Biologic mesh in ventral hernia repair: Outcomes, recurrence, and charge analysis

Comparison of short-term clinical efficacy and safety between biological and synthetic meshes in laparoscopic hiatal hernia repair: a single-center randomized controlled trial

BACKGROUND

The optimal choice of mesh material in laparoscopic hiatal hernia repair (LHHR) is debated. This study aimed to compare the short-term clinical efficacy and safety of biological versus synthetic meshes in LHHR.

METHODS

In a prospective, single-center randomized controlled trial conducted from January 2020 to December 2022, 124 patients undergoing LHHR were enrolled and randomly assigned to either the biological mesh group (n = 62) or the synthetic mesh group (n = 62). The biological mesh group received non-crosslinked biological mesh, while the synthetic mesh group received polypropylene anti-adhesion mesh for hiatal closure reinforcement. Randomization was computer-generated. Baseline characteristics were collected, and patients were followed up at 6, 12, and 18 months postoperatively through telephone interviews or outpatient visits. The primary outcome was the recurrence rate of hiatal hernia, assessed by gastroscopy and upper gastrointestinal contrast radiography. Secondary outcomes included symptom improvement evaluated using the Visual Analog Scale (VAS) and the Short Form-36 (SF-36) Health Survey Questionnaire, as well as quality of life improvements. The safety of mesh was assessed by recording mesh-related complications.

RESULTS

Baseline characteristics were comparable between the two groups. At 18 months, the recurrence rate was 1.92% in the synthetic mesh group and 9.26% in the biological mesh group (P = 0.225). At 6 months, the biological mesh group reported significantly less early satiety compared to the synthetic mesh group (0.35 ± 1.09 vs. 0.95 ± 1.99; P = 0.046). Conversely, at 18 months, early satiety was lower in the synthetic mesh group compared to the biological mesh group (0.31 ± 1.35 vs. 1.04 ± 2.21; P = 0.043). No significant differences were observed between the groups for other symptoms or SF-36 domains at any time point (all P > 0.05). Both groups showed significant improvements in some symptoms and quality of life from preoperative to postoperative assessments (P < 0.05). No mesh-related complications were reported in either group throughout the 18-month follow-up period.

CONCLUSIONS

Both biological and synthetic meshes are effective and safe for use in LHHR, demonstrating similar recurrence rates and improvements in symptoms and quality of life over an 18-month period. The choice of mesh may influence early satiety at different postoperative intervals, suggesting that individualized mesh selection based on patient-specific factors may enhance postoperative outcomes.

Outcomes of synthetic and biologic mesh in abdominal wall reconstruction: A propensity-matched analysis in Centers for Disease Control and Prevention class 1 and 2 wounds

INTRODUCTION

The choice of biologic compared with synthetic mesh in abdominal wall reconstruction remains controversial, especially in Centers for Disease Control and Prevention class 1 and 2 wounds. This study evaluated wound complications and hernia recurrence with a 2:1 propensity-matched sample and extended follow-up.

METHODS AND PROCEDURES

A prospectively maintained abdominal wall reconstruction database was queried for patients undergoing open abdominal wall reconstruction using biologic or synthetic mesh in Centers for Disease Control and Prevention class 1 and 2 wounds. Patients receiving synthetic or biologic mesh were propensity score matched in a 2:1 fashion. Univariate, bivariate, and inferential analyses were conducted. Unless stated, data are reported as biologic compared with synthetic.

