effective than large separations, but suggest that they should be combined with large bite depths.

Controlled Levofloxacin Release and Antibacterial Properties of β-Cyclodextrins-Grafted Polypropylene Mesh Devices for Hernia Repair

Mesh infection is a major complication of hernia repair. After knitted mesh implantation, bacteria can grow within textile structures causing infection. In this work, polypropylene (PP) mesh devices were two-step grafted with hexamethylene diisocyanate (HDI) and β⁻cyclodexrins (CD) and then loaded with suitable antimicrobial levofloxacin HCL for hernia mesh-infection prevention. First, oxygen plasma was able to create surface roughness, then HDI was successfully grafted onto PP fiber surfaces. Afterwards, CD was covalently grafted onto the HDI treated PP meshes, and levofloxacin HCL (LVFX) was loaded into the CD cavity of the modified meshes. The modified devices were evaluated for sustained antibiotic properties and drug-release profiles in a phosphate buffer, and sustained drug release was observed between interfaces of meshes and aqueous environment. The antibiotic-loaded PP mesh samples demonstrated sustained antibacterial properties for 7 and 10 days, respectively, against both Gram-negative and Gram-positive bacteria. The CD-captured levofloxacin HCL showed burst release after 6 h but later exhibited sustained release for the next 48 h. Among all samples, the modified mesh LVFX-6 was more stable and showed more sustained drug release and could be employed in future clinical applications.

Multicenter, Prospective, Longitudinal Study of the Recurrence, Surgical Site Infection, and Quality of Life After Contaminated Ventral Hernia Repair Using Biosynthetic Absorbable Mesh: The COBRA Study

OBJECTIVE

The aim of the study was to evaluate biosynthetic absorbable mesh in single-staged contaminated (Centers for Disease Control class II and III) ventral hernia (CVH) repair over 24 months.

BACKGROUND

CVH has an increased risk of postoperative infection. CVH repair with synthetic or biologic meshes has reported chronic biomaterial infections and high hernia recurrence rates.

METHODS

Patients with a contaminated or clean-contaminated operative field and a hernia defect at least 9 cm had a biosynthetic mesh (open, sublay, retrorectus, or intraperitoneal) repair with fascial closure (n = 104). Endpoints included overall Kaplan-Meier estimates for hernia recurrence and postoperative wound infection rates at 24 months, and the EQ-5D and Short Form 12 Health Survey (SF-12). Analyses were conducted on the intent-to-treat population, and health outcome measures evaluated using paired t tests.

RESULTS

Patients had a mean age of 58 years, body mass index of 28 kg/m, 77% had contaminated wounds, and 84% completed 24-months follow-up. Concomitant procedures included fistula takedown (n = 24) or removal of infected previously placed mesh (n = 29). Hernia recurrence rate was 17% (n = 16). At the time of CVH repair, intraperitoneal placement of the biosynthetic mesh significantly increased the risk of recurrences (P ≤ 0.04). Surgical site infections (19/104) led to higher risk of recurrence (P < 0.01). Mean 24-month EQ-5D (index and visual analogue) and SF-12 physical component and mental scores improved from baseline (P < 0.05).

CONCLUSIONS

In this prospective longitudinal study, biosynthetic absorbable mesh showed efficacy in terms of long-term recurrence and quality of life for CVH repair patients and offers an alternative to biologic and permanent synthetic meshes in these complex situations.

Procedural volume, cost, and reimbursement of outpatient incisional hernia repair: implications for payers and providers

OBJECTIVE

This analysis aimed to evaluate trends in volumes and costs of primary elective incisional ventral hernia repairs (IVHRs) and investigated potential cost implications of moving procedures from inpatient to outpatient settings.

METHODS

A time series study was conducted using the Premier Hospital Perspective^® Database (Premier database) for elective IVHR identified by International Classification of Diseases, Ninth revision, Clinical Modification codes. IVHR procedure volumes and costs were determined for inpatient, outpatient, minimally invasive surgery (MIS), and open procedures from January 2008-June 2015. Initial visit costs were inflation-adjusted to 2015 US dollars. Median costs were used to analyze variation by site of care and payer. Quantile regression on median costs was conducted in covariate-adjusted models. Cost impact of potential outpatient migration was estimated from a Medicare perspective.

