Prospective, multicenter study of P4HB (Phasix™) mesh for hernia repair in cohort at risk for complications: 3-Year follow-up

Citric Acid: A Nexus Between Cellular Mechanisms and Biomaterial Innovations

Citrate-based biodegradable polymers have emerged as a distinctive biomaterial platform with tremendous potential for diverse medical applications. By harnessing their versatile chemistry, these polymers exhibit a wide range of material and bioactive properties, enabling them to regulate cell metabolism and stem cell differentiation through energy metabolism, metabonegenesis, angiogenesis, and immunomodulation. Moreover, the recent US Food and Drug Administration (FDA) clearance of the biodegradable poly(octamethylene citrate) (POC)/hydroxyapatite-based orthopedic fixation devices represents a translational research milestone for biomaterial science. POC joins a short list of biodegradable synthetic polymers that have ever been authorized by the FDA for use in humans. The clinical success of POC has sparked enthusiasm and accelerated the development of next-generation citrate-based biomaterials. This review presents a comprehensive, forward-thinking discussion on the pivotal role of citrate chemistry and metabolism in various tissue regeneration and on the development of functional citrate-based metabotissugenic biomaterials for regenerative engineering applications.

Missing the Mark: Evaluating the Validity of the Ventral Hernia Screen in Detecting Recurrence

PURPOSE

Hernia recurrence is a primary metric in evaluating the success of ventral hernia repair (VHR). Current screening methods for hernia recurrence, including the validated Ventral Hernia Screening (VHS) questionnaire, have not yet been critically evaluated. The purpose of this study was to evaluate the predictive value of the VHS for hernia recurrence.

METHODS

This is a retrospective cohort study of adult patients who underwent primary VHR utilizing poly-4-hydroxybutyrate mesh at a single-institution from January 2016 to December 2021 who completed at least one VHS during their postoperative follow-up. All patients who screened positive underwent follow-up diagnostic computed tomography or physical examination for confirmation of hernia recurrence. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were assessed for each item and the VHS as a whole.

RESULTS

A total of 68 patients who completed 119 VHS questionnaires were included. The median time to VHS administration was 3.6 years (range .8-6.3 years). The VHS tool had a sensitivity of 40.0%, specificity of 71.1%, PPV of 5.7%, and NPV of 96.4%. Individual items of the VHS also produced poor screening effects, with sensitivities between 20 and 40%, specificities between 79 and 97%, PPVs between 4 and 25%, and NPVs from 95 to 97%.

CONCLUSION

The VHS was a poor positive predictive tool for hernia recurrence, with both a low PPV and sensitivity. Many patients may be unaware of when they truly have hernia recurrence in the long term. More rigorous tools need to be developed to monitor recurrence following VHR.

Robotic transversus abdominis release (TAR) for ventral hernia repairs is associated with low surgical site occurrence rates and length of stay despite increasing modifiable comorbidities

PURPOSE

Modifiable comorbidities (MCMs) have previously been shown to complicate postoperative wound healing occasionally leading to surgeon hesitancy to repair ventral hernias prior to preoperative optimization of comorbidities. This study describes the effects of MCMs on surgical site occurrences (SSOs) and hospital length of stay (LOS) following robotic transversus abdominis release (TAR) with poly-4-hydroxybutyrate (P4HB) resorbable biosynthetic mesh retromuscular sublay for ventral hernia repair in patients who had not undergone preoperative optimization.

METHODS

A single-surgeon retrospective review was performed for patients who underwent the robotic TAR procedure with P4HB mesh between January 2015 and May 2022. Patients were stratified by the amount of MCMs present: 0, 1, or 2 + . MCMs included obesity, diabetes, and current tobacco use. Patient data was analyzed for the first 60 days following their operation. Primary outcomes included 60-day SSO rates and hospital LOS.

RESULTS

Three hundred and thirty-four subjects met the inclusion criteria for SSO and prolonged LOS analysis. 16.8% had no MCM, 56.1% had 1 MCM, and 27% had 2 + MCMs. No significant difference in SSO was seen between the 3 groups; however, having 2 + MCMs was significantly associated with increased odds of SSO (odds ratio 3.25, P = .019). When the groups were broken down, only having a history of diabetes plus obesity was associated with significantly increased odds of SSO (odds ratio 3.54, P = .02). No group showed significantly increased odds of prolonged LOS.