RESULTS

In total, 519 patients were compared, 173 with biologic and 346 with synthetic mesh. Defect size (215.2 ± 153.6 cm2 vs 251.5 ± 284.3 cm2), body mass index (33.6 ± 9 kg/m2 vs 34 ±17.7 kg/m2), and comorbidities were well matched (all P > .05). Although Centers for Disease Control and Prevention wound class was used in the match, it was significantly different between groups (Centers for Disease Control and Prevention 1:43.4% vs 81.2%, Centers for Disease Control and Prevention 2:56.6% vs 18.8%; P < .001). The rate of component separation (40.1% vs 44.2%; P = .397), fascial closure (97.7% vs 98.3%; P = .738), and panniculectomy (33.5% vs 29.2%; P = .315) were similar. Mesh size was also similar (816.4 ± 555.5 vs 892.2 ± 487.8 cm2; P = .112). Wound complications were equal, including wound breakdown (10.5% vs 7.5%; P = .315), wound cellulitis (5.2% vs 5.8%; P = .843), wound infection (7.5% vs 4.6%; P = .223), seroma requiring intervention (6.4% vs 7.8%; P = .597), and mesh infection (1.2% vs 0.9%; P > .999). The biologic group had an increased length of stay (6.8 ± 5.5 days vs 5.4 ± 2.3 days; P < .001) and greater hospital charges ($82,181 ± 50,356 vs $62,221 ± 26,817 USD; P < .001). Mean follow-up after biologic repair was longer (33.9 ± 36.6 months vs 23.3 ± 32.3 months; P < .001). Hernia recurrence between the biologic and synthetic groups was not significantly different (2.9% vs 1.4%; P = .313). On multivariable regression, wound complications were predictive of recurrence, and panniculectomy was predictive of wound complications.

CONCLUSION

In a 2:1 matched analysis of Centers for Disease Control and Prevention 1 and 2 wounds with nearly 3-years of follow-up, biologic and synthetic mesh had similar rates of wound complications and recurrence in abdominal wall reconstruction.

Onlay Resorbable Biosynthetic Versus Underlay Biologic Mesh Ventral Hernia Repair in Contaminated Fields

INTRODUCTION

Abdominal wall reconstruction (AWR) with ventral hernia repair (VHR) in the setting of contamination poses unique and controversial challenges. The purpose of this study was to examine the efficacy of onlay resorbable biosynthetic mesh against underlay biologic mesh in contaminated VHR with AWR.

METHODS

A single-center retrospective review from 2015 to 2021 was performed examining subjects who underwent VHR with AWR in contaminated fields (Centers for Disease Control wound class II-IV). A matched paired analysis based on age, body mass index, and Centers for Disease Control wound class was conducted among patients who utilized resorbable biosynthetic mesh in an onlay fashion and biologic mesh in an underlay fashion.

RESULTS

A total of 94 patients (47 per group) underwent VHR with AWR in contaminated fields. Patients who utilized biosynthetic mesh had an average defect size of 314.56 ± 214.65 cm2, required component separation (57.4%), and were often recurrent (61.7%). Majority of contamination were clean-contaminated (68.1%), followed by dirty/infected (19.1%), and contaminated (12.8%). Patients utilizing resorbable biosynthetic mesh experienced fewer surgical site occurrences (SSOs) (46.8% versus 72.3%, P < 0.05) and fewer SSO procedural interventions (19.1% versus 38.4%, P < 0.05). Patients with biosynthetic mesh had fewer hernia recurrences compared to biologic mesh use; however, was not statistically significant (14.9% versus 30.4%, P = 0.07), with a mean follow-up of 25.73 ± 18.66 mo.

CONCLUSIONS

Utilization of resorbable biosynthetic mesh may be preferable to biologic mesh in contaminated fields due to lower rates of SSOs and interventions, ultimately reducing the postoperative clinical and financial burden for this patient population.

Acellular dermal matrices in reconstructive surgery; history, current implications and future perspectives for surgeons

Large-scale defects of body in the reconstructive surgical practice, and the helplessness of their repair with autologous tissues, have been an important factor in the development of artificial biological products for the temporary, definitive, or staged repair of these defects. A major advance in the field of plastic and other reconstructive surgery in this regard has been the introduction and successful use of acellular dermal matrices (ADMs). In recent years, not only the type of tissue from which ADMs are produced, product range, diversity and areas of use have increased, but their use in reconstructive fields, especially in post oncologic breast surgery, has become highly regarded and this has favored ADMs to be a potential cornerstone in specific and well-defined surgical fields in future. It is essential that reconstructive surgeons become familiar with some of the ADM's as well as the advantages and limitations to their use. This review not only provides basic science and clinical evidence of the current use of ADMs in wide range of surgical fields but also targets to keep them as an important backdrop in the armamentarium of reconstructive surgeons. Brief considerations of possible future directions for ADMs are also conducted in the end.