RESULTS

During the study period, the trend for outpatient procedures in obese and non-obese populations increased. Inpatient and outpatient MIS procedures experienced a steady growth in adoption over their open counterparts. Overall median costs increased over time, and inpatient costs were often double outpatient costs. An economic model demonstrated that a 5% shift of inpatient procedures to outpatient MIS procedures can have a cost surplus of ∼ US $1.8 million for provider or a cost-saving impact of US $1.7 million from the Centers for Medicare & Medicaid Services perspective.

LIMITATIONS

The study was limited by information in the Premier database. No data were available for IVHR cases performed in free-standing ambulatory surgery centers or federal healthcare facilities.

CONCLUSION

Volumes and costs of outpatient IVHRs and MIS procedures increased from January 2008-June 2015. Median costs were significantly higher for inpatients than outpatients, and the difference was particularly evident for obese patients. A substantial cost difference between inpatient and outpatient MIS cases indicated a financial benefit for shifting from inpatient to outpatient MIS.

Robotic Transversus Abdominis Release (TAR): is it possible to offer minimally invasive surgery for abdominal wall complex defects?

ABSTRACT We describe the preliminary national experience and the early results of the use of robotic surgery to perform the posterior separation of abdominal wall components by the Transversus Abdominis Release (TAR) technique for the correction of complex defects of the abdominal wall. We performed the procedures between 04/2/2015 and 06/15/2015 and the follow-up time was up to six months, with a minimum of two months. The mean surgical time was five hours and 40 minutes. Two patients required laparoscopic re-intervention, since one developed hernia by peritoneal migration of the mesh and one had mesh extrusion. The procedure proved to be technically feasible, with a still long surgical time. Considering the potential advantages of robotic surgery and those related to TAR and the results obtained when these two techniques are associated, we conclude that they seem to be a good option for the correction of complex abdominal wall defects.

The suture pullout characteristics of human and porcine linea alba

There is a substantial prevalence of post-operative incisional hernia for both laparoscopic and laparotomy procedures, but there have been few attempts at quantifying abdominal wound closure methodology in the literature. One method to ascertain a more robust method of wound closure is the identification of the influence of suture placement parameters on suture pullout force. Current surgical practice involves a recommended bite depth and bite separation of 10mm, but the evidence base for this is not clear. In this paper, the suture pullout characteristics of both porcine and human linea alba were investigated to ascertain a suture placement protocol for surgical wound closure. Uniaxial suture pullout force testing on fresh frozen porcine and human linea alba samples was performed using standard materials testing machines. The influence of the number of suture loops, the bite depth and the bite separation of the sutures and the orientation of the sutures with respect to the principal fibre direction in the linea alba were assessed. Results showed a clearly identifiable relationship between pullout force of the suture, bite separation and bite depth, with low suture separation and high suture depth as optimal parameters for increasing pullout force. Resistance to pullout could be improved by as much as 290% when optimizing test conditions. Both human and porcine tissue were observed to exhibit very similar pullout force characteristics, corroborating the use of a porcine model for investigations into wound closure methodology. Orientation of suture application was also found to significantly affect the magnitude of suture pullout, with suturing applied longitudinally across a transverse defect resulting in higher pullout forces for small suture bite separations. Although further assessment in an environment more representative of in vivo conditions is required, these findings indicate that increasing the bite depth and reducing the bite separation with respect to the current surgical recommendations may reduce the risk of post-operative incisional hernia.

Discovery of novel plasma proteins as biomarkers for the development of incisional hernias after midline incision in patients with colorectal cancer: The ColoCare study

BACKGROUND

Ventral incisional hernia is the most common long-term complication after an abdominal operation. Among newly diagnosed colorectal cancer patients, we screened the preoperative plasma proteome to explore predictive markers for the development of an incisional hernia.

METHODS

We utilized preoperative plasma samples of 72 newly diagnosed colorectal cancer patients who underwent midline incision for tumor resection between 2010 and 2013. A total of 21 patients with incisional hernia occurrence were matched with 51 patients with at least 18 months follow-up without an incisional hernia by sex, age, and body mass index. To assess predictive markers of incisional hernia risk, we screened the plasma proteome for >2,000 distinct proteins using a well-validated antibody microarray test. Paired t tests were used to compare protein levels between cases and controls. A gene-set-enrichment analysis (Gene Ontology and Kyoto Encyclopedia of Genes and Genomes) was applied to test for differences in signaling pathways between the 2 groups.