CONCLUSION

2 + MCMs significantly increase the odds of SSO, specifically in patients who have a history of diabetes and obesity. However, the presence of any number of MCMs was not associated with increased odds of prolonged LOS.

Five-Year Follow-Up of a Slowly Resorbable Biosynthetic P4HB Mesh (Phasix) in VHWG Grade 3 Incisional Hernia Repair

Objective

To assess the 5-year recurrence rate of incisional hernia repair in Ventral Hernia Working Group (VHWG) 3 hernia with a slowly resorbable mesh.

Summary Background Data

Incisional hernia recurs frequently after initial repair. In potentially contaminated hernia, recurrences rise to 40%. Recently, the biosynthetic Phasix mesh has been developed that is resorbed in 12-18 months. Resorbable meshes might be a solution for incisional hernia repair to decrease short- and long-term (mesh) complications. However, long-term outcomes after resorption are scarce.

Methods

Patients with VHWG grade 3 incisional midline hernia, who participated in the Phasix trial (Clinilcaltrials.gov: NCT02720042) were included by means of physical examination and computed tomography (CT). Primary outcome was hernia recurrence; secondary outcomes comprised of long-term mesh complications, reoperations, and abdominal wall pain [visual analogue score (VAS): 0-10].

Results

In total, 61/84 (72.6%) patients were seen. Median follow-up time was 60.0 [interquartile range (IQR): 55-64] months. CT scan was made in 39 patients (68.4%). A recurrence rate of 15.9% (95% confidence interval: 6.9-24.8) was calculated after 5 years. Four new recurrences (6.6%) were found between 2 and 5 years. Two were asymptomatic. In total, 13/84 recurrences were found. No long-term mesh complications and/or interventions occurred. VAS scores were 0 (IQR: 0-2).

Conclusions

Hernia repair with Phasix mesh in high-risk patients (VHWG 3, body mass index >28) demonstrated a recurrence rate of 15.9%, low pain scores, no mesh-related complications or reoperations for chronic pain between the 2- and 5-year follow-up. Four new recurrences occurred, 2 were asymptomatic. The poly-4-hydroxybutyrate mesh is a safe mesh for hernia repair in VHWG 3 patients, which avoids long-term mesh complications like pain and mesh infection.

Slowly absorbable mesh in sublay ventral hernia repair in contaminated fields

BACKGROUND

In the past years, there has been increasing evidence that supports the use of permanent mesh in contaminated wounds. Given this increased evidence, the indications to opt for slowly absorbable "biosynthetic" prostheses have been questioned. To address this, we compared the outcomes of slowly absorbable mesh in contaminated cases in a well-matched multicentric cohort.

METHODS

The Abdominal Core Health Quality Collaborative (ACHQC) database was queried for patients undergoing elective ventral hernia repair in Centers for Disease Control (CDC)-III operations (2013-2022). We compared demographics, hernia characteristics, and postoperative outcomes among types of mesh. We used propensity score matching to adjust for sex, diabetes, body mass index, smoking status, and operative time between mesh groups. Patients within other CDC classes and those with mesh positioned elsewhere than retro-rectus/preperitoneal space were excluded.

RESULTS

A total of 760 patients were included in the analysis. Slowly absorbable synthetic mesh (SA) was utilized in only 7% of the cases, while permanent (P) and biologic (B) mesh in 77% and 16%, respectively. After matching, 255 patients were studied. There was no difference in surgical site occurrence (8% SA, 16% P, 10% B, p = 0.27), surgical site infection (20% SA, 17% P, 12% B p = 0.54), surgical site occurrence requiring intervention (18% SA, 13% P, 14% B p = 0.72), readmission (12% SA, 14% P, 12% B, p = 0.90), or reoperation (8% SA, 2% P, 4% B, p = 0.14) at 30 days. In patients with 1-year follow-up, there was no difference in recurrence among groups (20% SA, 26% P, 24% B p = 0.90).

CONCLUSION

Based on our findings, SA has comparable outcomes to other types of mesh, particularly when an optimal retro-rectus repair is performed.

Poly-4-hydroxybutyrate Mesh for Ventral Hernia Repairs: A Single-Surgeon Experience

Background

Poly-4-hydroxybutyrate (P4HB) (Phasix) biosynthetic mesh was recently introduced as an alternative to synthetic and biologic meshes for ventral hernia repair (VHR). However, outcomes data are limited. This study aims to analyze outcomes of VHR with P4HB mesh and identify predictors of postoperative outcomes.