Mesh exposure after ventral hernia repair with onlay biosynthetic mesh: a retrospective review of associated risk factors and management strategies

BACKGROUND

Although intraperitoneal and retromuscular mesh placement in ventral hernia repair (VHR) are associated with lower recurrence rates, the onlay plane remains a well-established option for certain clinical scenarios. A knowledge gap remains regarding resorbable biosynthetic onlay mesh and mesh exposure. We aim to determine exposure rate, risk factors, and treatment options.

STUDY DESIGN

A single-center, two-surgeon retrospective review was performed examining patients who underwent VHR with onlay, Poly-4-hydroxybutyrate (P4HB) mesh from 2015 to 2021. Demographics, operative characteristics, outcomes, and mesh exposure management were analyzed.

RESULTS

Of 346 patients, 15 (4.3%) experienced mesh exposure. The mean age was 53 years and BMI of 33.6 kg/m2. Patients were majority ASA class 3 (65%), female (64.2%), and averaged a defect size of 307.9 ± 235.2 cm2. Independent risk factors included diabetes (AOR = 4.3,CI 1.5-12.5;p < 0.005) and COPD (AOR = 5.2,CI 1.3-21.8;p = 0.02). Mesh exposures were identified as outpatient (20%) or intraoperative (80%). All underwent operative debridement, in which nine were managed with skin reclosure, two with partial closure, and four healed by secondary intention. Five patients required excision of unincorporated mesh. Four patients required further debridement from chronic surgical site occurrences; however, all mesh exposure patents healed after a mean of 260.8 ± 313.2 days and retained original mesh. The recurrence rate was 6.7% for mesh exposure patients.

CONCLUSION

When faced with mesh exposure, resorbable biosynthetic mesh placed in onlay fashion was retained in all patients. Patients with a history of diabetes or COPD have increased risk of mesh exposure and should be counseled.

Concurrent Panniculectomy With Abdominal Wall Reconstruction: A Propensity-scored Matched Study of Quality Improvement Outcomes

Background

Concurrent panniculectomy with abdominal wall reconstruction (CP-AWR) as a single-stage operation has reported increased complications, but constant quality improvement can improve results. This study describes outcomes for 21 years, impacted by evidence-based-practice changes.

Methods

Prospectively maintained database was reviewed for CP-AWR and separated by surgery date: "early" (2002-2016) and "recent" (2017-2023). A 1:1 propensity-scored matching was performed based on age, tobacco use, body mass index (BMI), American Society of Anesthesiologists (ASA) score, wound class, and defect size.

Results

Of 701 CP-AWRs, 196 pairs matched. Match criteria were not significantly different between early and recent groups, except for BMI (34.6 ± 7.2 versus 32.1 ± 6.01 kg/m2; P = 0.001). Groups were comparable in sex and diabetes, but recent patients had fewer recurrent hernias (71.4% versus 56.1%; P = 0.002). Recent patients had more biologic (21.9% versus 49.0%; P < 0.001) and preperitoneal mesh (87.2% versus 97.4%; P = 0.005). Readmission and reoperation did not significantly differ, but length of stay (8.3 ± 6.7 versus 6.5 ± 3.4 d; P = 0.001) and wound complications decreased over time (50.5% versus 25.0%; P < 0.001). Hernia recurrence rates improved (6.6% versus 1.5%; P = 0.019), but follow-up was shorter (50.9 ± 52.8 versus 22.9 ± 22.6 months; P < 0.0001).