RESULTS

The proteome screen identified 25 proteins that showed elevated or reduced plasma levels in the hernia group compared to the control group (nominal P values < .05). Several proteins were in pathways associated with wound healing (CCL21, SHBG, BRF2) or cell adhesion (PCDH15, CDH3, EPCAM).

CONCLUSION

Our study shows that there are multiple individual and groups of plasma proteins that could feasibly predict the personal hernia risk prior to undergoing an operation. Further investigations in larger, independent sample sets are warranted to replicate findings and validate clinical utility of potential biomarkers. After validation, such a biomarker could be incorporated into a multifactorial risk model to guide clinical decision-making.

Impact of the Specific Extraction-Site Location on the Risk of Incisional Hernia After Laparoscopic Colorectal Resection

BACKGROUND

The impact of the specific incision used for specimen extraction during laparoscopic colorectal surgery on incisional hernia rates relative to other contributing factors remains unclear.

OBJECTIVE

This study aimed to assess the relationship between extraction-site location and incisional hernia after laparoscopic colorectal surgery.

DESIGN

This was a retrospective cohort study (January 2000 through December 2011).

SETTINGS

The study was conducted at a high-volume, specialized colorectal surgery department.

PATIENTS

All of the patients undergoing elective laparoscopic colorectal resection were identified from our prospectively maintained institutional database.

MAIN OUTCOME MEASURES

Extraction-site and port-site incisional hernias clinically detected by physician or detected on CT scan were collected. Converted cases, defined as the use of a midline incision to perform the operation, were kept in the intent-to-treat analysis. Specific extraction-site groups were compared, and other relevant factors associated with incisional hernia rates were also evaluated with univariate and multivariate analyses.

RESULTS

A total of 2148 patients (54.0% with abdominal and 46.0% with pelvic operations) with a mean age of 51.7 ± 18.2 years (52% women) were reviewed. Used extraction sites were infraumbilical midline (23.7%), stoma site/right or left lower quadrant (15%), periumbilical midline (22.5%), and Pfannenstiel (29.6%) and midline converted (9.2%). Overall crude extraction site incisional hernia rate during a mean follow-up of 5.9 ± 3.0 years was 7.2% (n = 155). Extraction-site incisional hernia crude rates were highest after periumbilical midline (12.6%) and a midline incision used for conversion to open surgery (12.0%). Independent factors associated with extraction-site incisional hernia were any extraction sites compared with Pfannenstiel (periumbilical midline HR = 12.7; midline converted HR = 13.1; stoma site HR = 28.4; p < 0.001 for each), increased BMI (HR = 1.23; p = 0.002), synchronous port-site hernias (HR = 3.66; p < 0.001), and postoperative superficial surgical-site infection (HR = 2.11; p < 0.001).

LIMITATIONS

This study was limited by its retrospective nature, incisional hernia diagnoses based on clinical examination, and heterogeneous surgical population.

CONCLUSIONS

Preferential extraction sites to minimize incisional hernia rates should be Pfannenstiel or incisions off the midline. Midline incisions should be avoided when possible.

Umbilical hernias: the cost of waiting

BACKGROUND

Umbilical hernias are well described in the literature, but its impact on health care is less understood. The purpose of this study was to investigate the effect of non-operative management of umbilical hernias on cost, work absenteeism, and resource utilization.

METHODS

The Truven Health Database, consisting of 279 employers and over 3000 hospitals, was reviewed for all umbilical hernia patients, aged 18-64 who were enrolled in health plans for 12 months prior to surgery and 12 months after surgery. Patients were excluded if they had a recurrence or had been offered a "no surgery" approach within 1 year of the index date. The remaining patients were separated into surgery (open or laparoscopic repair) or no surgery (NS). Post-cost analysis at 90 and 365 days and estimated days off from work were reviewed for each group.

RESULTS

The non-surgery cohort had a higher proportion of females and comorbidity index. Adjusted analysis showed significantly higher 90 and 365 costs for the surgery group (p < 0.0001), though the cost difference did decrease over time. NS group had significantly higher estimated days of health-care utilization at both the 90 (1.99 vs. 3.58 p < 0.0001) and 365 (8.69 vs. 11.04 p < 0.0001) day post-index mark. A subgroup analysis demonstrated laparoscopic repair had higher costs compared to open primarily due to higher index procedure costs (p < 0.05).