Methods

We performed a retrospective study of adults who underwent open VHR with P4HB by the senior author from 2014 to 2020 with >12 months' follow-up. Subgroup comparisons and multivariate logistic regression were performed.

Results

Inclusion criteria were met by 169 patients with a median of 15 months of follow-up. Overall, 21.9% had surgical site occurrences, 17.8% required reoperation, and 4.7% had recurrences. Patients with prior VHR (47.9%) experienced similar outcomes to those without. Patients with prior mesh infection (18.3%) had higher rates of postoperative mesh infection (6.5% vs 0.7%; P = .029) but did not have higher rates of reoperation. Retrorectus repairs (45.5%) had similar outcomes to onlay repairs (54.5%). Recurrence risk was increased by hypertension (odds ratio [OR] = 13.64; P = .046), immunosuppression (OR = 42.57; P = .004), and history of prior VHR (OR = 20.20; P = .014).

Conclusions

This study aimed to analyze outcomes of VHR augmented with P4HB mesh through retrospective review. VHR with P4HB mesh produces acceptable recurrence rates with favorable complication risks compared with biologic and synthetic meshes. Predictors of recurrence include a history of prior hernia repair, hypertension, and immunosuppression. A history of prior mesh infection seems to place patients at risk for developing subsequent infection but did not increase need for reoperation.

Modifiable comorbidities impact on ventral hernia recurrence following robotic abdominal wall reconstruction using resorbable biosynthetic mesh: 36-month follow-up

Background

There is an ongoing debate on the role of comorbidities in hernia outcomes, particularly with minimally invasive approaches. This study evaluated the impact of modifiable comorbidities (MCMs) on 36-month hernia recurrence rates after robotic transversus abdominis release (TAR) with resorbable biosynthetic mesh underlay for primary ventral hernia repair.

Methods

A review of medical records for patients who underwent the robotic TAR procedure between January 2015 and May 2022 performed by a single surgeon was conducted. Patients were separated into three groups: those with 0, 1, and 2+ MCMs, followed by a breakdown of comorbidity types and combinations of comorbidities. MCMs included obesity, diabetes, and tobacco use. The primary outcomes included hernia recurrence at 36 months and the time between surgery and recurrence.

Results

175 patients met the inclusion criteria, with a mean hernia diameter of 12.9 ± 5.4 cm and a mean BMI of 34 ± 8 kg/m2. 9.7 % of patients experienced hernia recurrence at 36-month follow-up. No significant difference in the recurrence rate and length of time between surgery and recurrence was observed between the groups (p = .265 and p = .283, respectively). No group, single comorbidity, or a combination of comorbidities was found to have significantly increased odds of recurrence at 36 months.

Conclusion

The presence of MCMs, either alone or in combination with another, did not significantly increase the odds of hernia recurrence at 36 months following ventral hernia repair using this approach. Future studies with larger sample sizes and multiple surgeons are needed to corroborate this data.

Key message

Modifiable comorbidities have previously been shown to increase the risk of hernia recurrence after ventral hernia repair. Our study found relatively low rates of hernia recurrence and no significantly increased odds of recurrence among different comorbid groups at 36-month follow-up following robotic transversus abdominis release with resorbable biosynthetic mesh underlay.

Fully resorbable poly-4-hydroxybutyrate (P4HB) mesh for soft tissue repair and reconstruction: A scoping review

Background

Poly-4-hydroxybutyrate (P4HB) is a fully resorbable, biologically-produced polymer with a strength and flexibility comparable to permanent synthetic polymers. The objective was to identify/summarize all peer-reviewed publications involving P4HB mesh.

Methods

A scoping review was conducted within PubMed and included articles published through October 2022.

Results

A total of n = 79 studies were identified (n = 12 in vitro/bench; n = 14 preclinical; n = 6 commentaries; n = 50 clinical). Of the clinical studies, n = 40 reported results applicable to hernia and n = 10 to plastic/reconstructive surgery and involved patients of all Centers for Disease Control (CDC) wound classes and Ventral Hernia Working Group (VHWG) grades.

Conclusion

P4HB mesh provides long-term hernia repair strength and exhibits promising clinical outcomes beyond its resorption period. Future studies should include randomized controlled trials comparing P4HB to other biomaterials, as well as optimal patient selection, operative technique, long-term outcomes, minimization of potential mesh-related complications, and potential contraindications/complications for P4HB in hernia/abdominal wall reconstruction.

