Slowly resorbable biosynthetic mesh: 2-year results in VHWG grade 3 hernia repair

The use of poly-4-hydroxybutyrate (P4HB, Phasix™) mesh in ventral hernia repair: a systematic review and meta-analysis

PURPOSE/BACKGROUND

Despite the growing use of bioabsorbable mesh in ventral hernia repairs (VHR), the evidence of its impact on patient outcomes remains limited. This study aims to investigate the efficacy and safety profile of poly-4-hydroxybutyrate (P4HB) mesh for ventral hernia repair through a systematic review and meta-analysis.

METHODS

A literature search of five databases (PubMed, Embase, Ovid, Medline, and Google Scholar) produced a list of publications that analyzed the use of P4HB mesh in ventral hernia repair in both clean and contaminated cases. The primary postoperative outcomes of hernia recurrence, surgical site infections (SSI), and any complications were analyzed through a pooled meta-analysis.

RESULTS

In our systematic review, 21 studies met the inclusion criteria with a total of 1858 patients (933 males and 925 females) and an average age of 56.8 years. The median follow-up ranged from 1.6 to 62.3 months. In our meta-analysis, the use of P4HB mesh in VHR in proportion of events demonstrated a recurrence rate of 9% [6%; 15%], SSI of 10% [6%; 16%] and 35% [9%; 42%] for rate of any complications. Sub-meta-analysis restricted to studies with follow up > 18 months continues to show low rates of recurrence of 9% (95%CI, 4-17%), SSI of 9% (95%CI, 4-16%), and 31% (95%CI, 23-41%) for any complications.

CONCLUSION

Our study demonstrates that the use of P4HB mesh is both safe and effective in ventral hernia repairs. When further analyzed past 18 months, the time where P4HB mesh fully resorbs, the rates of hernia recurrence, SSI, and any complications remain low of upwards of 5 years and comparable to the rates seen in synthetic and biologics in similar patient populations.

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.

A Review of Abdominal Meshes for Hernia Repair-Current Status and Emerging Solutions

Abdominal hernias are common issues in the clinical setting, burdening millions of patients worldwide. Associated with pain, decreased quality of life, and severe potential complications, abdominal wall hernias should be treated as soon as possible. Whether an open repair or laparoscopic surgical approach is tackled, mesh reinforcement is generally required to ensure a durable hernia repair. Over the years, numerous mesh products have been made available on the market and in clinical settings, yet each of the currently used meshes presents certain limitations that reflect on treatment outcomes. Thus, mesh development is still ongoing, and emerging solutions have reached various testing stages. In this regard, this paper aims to establish an up-to-date framework on abdominal meshes, briefly overviewing currently available solutions for hernia repair and discussing in detail the most recent advances in the field. Particularly, there are presented the developments in lightweight materials, meshes with improved attachment, antimicrobial fabrics, composite and hybrid textiles, and performant mesh designs, followed by a systematic review of recently completed clinical trials.

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.

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.

Biosynthetic meshes in contaminated fields: where are we now? A systematic review and meta-analysis in humans

PURPOSE

Selection of an appropriate mesh reinforcement for hernia repair in contaminated fields is a significant problem for surgeons. To date the proper mesh for contaminated fields has not been found. Biosynthetic meshes have emerged as new treatment option in contaminated fields. This study aims to evaluate the postoperative outcomes of biosynthetic meshes in contaminated fields.

METHODS

Systematic electronic search (PubMed, Medline, Embase, Scopus), according to PRISMA criteria, was performed. A literature search of scientific papers was performed by two reviewers until April 2021. Articles were chosen based on reference to biosynthetic meshes, their use in infected fields, and in human subjects. GRADE methodology and the modified Newcastle-Ottawa scale were used to assess the quality of studies. According to CDC-Centers for Disease Control classes patients were divided into two subgroups, group 1 (CDC class 2) and group 2 (CDC classes 3-4).

RESULTS

The research included 21 articles and 1619 patients were analyzed. Long-term follow-up showed a significant higher recurrence rate than short-term follow-up. P < 0.001. Meta-analysis of these studies showed that the SSI were significantly higher in CDC classes 3-4 than CDC class 2 (P < 0.01). No differences were found in SSO (P = 0.06) and recurrence (P = 0.37) rate among the two groups. Phasix™ was the most common mesh in 15 studies. The mean follow-up was 23.0 months. The surgical site infection (SSI) rate was 17.3%. The surgical site occurrence (SSO) rate was 32.4%. Recurrence rate was 11.5%.

CONCLUSION

This is the first systematic review and meta-analysis on the clinical outcomes of abdominal wall repair using biosynthetic mesh in contaminated-infected settings. The results show good results in patients at high risk of postoperative wound complications. The aim of this study is to add to the growing literature on biosynthetic mesh a picture of current literature evidence to help future researchers performing further studies on this topic.

Outcomes of biologic versus synthetic mesh in CDC class 3 and 4 open abdominal wall reconstruction

INTRODUCTION

Abdominal wall reconstruction (AWR) in a contaminated field is associated with an increased risk of wound complications, infection, and reoperation. The best method of repair and mesh choice in these operations have generated marked controversy. Our aim was to compare outcomes of patients who underwent AWR with biologic versus synthetic mesh in CDC class 3 and 4 wounds.

METHODS

A prospective, single-institution database was queried for AWR using biologic or synthetic mesh in CDC Class 3 and 4 wounds. Hernia recurrence and complications were measured. Multivariable logistic regression was performed to identify factors predicting both.

RESULTS

In total, 386 patients with contaminated wounds underwent AWR, 335 with biologic and 51 with synthetic mesh. Groups were similar in age, sex, BMI, and rate of diabetes. Biologic mesh patients had larger hernia defects (298 ± 233cm² vs. 208 ± 155cm²; p = 0.004) and a higher rate of recurrent hernias (72.2% vs 47.1%; p < 0.001), comorbidities(5.8 ± 2.7 vs. 4.2 ± 2.4, p < 0.01), and a nearly fivefold increase in Class 4 wounds (47.8% vs. 9.8%, p < 0.001), while fascial closure trended to being less common (90.7% vs 96.1%; p = 0.078). Hernia recurrence was comparable between biologic and synthetic mesh (10.4% vs. 17.6%, p = 0.132). Wound complication rates were similar (36.1% vs. 33.3%, p = 0.699), but synthetic mesh had higher rates of mesh infection (1.2% vs 11.8%; p < 0.001) and infection-related resection (0% vs 7.8%, p < 0.001), with 66% of those synthetic mesh infections requiring excision. On logistic regression, wound complications (OR 5.96 [CI 1.60-22.17]; p = 0.008) and bridging mesh (OR 13.10 [CI 2.71-63.42];p = 0.030) predicted of hernia recurrence (p < 0.05), while synthetic mesh (OR 18.6 [CI 2.35-260.4] p = 0.012) and wound complications (OR 20.6 [CI 3.15-417.7] p = 0.008) predicted mesh infection.

CONCLUSIONS

Wound complications in AWR with CDC class 3 and 4 wounds significantly increased mesh infection and hernia recurrence; failure to achieve fascial closure also increased hernia recurrence. Use of synthetic versus biologic mesh increased the mesh infection rate by 18.6 times.

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.