CONCLUSIONS

Though the financial costs were found to be higher in the surgery group, the majority of these were due to the surgery itself. Significantly higher days of health-care utilization and estimated days off work were experienced in the NS group. It is our belief that early operative intervention will lead to decreased costs and resource utilization.

Systemic inflammatory cytokine analysis to monitor biomaterial augmented tissue healing

PURPOSE

Hernias can be repaired by reinforcement of damaged fascia using biomaterials to provide stabilisation. Repair materials are usually porous, through which cells infiltrate, proliferate and secrete ECM. Their efficacy relies on good tissue integration and resolution of host defence mechanisms. Therefore, understanding the dynamics by which biomaterials interact with tissue will provide knowledge to advance prosthesis design. Furthermore, determining host response in real time would provide significant advantage both clinically and scientifically over the current terminal process of histology.

METHODS

3 materials comprising synthetic and composite (synthetic materials hybridised with a resorbable biologic component) meshes were implanted into a rat full-thickness abdominal wall excision model. Their efficacy was evaluated using histopathology whilst also monitoring systemic concentrations of cytokines associated with inflammation and wound healing to predict material outcome over 12 weeks.

RESULTS

The noncomposite material (polyester) and Material B (polypropylene mesh with oligocaprone film and polydioxanone glue) stimulated the largest degree of adhesion from the 3 materials tested, although after 28 days adhesions were stronger to Material B. Histologically, all 3 materials integrated well with abdominal musculature and infiltrated completely with cells.

CONCLUSIONS

Analysis of systemic inflammation biomarkers confirmed inflammation elicited by surgeries and meshes irrespective of their composition. However, at an early postoperative endpoint (i.e., 1 week), some biomarkers, namely, IL-18 and RANTES, appeared to discriminate the noncomposite mesh from the composite materials, although in this study all materials successfully repaired the defects without recurrence or external indicators of postoperative chronic pain.

Ventral hernias in morbidly obese patients: a suggested algorithm for operative repair

With the rise in prevalence of obesity, most general surgeons will have to face the problem of the obese patient with an abdominal wall defect. Treatment of these bariatric patients raises unique challenges, and at this time there is still no consensus on the best treatment option. This study was performed in a high-volume bariatric and minimally invasive surgery center at a tertiary care facility in the USA. Twenty-eight morbidly obese patients treated at our facility between 2003 and 2008 were separated into four groups according to anatomic features and symptoms. Patients with the following characteristics were classified as having a favorable anatomy: body mass index not exceeding 50 kg/m(2), gynecoid body habitus, reducible hernias found in a central location, abdominal wall thickness less than 4 cm, and the defect's largest diameter not exceeding 8 cm. All other patients were classified as having an unfavorable anatomy. In this study, we report a systematic treatment approach for the morbidly obese patient presenting with a ventral hernia based on whether the hernia is symptomatic or asymptomatic, as well as the distinct characteristics of the hernia and body habitus features. We followed up on these patients postoperatively for at least 2 years, with a mean follow-up period of 30 months. Only a total of three hernia recurrences were observed. Successful treatment of ventral hernias in morbidly obese patients should be individualized based on the patient's symptoms and defined hernia characteristics.

Obesity Increases the Odds of Acquiring and Incarcerating Noninguinal Abdominal Wall Hernias