Long-Term, Prospective, Multicenter Study of Poly-4-Hydroxybutyrate Mesh (Phasix Mesh) for Hernia Repair in Cohort at Risk for Complication: 60-Month Follow-Up

BACKGROUND

Long-term resorbable mesh represents a promising technology for ventral and incisional hernia repair (VIHR). This study evaluates poly-4-hydroxybutyrate mesh (P4HB; Phasix Mesh) among comorbid patients with CDC class I wounds.

STUDY DESIGN

This prospective, multi-institutional study evaluated P4HB VIHR in comorbid patients with CDC class I wounds. Primary outcomes included hernia recurrence and surgical site infection. Secondary outcomes included pain, device-related adverse events, quality of life, reoperation, procedure time, and length of stay. Evaluations were scheduled at 1, 3, 6, 12, 18, 24, 30, 36, and 60 months. A time-to-event analysis (Kaplan-Meier) was performed for primary outcomes; secondary outcomes were reported as descriptive statistics.

RESULTS

A total of 121 patients (46 male, 75 female) 54.7 ± 12.0 years old with a BMI of 32.2 ± 4.5 kg/m 2 underwent VIHR with P4HB Mesh (mean ± SD). Fifty-four patients (44.6%) completed the 60-month follow-up. Primary outcomes (Kaplan-Meier estimates at 60 months) included recurrence (22.0 ± 4.5%; 95% CI 11.7% to 29.4%) and surgical site infection (10.1 ± 2.8%; 95% CI 3.3 to 14.0). Secondary outcomes included seroma requiring intervention (n = 9), procedure time (167.9 ± 82.5 minutes), length of stay (5.3 ± 5.3 days), reoperation (18 of 121, 14.9%), visual analogue scale-pain (change from baseline -3.16 ± 3.35 cm at 60 months; n = 52), and Carolinas Comfort Total Score (change from baseline -24.3 ± 21.4 at 60 months; n = 52).

CONCLUSIONS

Five-year outcomes after VIHR with P4HB mesh were associated with infrequent complications and durable hernia repair outcomes. This study provides a framework for anticipated long-term hernia repair outcomes when using P4HB mesh.

Ventral hernia repair in high-risk patients and contaminated fields using a single mesh: proportional meta-analysis

PURPOSE

The use of mesh is a common practice in ventral hernia repair (VHR). Lack of consensus on which prosthetic material works better in different settings remains. This meta-analysis aims to summarize the available evidence on hernia recurrence and complications after repair with synthetic, biologic, or biosynthetic/bioabsorbable meshes in hernias grade 2-3 of the Ventral Hernia Working Group modified classification.

METHODS

A literature search was conducted in January 2021 using Web of Science (WoS), Scopus, and MEDLINE (via PubMed) databases. Randomized Controlled Trials (RCTs) and observational studies with adult patients undergoing VHR with either synthetic, biologic, or biosynthetic/bioabsorbable mesh were included. Outcomes were hernia recurrence, Surgical Site Occurrence (SSO), Surgical Site Infection (SSI), 30 days re-intervention, and infected mesh removal. Random-effects meta-analyses of pooled proportions were performed. Quality of the studies was assessed, and heterogeneity was explored through sensitivity analyses.

RESULTS

25 articles were eligible for inclusion. Mean age ranged from 47 to 64 years and participants' follow-up ranged from 1 to 36 months. Biosynthetic/bioabsorbable mesh reported a 9% (95% CI 2-19%) rate of hernia recurrence, lower than synthetic and biologic meshes. Biosynthetic/bioabsorbable mesh repair also showed a lower incidence of SSI, with a 14% (95% CI 6-24%) rate, and there was no evidence of infected mesh removal. Rates of seroma were similar for the different materials.

CONCLUSIONS

This meta-analysis did not show meaningful differences among materials. However, the best proportions towards lower recurrence and complication rates after grade 2-3 VHR were after using biosynthetic/slowly absorbable mesh reinforcement. These results should be taken with caution, as head-to-head comparative studies between biosynthetic and synthetic/biologic meshes are lacking. Although, biosynthetic/bioabsorbable materials could be considered an alternative to synthetic and biologic mesh reinforcement in these settings.