Conclusions

Despite patient complexity, outcomes of CP-AWR improved with implementation of evidence-based-practice changes in preoperative optimization, intraoperative technique, and postoperative care. This large dataset demonstrates the safety of a single-stage repair that should be part of hernia surgeons' repertoire.

Combined use of composite mesh and acellular dermal matrix graft for abdominal wall repair following tumour resection

BACKGROUND

Surgeries for sarcomas in the abdominal wall require wide resections, often radical en bloc resections, which generate major defects involving a very complex repair. The combined use of porcine dermal xenografts, together with composite meshes, may assist in the repair of these defects with minimal complications.

METHOD

We present a series of 19 patients (10 males and 9 females), with a mean age of 53.2 years (range: 11-86 years) treated in the Sarcoma Unit of the Virgen de la Arrixaca University Hospital from January 2015 to December 2021. Histopathologically, there were four chondrosarcomas (21%), three Ewing sarcomas (15.7%), two desmoid tumours (10.5%), two undifferentiated pleomorphic sarcomas (10.5%), two well-differentiated liposarcomas (10.5%), two leiomyosarcomas (10.5%), one synovial sarcoma, one dermatofibrosarcoma protuberans, one fibromyxoid sarcoma (or Evans tumour), and one metastasis from an adenocarcinoma of unknown origin. All the patients were resected following surgical oncology principles and reconstructed by means of the combined use of a composite mesh acting as a neoperitoneum and a porcine dermal xenograft acting as an abdominal neofascia.

RESULTS

The mean size of the defects generated after surgery for tumour excision was 262.8 cm2 (range: 150-600 cm2). After a mean follow-up of 38 months, six patients (31.5%) developed complications-two cases of wound dehiscence, one case of surgical wound infection, one case of graft partial necrosis, one case of anastomotic leak and one death due to multiorgan failure secondary to massive bronchoaspiration.

CONCLUSION

Surgeries for sarcomas of the abdominal wall require wide oncological resections, which generate major abdominal wall defects. The repair of these defects by means of the combined use of synthetic and biological meshes is a technique associated with minimal complications and excellent medium-term results.

Quality of life measures and cost analysis of biologic versus synthetic mesh for ventral hernia repair: The Preventing Recurrence in Clean and Contaminated Hernias randomized clinical trial

BACKGROUND

Although the most durable method for ventral hernia repairs involves using mesh, whether to use biologic mesh versus synthetic mesh remains controversial. This study aimed to compare synthetic and biologic meshes with respect to patient-reported quality of life scores and costs after ventral hernia repair surgeries.

METHODS

This study is part of the Preventing Recurrence in Clean and Contaminated Hernias (PRICE) pragmatic randomized control trial conducted from March 2014 through October 2018. Patients were randomized 1:1 to undergo ventral hernia repair using either a biologic or synthetic mesh. The coprimary outcomes were 2-year changes in Visual Analog Scale, Activities Assessment Scale, Hernia-Related Quality-of-Life Survey, and Short-Form 36 Health Survey (SF-36) quality-of-life scores from repair. The secondary outcome was the overall cost per patient.

RESULTS

Among the 165 patients included in the study, 82 were randomized to biologic meshes and 83 to synthetic meshes. There were no significant differences in the performance between the 2 mesh types with regard to quality-of-life measures using a mixed model approach. This result was consistent even when performing subgroup analysis based on wound contamination. However, nonparametric tests comparing the differences in quality-of-life measures from preoperative to 24-month postoperative timepoints revealed that the synthetic mesh group showed a greater reduction in disability than biologic mesh for the SF-36 (median [interquartile range] of 20 [5-30] vs 6 [1-20], P = .025). This difference was due to reductions in the physical role limitations (62 [0-100] vs 0 [0-50], P = .018) and the pain (38 [12-50] vs 12 [0-25], P = .012) domains of the SF-36. Overall cost per patient was greater for biologic meshes (mean [95% confidence interval] of $80,420 [$66,485-$94,355] vs $61,036 [$48,946-$73,125], P = .038), regardless of insurance type.