The current data available describing the relationship of obesity and abdominal wall hernias is sparse. The objective of this study was to investigate the current prevalence of noninguinal abdominal wall hernias and their correlation with body mass index (BMI) and other demographic risk factors. Patients with umbilical, incisional, ventral, epigastric, or Spigelian hernias with or without incarceration were identified using the regional database for 14 hospitals over a 3-year period. Patients were stratified based on their BMI. Univariate and multivariate analyses were performed to distinguish other significant risk factors associated with the hernias. Of 2,807,414 patients, 26,268 (0.9%) had one of the specified diagnoses. Average age of the patients was 52 years and 61 per cent were male. The majority of patients had nonincarcerated umbilical hernias (74%). Average BMI was 32 kg/m2. Compared with patients with a normal BMI, the odds of having a hernia increased with BMI: BMI of 25 to 29.9 kg/m2 odds ratio (OR) 1.63, BMI of 30 to 39.9 kg/m2 OR 2.62, BMI 40 to 49.9 kg/m2 OR 3.91, BMI 50 to 59.9 kg/m2 OR 4.85, and BMI greater than 60 kg/m2 OR 5.17 ( P < 0.0001). Age older than 50 years was associated with a higher risk for having a hernia (OR, 2.12; 95% [CI], 2.07 to 2.17), whereas female gender was associated with a lower risk (OR, 0.53; 95% CI, 0.52 to 0.55). Those with incarcerated hernias had a higher average BMI (32 kg/m2 vs 35 kg/m2; P < 0.0001). Overall, BMI greater than 40 kg/m2 showed an increased chance of incarceration, and a BMI greater than 60 kg/m2 had the highest chance of incarceration, OR 12.7 ( P < 0.0001). Age older than 50 years and female gender were also associated with a higher risk of incarceration (OR, 1.28; 95% CI, 1.02 to 1.59 and OR, 1.80; CI, 1.45 to 2.24). Increasing BMI and increasing age are associated with a higher prevalence and an increased risk of incarceration of noninguinal abdominal wall hernias.

Management of non-midline incisional hernia by the laparoscopic approach: results of a long-term follow-up prospective study

BACKGROUND

The role of the laparoscopic approach in the repair of non-midline incisional hernias is controversial due to the absence of adequate scientific studies. This study aimed to determine the safety and efficacy of laparoscopic repair for non-midline incisional hernias.

METHODS

This prospective clinical study was conducted in an abdominal wall unit of a teaching hospital. Patients underwent surgery for non-midline incisional hernias using the laparoscopic approach (n = 73) and were classified into three groups: subcostal, iliac, and lumbar. The primary end point was recurrence. The secondary end points were intraoperative parameters, comorbidity, and patient outcomes. The median follow-up period was 62 months (range, 36-170 months).

RESULTS

No hospital stay was needed for 34% of the patients. The remaining patients needed an average hospital stay of 2.7 days. The most frequent morbidity was hematoma. The overall recurrence rate was 8.2% and was higher for the subcostal hernias (25%). The three groups differed in size, local morbidity, and recurrence (P < 0.05). The independent risk factors for recurrence were size (hazard ratio [HR], 2.16; 95% confidence interval [CI], 1.08-4.33) and local morbidity (HR 30.62; 95% CI 1.22-768-82). The best predictor of recurrence was a hernia diameter greater than 15 cm. The only predictive factor of local morbidity was obesity (P < 0.007).

CONCLUSIONS

The laparoscopic approach is a safe and effective treatment for non-midline incisional hernias. Caution should be taken with subcostal hernias, obese patients, and a defect size greater than 15 cm. An algorithm is suggested to guide the "rational" treatment of non-midline incisional hernias.

Histologic and biomechanical evaluation of a novel macroporous polytetrafluoroethylene knit mesh compared to lightweight and heavyweight polypropylene mesh in a porcine model of ventral incisional hernia repair

PURPOSE

To evaluate the biocompatibility of heavyweight polypropylene (HWPP), lightweight polypropylene (LWPP), and monofilament knit polytetrafluoroethylene (mkPTFE) mesh by comparing biomechanics and histologic response at 1, 3, and 5 months in a porcine model of incisional hernia repair.

METHODS

Bilateral full-thickness abdominal wall defects measuring 4 cm in length were created in 27 Yucatan minipigs. Twenty-one days after hernia creation, animals underwent bilateral preperitoneal ventral hernia repair with 8 × 10 cm pieces of mesh. Repairs were randomized to Bard(®)Mesh (HWPP, Bard/Davol, http://www.davol.com), ULTRAPRO(®) (LWPP, Ethicon, http://www.ethicon.com), and GORE(®)INFINIT Mesh (mkPTFE, Gore & Associates, http://www.gore.com). Nine animals were sacrificed at each timepoint (1, 3, and 5 months). At harvest, a 3 × 4 cm sample of mesh and incorporated tissue was taken from the center of the implant site and subjected to uniaxial tensile testing at a rate of 0.42 mm/s. The maximum force (N) and tensile strength (N/cm) were measured with a tensiometer, and stiffness (N/mm) was calculated from the slope of the force-versus-displacement curve. Adjacent sections of tissue were stained with hematoxylin and eosin (H&E) and analyzed for inflammation, fibrosis, and tissue ingrowth. Data are reported as mean ± SEM. Statistical significance (P < 0.05) was determined using a two-way ANOVA and Bonferroni post-test.