Incisional hernia repair with a slowly absorbable P4HB mesh: what happens after the mesh disappears? A retrospective longitudinal clinical study

PURPOSE

To analyze the incisional hernia recurrence rate at a long-term follow-up using a biosynthetic long-term absorbable mesh in patients with a higher risk of surgical infection in a contaminated surgical field.

METHODS

This was a retrospective multicentric study. All patients undergoing incisional hernia repair between 2016 and 2018 at 6 participating university centers were included. Patients were classified according to the Ventral Hernia Working Group (VHWG). All consecutive patients who underwent abdominal wall repair using biosynthetic long-term absorbable mesh (Phasix^®) in contaminated fields (grade 3 and 4 of the VHWG classification) were included. Patients were followed-up until September 2021. Preoperative, operative, and postoperative data were collected. All patients' surgical site infections (SSIs) and surgical site occurrences (SSOs) were recorded. The primary outcome of interest was the clinical incisional hernia recurrence rate.

RESULTS

One hundred and eight patients were included: 77 with VHWG grade 3 (71.3%) and 31 with VHWG grade 4 (28.7%). Median time follow-up was 41 months [24; 63]. Twenty-four patients had clinical recurrence during the follow-up (22.2%). The SSI and SSO rates were 24.1% and 36.1%, respectively. On multivariate analysis, risk factors for incisional hernia recurrence were previous recurrence, mesh location, and postoperative enterocutaneous fistula.

CONCLUSIONS

At the 3 year follow-up, the recurrence rate with a biosynthetic absorbable mesh (Phasix^®) for incisional hernia repair in high-risk patients (VHWG grade 3 and 4) seemed to be suitable (22.2%). Most complications occurred in the first year, and SSI and SSO rates were low despite high-risk VHWG grading.

Clinical outcomes of open abdominal wall reconstruction with the use of a polypropylene reinforced tissue matrix: a multicenter retrospective study

Objective

To assess mesh behaviour and clinical outcomes of open complex abdominal wall reconstruction (CAWR) with the use of a polypropylene reinforced tissue matrix.

Methods

A multicenter retrospective study of adult patients who underwent open CAWR with the use of a permanent polypropylene reinforced tissue matrix (OviTex^®) between June 2019 and January 2021.

Results

Fifty-five consecutive patients from four hospitals in the Netherlands were analysed; 46 patients with a ventral hernia and 9 patients with an open abdomen. Most patients with a ventral hernia had one or more complicating comorbidities (91.3%) and one or more complicating hernia characteristics (95.7%). Most procedures were performed in a (clean) contaminated surgical field (69.6% CDC 2–4; 41.3% CDC 3–4). All nine patients with an open abdomen underwent semi-emergent surgery. Twelve out of 46 patients with a ventral hernia (26.1%) and 4 of 9 patients with an open abdomen (44.4%) developed a postoperative surgical site infection that made direct contact with the mesh as confirmed on computed tomography (CT), suspicious of mesh infection. No patient needed mesh explantation for persistent infection of the mesh. During a median follow-up of 13 months, 4 of 46 ventral hernia patients (8.7%) developed a CT confirmed hernia recurrence.

Conclusion

Polypropylene reinforced tissue matrix can withstand infectious complications and provides acceptable mid-term recurrence rates in this retrospective study on open complex abdominal wall reconstructions. Longer follow-up data from prospective studies are required to determine further risk of hernia recurrence.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10029-022-02604-y.

A prospective, multicenter trial of a long-term bioabsorbable mesh with Sepra technology in cohort of challenging laparoscopic ventral or incisional hernia repairs (ATLAS trial)

BACKGROUND

This prospective, multicenter, single-arm, open-label study evaluated P4HB-ST mesh in laparoscopic ventral or incisional hernia repair (LVIHR) in patients with Class I (clean) wounds at high risk for Surgical Site Occurrence (SSO).

METHODS

Primary endpoint was SSO requiring intervention <45 days. Secondary endpoints included: surgical procedure time, length of stay, SSO >45 days, hernia recurrence, device-related adverse events, reoperation, and Quality of Life at 1, 3, 6, 12, 18, and 24-months.