RESULTS

No significant difference in maximum force was detected between meshes at any of the time points (P > 0.05 for all comparisons). However, for each mesh type, the maximum strength at 5 months was significantly lower than that at 1 month (P < 0.05). No significant difference in stiffness was detected between the mesh types or between timepoints (P > 0.05 for all comparisons). No significant differences with regard to inflammation, fibrosis, or tissue ingrowth were detected between mesh types at any time point (P > 0.09 for all comparisons). However, over time, inflammation decreased significantly for all mesh types (P < 0.001) and tissue ingrowth reached a slight peak between 1 and 3 months (P = 0.001) but did not significantly change thereafter (P > 0.09).

CONCLUSIONS

The maximum tensile strength of mesh in the abdominal wall decreased over time for HWPP, LWPP, and mkPTFE mesh materials alike. This trend may actually reflect inability to adequately grip specimens at later time points rather than any mesh-specific trend. Histologically, inflammation decreased with time (P = 0.000), and tissue ingrowth increased (P = 0.019) for all meshes. No specific trends were observed between the polypropylene meshes and the monofilament knit PTFE, suggesting that this novel construction may be a suitable alternative to existing polypropylene meshes.

Repair of complex incisional hernias using double prosthetic repair: single-surgeon experience with 50 cases

BACKGROUND

The treatment of complex incisional hernias is still difficult and controversial. With technologic developments we can modify and update the operative techniques described for treating complex abdominal wall hernias.

METHODS

This is a prospective study of 50 patients with complex incisional hernias undergoing complex abdominal wall herniorrhaphy at a university hospital. All patients were evaluated in a multidisciplinary clinic dedicated to abdominal wall reconstruction. All patients underwent pre-operative computed tomography. Complex incisional hernias were regarded as those with multiple recurrences (>3 times), a previous mesh complicated by fistula and chronic infection, giant diffuse lumbar hernias, an associated parastomal hernia, or hernias developing after bariatric surgery. The operative technique was a double reconstruction prosthetic mesh. The type of repair as well as clinical, operative, and follow-up data were analyzed.

RESULTS

Eight patients had considerable loss of tissue, 5 had trophic skin lesions, and 2 had chronic suppurative infection. The mean size of the defects was 18.2 cm. Morbidity included 5 cases of seroma, 2 neuralgias, and 2 cutaneous necroses. The mean duration of hospital stay was 5 days (range, 2-9). Complete follow-up (mean, 48 months; range, 12-108) showed no recurrent hernias.

CONCLUSION

While awaiting a longer follow-up to confirm the results, we conclude that complex incisional hernias can be repaired safely and with a low morbidity and recurrence rate by means of a double prosthetic repair technique.

Hydrated vs. freeze-dried human acellular dermal matrix for hernia repair: a comparison in a rabbit model

BACKGROUND

Abdominal wall hernias commonly occur following laparotomy. Biologic grafts are used to treat these hernias due to their biocompatibility and their ability to serve as a matrix for tissue regeneration and remodeling. Freeze-dried human acellular dermal matrices (F-HADMs) have been shown to be effective in abdominal wall defect repair. Hydrated human acellular dermal matrices (H-HADMs) have not been previously evaluated. This study evaluates H-HADM and F-HADM in the repair of abdominal wall hernias in the rabbit.

METHODS

Thirty-six 3-4-kg New Zealand white rabbits underwent laparotomy with the creation of a hernia. After defect reperitonealization, the animals underwent hernia repair with H-HADM, F-HADM, or primary repair. Within each group, four animals were survived for 4, 8, and 20 weeks. The outcomes evaluated included recurrences, adhesions, histology, immunohistochemistry, and tensiometry.

RESULTS

Thirty-five animals underwent abdominal wall hernia repair. One animal in the F-HADM group developed a recurrent hernia. No significant difference was demonstrated in adhesion scores between the H-HADM (0.75) and F-HADM (0.83) groups. Tensiometry demonstrated no differences in the forces required to disrupt the graft from the native fascia between H-HADM and F-HADM at any time point. H-HADM demonstrated fewer white blood cells (WBC) and eosinophils (EOS) per high-powered field (hpf) than F-HADM at 4 weeks (144 WBC/hpf vs. 534 WBC/hpf, P < 0.05; 87 EOS/hpf vs. 304 EOS/hpf, P < 0.05) and 8 weeks (104 WBC/hpf vs. 314 WBC/hpf, P < 0.05; 41 EOS/hpf vs. 149 EOS/hpf, P < 0.05). At 20 weeks, there was no difference in WBC or EOS (134 WBC/hpf vs. 144 WBC/hpf, P = NS; 86 EOS/hpf vs. 104 EOS/hpf, P = NS). Immunohistochemistry for CD31 demonstrated no difference in vascularity at any time point.

CONCLUSIONS

H-HADM and F-HADM demonstrate comparable results in abdominal wall hernia treatment in a rabbit model. With both grafts, the weakest area of the repair occurs at the graft and native fascia interface. Hernia repairs with H-HADM and F-HADM demonstrate similar incidences of adhesions and tensile strength characteristics. H-HADM demonstrates a reduced inflammatory response at 4 and 8 weeks compared to F-HADM. Both H-HADM and F-HADM demonstrate similar amounts of vascular ingrowth.

Non-invasive measurement of intra-abdominal pressure: a preliminary study

The importance of measuring intra-abdominal pressure (IAP) has increased since the negative effects of sustained increased IAP, also known as intra-abdominal hypertension (IAH), have become known. The relation between IAP and abdominal wall tension has been included in several reports. We have developed a device to measure abdominal wall tension by measuring force and distance. This device enables us to investigate the correlation between the abdominal wall tension and IAP. The abdomens of two corpses (one female, one male) were insufflated with air. IAP was increased and measured at intervals by means of a laparoscopic set-up. Abdominal tension was measured at seven points on the abdominal wall at each interval. Pearson's correlation coefficients were used to determine the relationship between IAP and tension for each point measured. ANOVA was used to assess relations between measured tensions versus applied pressure, locations and subjects. In both corpses, all points showed significant (p < 0.001) correlations between IAP and abdominal wall tension. The points along the mid transverse plane appear to be more similar compared to more cranial and caudal points. We have assessed the feasibility of a device that non-invasively can track changes in IAP. Measurements performed with the device are preliminary results, and further investigation is needed.

Laparoscopic versus open ventral hernia repairs: 5 year recurrence rates

BACKGROUND

Current studies with 2-3 year follow-up favor laparoscopic ventral hernia repair due to lower recurrence rates, fewer wound infections, and shorter hospital stays. There is scant data in the literature for this group of patients regarding longer follow-up. This study compares the actual 5 year recurrence rates of laparoscopic versus open techniques and determines factors that may affect recurrence.

METHODS

A retrospective analysis of ventral hernia repairs at a tertiary center between January 1996 and December 2001 was performed. In this era, the method of repair often depended on which surgeon evaluated the patient. All patients were followed for a minimum of 5 years (median 7.5 years). Demographic and clinical parameters were analyzed using Kaplan-Meier analyses and the multivariate Cox proportional hazard model.

RESULTS

Of 331 patients, 119 underwent laparoscopic ventral hernia repair (LAP), 106 open hernia repair with mesh (O-M), 86 open suture repair (O-S), and 20 laparoscopic converted to open (LCO). Statistical analyses showed equal parameters among groups except defect sizes (mean +/- standard error on the mean [SEM]): LAP (9.8 +/- 1.2 cm), O-M (11.2 +/- 3.3 cm), LCO (16.6 +/- 5.4 cm) versus O-S (4.6 +/- 1.6 cm) (p < 0.02). Actual recurrence rates at 1 and 5 years were LAP (15% and 29%), O-M (11% and 28%), O-S (10% and 19%), and LCO (35% and 60%). Multivariate analysis identified larger defects to have higher recurrence rates, particularly in the O-S group (p < 0.02). With the exception of the LCO group, surgical technique did not predict recurrence, nor did body mass index, diabetes, smoking, or use of tacks versus sutures.

CONCLUSION

This is the first study to compare 5 year actual recurrence rates between laparoscopic and open ventral hernia repairs. Contrary to prior reports, our longer-term data indicates similar recurrence rates, except for higher rates in the laparoscopic converted to open group. Due to the continued recurrences over the period studied, longer-term follow-up is necessary to appreciate the true rate of hernia recurrence.