RESULTS

120 patients (52.5% male), mean age of 55.0 ± 14.9 years, and BMI of 33.2 ± 4.5 kg/m2 received P4HB-ST mesh. Patient-reported comorbid conditions included: obesity (86.7%), active smoker (45.0%), COPD (5.0%), diabetes (16.7%), immunosuppression (2.5%), coronary artery disease (7.5%), chronic corticosteroid use (2.5%), hypoalbuminemia (0.8%), advanced age (10.0%), and renal insufficiency (0.8%). Hernia types were primary ventral (44.2%), primary incisional (37.5%), recurrent ventral (5.8%), and recurrent incisional (12.5%). Patients underwent LVIHR in laparoscopic (55.8%) or robotic-assisted cases (44.2%), mean defect size 15.7 ± 28.3 cm2, mean procedure time 85.9 ± 43.0 min, and mean length of stay 1.0 ± 1.4 days. There were no SSOs requiring intervention beyond 45 days, n = 38 (31.7%) recurrences, n = 22 (18.3%) reoperations, and n = 2 (1.7%) device-related adverse events (excluding recurrence).

CONCLUSION

P4HB-ST mesh demonstrated low rates of SSO and device-related complications, with improved quality of life scores, and reoperation rate comparable to other published studies. Recurrence rate was higher than expected at 31.7%. However, when analyzed by hernia defect size, recurrence was disproportionately high in defects ≥7.1 cm2 (43.3%) compared to defects <7.1 cm2 (18.6%). Thus, in LVIHR, P4HB-ST may be better suited for small defects. Caution is warranted when utilizing P4HB-ST in laparoscopic IPOM repair of larger defects until additional studies can further investigate outcomes.

Long-term outcome of absorbable synthetic mesh in clean ventral hernia repairs

BACKGROUND

There are many materials available for the reinforcement of complex abdominal wall reconstruction, including permanent synthetic, biologic, and absorbable synthetic meshes. The recurrence rate of complex hernia repairs beyond 5 years has not been reported. We hypothesized that the use of absorbable synthetic mesh in clean wounds would yield favorable long-term outcomes.

STUDY DESIGN

Patients who underwent open complex ventral hernia repair with clean wounds (CDC class 1) using absorbable synthetic mesh (Bio-A, Gore, Flagstaff, AZ) in the retrorectus position were retrospectively reviewed. Chart review and a validated telephone questionnaire to screen for recurrence were utilized to evaluate and document hernia recurrence.

RESULTS

A total of 49 patients were included in this study. Patients were followed for recurrences for up to 105 months, with a mean follow-up time of 62.4 months (5.2 years). The total number of midline hernia recurrence was 7 out of the original 49 patients (14%). The mean and median recurrence time are 37.4 and 38.8 months, respectively. Kaplan-Meier survival analysis estimated hernia recurrence rate as 2%, 4.6%, 7.1%, 12%, 15%, and 18% at 12, 24, 36, 48, 60, and 72 months, respectively.

CONCLUSION

The use of absorbable synthetic mesh in clean wound ventral hernia repair resulted in favorable long-term recurrence rates. The recurrence rate of absorbable synthetic mesh is similar to that of permanent synthetic mesh, which gives a viable option for patients in whom permanent synthetic mesh is not an option.

Nationwide Readmissions Analysis of Minimally Invasive Versus Open Ventral Hernia Repair: A Retrospective Population-Based Study

INTRODUCTION

Minimally invasive ventral hernia repair (MISVHR) has been performed for almost 30 years; recently, there has been an accelerated adoption of the robotic platform leading to renewed comparisons to open ventral hernia repair (OVHR). The present study evaluates patterns and outcomes of readmissions for MISVHR and OVHR patients.

METHODS

The Nationwide Readmissions Database (NRD) was queried for patients undergoing OVHR and MISVHR from 2016 to 2018. Demographic characteristics, complications, and 90-day readmissions were determined. A subgroup analysis was performed to compare robotic ventral hernia repair (RVHR) vs laparoscopic hernia repair (LVHR). Standard statistical methods and logistic regression were used.

RESULTS

Over the 3-year period, there were 25 795 MISVHR and 180 635 OVHR admissions. Minimally invasive ventral hernia repair was associated with a lower rate of 90-day readmission (11.3% vs 17.3%, P < .01), length of stay (LOS) (4.0 vs 7.9 days, P < .01), and hospital charges ($68,240 ± 75 680 vs $87,701 ± 73 165, P < .01), which remained true when elective and non-elective repairs were evaluated independently. Postoperative infection was the most common reason for readmission but was less common in the MISVHR group (8.4% vs 16.8%, P < .01). Robotic ventral hernia repair increased over the 3-year period and was associated with decreased LOS (3.7 vs 4.1 days, P < .01) and comparable readmissions (11.3% vs 11.2%, P = .74) to LVHR, but was nearly $20,000 more expensive. In logistic regression, OVHR, non-elective operation, urban-teaching hospital, increased LOS, comorbidities, and payer type were predictive of readmission.

CONCLUSIONS

Open ventral hernia repair was associated with increased LOS and increased readmissions compared to MISVHR. Robotic ventral hernia repair had comparable readmissions and decreased LOS to LVHR, but it was more expensive.

A Prospective, Single Arm, Multi-Center Study Evaluating the Clinical Outcomes of Ventral Hernias Treated with OviTex® 1S Permanent Reinforced Tissue Matrix: The BRAVO Study 12-Month Analysis

BACKGROUND

Conflicting results from previous studies have led to dissent over whether surgical mesh is safe and effective in ventral hernia repair. A newer class of mesh known as a reinforced tissue matrix, combining a biologic scaffold and minimal polymer reinforcement, offers promise in reducing inflammatory response and increasing abdominal wall support. This study sought to assess the clinical utility of a reinforced tissue matrix (OviTex) in ventral hernia repair 12 months after implantation.

METHODS

This is a prospective, single-arm, multi-center study to evaluate the clinical performance of OviTex^® 1S Permanent (OviTex) in the repair of primary or recurrent ventral hernias (VH) in consecutive patients (ClinicalTrials.gov/NCT03074474). The rate of surgical site occurrences (SSOs) was evaluated 90 days post-surgery as the primary endpoint. Hernia recurrence and the incidence of postoperative events were evaluated between three and 12 months as secondary endpoints. The incidence of other complications and patient-reported outcomes were also recorded.

RESULTS

Ninety-two (92) patients were enrolled in the study, of whom seventy-six (76) reached the 12-month follow-up. All patients were at least 18 years of age with a BMI of <40 kg/m². Hernia defects were <20 × 20 cm, classified as class I-III according to the CDC wound classification system. Of the 76 patients who reached 12-month follow-up, twenty-six (34%) had previous VH repairs and thirteen (17%) had previous surgical infection. Sixty (79%) had factors known to increase the risk of recurrence. Twenty patients (26%) experienced SSOs, with ten (13%) requiring procedural intervention. Two of the 75 patients (2.7%) experienced a recurrence.

CONCLUSIONS

The low rate of hernia recurrence and SSOs requiring intervention illustrates the potential that reinforced tissue matrices, and OviTex 1S, in particular, have to improve outcomes in VH repairs. Follow-up to 24 months is ongoing.

Outcomes of posterior component separation with transversus abdominis release (TAR) in large and other complex ventral hernias: a single-surgeon experience

PURPOSE

Over the last years, great advances in the repair of abdominal wall hernias have dramatically improved patients' outcomes. Especially for large and other complex ventral hernias, the application of component separation techniques has been a landmark in their successful management. The aim of this study is to present our experience with the posterior component separation with transversus abdominis release (TAR) in patients with these demanding ventral hernias.

METHODS

A retrospective analysis of prospectively collected data of all patients who underwent elective ventral hernia repair with TAR between January 2016 and December 2019 was performed. Preoperative, intraoperative, and postoperative data were analyzed.

RESULTS

A total of 125 patients with large and other complex ventral hernias were included in the final analysis. More than 80% of patients had one or more comorbidities. Of all patients, 116 (92.8%) had a history of previous abdominal surgery, 27 (21.6%) had a history of SSI and nine (7.2%) had active fistulas. Postoperatively, SSOs were presented in 11 patients (8.8%), including three cases of SSI. Neither mesh infection occurred, nor mesh excision required. With a mean follow-up of 2.5 years, only one recurrence was observed.

CONCLUSIONS

With a wound complication rate of less than 9% and a recurrence rate of less than 1%, our results show that TAR is a reliable, safe and effective technique for the repair of massive and other complex ventral hernias. The combination of knowledge of the abdominal wall anatomy at a proficient level, proper training, and adoption of a strict prehabilitation program are considered prerequisites for the successful management of such demanding hernias.

A Polymer-Biologic Hybrid Hernia Construct: Review of Data and Early Experiences

Surgical mesh reinforcement of the human abdominal wall has been found to reduce the chance of recurrence in hernia repairs. While traditionally polymer meshes have been used in hernia repair, alternative mesh options have been engineered to prevent the inflammatory foreign body response invoked by polymers. A reinforced tissue matrix (RTM) mesh has been developed by embedding a polymer within a decellularized extracellular matrix. This combination has been attributed to the recruitment of host cells, a pro-healing response, and attenuation of the foreign body response. This has been observed to lead to the regeneration of functional tissue within the repair site that is reinforced by the polymer to offload abdominal pressures over time. This manuscript presents the review of OviTex, an RTM, in several types of hernia repair. The authors have found that the use of RTM in hernia repair is effective in preventing foreign body response, promoting wound healing, and providing reinforcement to lower the risk of hernia recurrence.

Outcomes of biosynthetic absorbable mesh use in high risk CDC Class I ventral hernia repair: a single surgeon series

PURPOSE

Biosynthetic absorbable meshes have emerged as suitable alternatives to permanent synthetic and biologic meshes in complex ventral hernia repair in contaminated wounds. Evidence regarding the use of these products in clean wounds is currently scant. This paper presents a large single surgeon series using GORE^®BIO-A^® (W.L. Gore & Associates, Newark, DE) (Bio-A) tissue reinforcement in high risk patients with predominantly CDC Class I wounds.

METHODS

Retrospective review of a prospectively maintained database of consecutive patients who underwent open ventral hernia repair with biosynthetic absorbable mesh was conducted. Ventral Hernia Working Group (VHWG) classification based on patient demographics and Centers for Disease Control (CDC) wound type were collected prospectively. All patients were followed up for a minimum of 12 months post-operatively.

RESULTS

155 patients were included with a mean post-operative follow up of 29 months (range 12-62 months). Mean age was 61.8 years with an average BMI of 33.5 kg/m². 147 patients (94.9%) were classified as VHWG 2 or 3 based on comorbidities or surgical field contamination. 69% (n = 107) of wounds were designated CDC Class I. Mean hernia size was 119.7cm² with recurrent defects comprising 32.3% (n = 50). Retrorectus mesh repair was achieved in 84.5% of patients (n  = 131). Post-operative wound events occurred in 19.3%. No mesh was explanted. Hernia recurrence rate was 9.0% with a mean time to recurrence of 14 months. There was no significant difference in recurrence rates between clean and contaminated wounds.

CONCLUSION

This study supports the use of Bio-A in high risk ventral hernias, demonstrating a safe and durable repair across all wound classes. Ongoing follow-up continues to monitor for late complications and recurrence.

An evaluation of clinical and quality of life outcomes after ventral hernia repair with poly-4-hydroxybutyrate mesh

PURPOSE

Despite continued efforts, recurrence after ventral hernia repair (VHR) remains a common problem. Biosynthetic Phasix^™ (Poly-4-Hydroxybutyrate, P4HB) mesh combines the durability of synthetic mesh with the bio-resistance of biologics. P4HB has shown promising early outcomes, but long-term data are lacking. We examine patients following VHR with P4HB with at least 3 years of follow-up to assess clinical and patient reported outcomes (PROs).

METHODS

Adult patients (≥ 18 years old) undergoing VHR with P4HB mesh between 10/2015 and 01/2018 by a single surgeon were retrospectively identified. Patients with < 36 months of follow-up were excluded unless they had a documented recurrence. Clinical outcomes and quality of life using the Hernia-Related Quality of Life Survey (HerQLes) were assessed.

RESULTS

Seventy-one patients were included with a median age and body mass index of 61.2 and 31 kg/m², respectively. Mesh was placed in the retromuscular (79%) and onlay (21%) planes with 1/3 of patients having hernias repaired in contaminated fields. There were no mesh infections, enterocutaneous fistulas, or mesh explantations. Nine patients (12.7%) developed recurrence at a median follow-up of 43.1 months [38.2-49.1]. Mesh plane, fixation technique, and Ventral Hernia Working Group were not associated with recurrence. Significant improvement in disease-specific PROs was observed and maintained at 3-year follow-up.

CONCLUSION

Longitudinal clinical and quality of life outcomes after clean and contaminated VHR with P4HB are limited. Here, we conclude that P4HB is an effective and versatile mesh option for use in abdominal wall reinforcement.