CONCLUSION

In this randomized clinical trial, there were no differences in changes in quality-of-life scores at the 2-year timepoint except for the SF-36, where the synthetic mesh may be associated with less pain and physical role limitations than the biologic mesh. Overall costs per patient were less for synthetic than biologic mesh.

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.

Outcomes of Complex Abdominal Wall Reconstruction with Biologic Mesh in Patients with 8 Years of Follow-Up

BACKGROUND

While many studies evaluated outcomes of abdominal wall reconstruction with biologic mesh, long-term data is lacking. In this study, we sought to analyze the outcomes of complex AWR with biologic mesh in a robust cohort of patients with a mean follow up of 8 years.

METHODS

We conducted a longitudinal study of AWR patients from 2005 to 2019. Hernia recurrence was the primary outcome, and surgical site occurrence was the secondary outcome. Predictive/protective factors were identified using a Cox proportional hazards regression models.

RESULTS

We identified 109 consecutive patients who met the inclusion criteria. Patient's mean (± SD) age was 57.5 ± 11.8 years, mean body mass index was 30.7 ± 7.2 kg/m2, and mean follow-up time was 96.2 ± 15.9 months. Fifty-six percent had clean defects, 34% had clean-contaminated defects, and 10% had contaminated/infected defects. Patients had a mean defect size of 261 ± 199.6 cm2 and mean mesh size of 391.3 ± 160.2 cm2. Nineteen patients (17.4%) developed HR at the final follow-up date. Obesity was independently associated with a four-fold higher risk of HR (hazard ratio, 3.98; 95%CI, 1.34 to 14.60, p = 0.02). SSOs were identified in 24.8% of patients. A prior hernia repair was associated with a three-fold higher risk of SSOs (Odds ratio, 3.13; 95%CI, 1.10 to 8.94, p = 0.03). No patient developed mesh infection.

CONCLUSION

These longitudinal data demonstrate that complex AWR with biologic mesh provides long-term durable outcomes with acceptable HR and SSO rates despite high contamination levels, patients complexity, and large defect size.

Outcomes of Abdominal Wall Reconstruction with a Bovine versus a Porcine Acellular Dermal Matrix: A Propensity Score-Matched Analysis

BACKGROUND

Abdominal wall reconstruction (AWR) is one of the most commonly performed procedures, yet large comparative studies comparing outcomes of AWR using bovine acellular dermal matrix (BADM) and porcine acellular dermal matrix (PADM) are lacking.

METHODS

In this retrospective cohort study of patients who underwent AWR from March of 2005 to June of 2019, the primary comparative outcome measure was hernia recurrence with BADM versus PADM. The secondary outcome was the incidence of surgical-site occurrence (SSO) and surgical-site infection. A propensity score matching approach was applied to compare the clinical outcomes between the two study groups.

RESULTS

The authors identified 725 patients who underwent AWR using BADM (50.5%) or PADM (49.5%). Their mean ± SD age was 59.8 ± 11.5 years, mean body mass index was 31.4 ± 6.7 kg/m 2 , and mean follow-up time was 42 ± 29 months. With propensity score matching, 219 matched pairs were identified. Hernia recurrence rates in BADM (11.4%) and PADM (13.7%) groups did not differ significantly ( P = 0.793). SSO (26.5% versus 29.2%; P = 0.518) and SSI (13.2% versus 11%; P = 0.456) rates did not differ significantly in the PADM and BADM groups, respectively. Conditional logistic regression model and marginal Cox proportional hazards regression model determined that type of acellular dermal matrix was not significantly associated with SSOs (adjusted OR, 1.11; 95% CI, 0.74 to 1.70; P = 0.589) or hernia recurrence (adjusted hazard ratio, 0.85; 95% CI, 0.50 to 1.42; P = 0.52).

CONCLUSIONS

Both BADMs and PADMs provide durable, long-term outcomes. The hernia recurrence and postoperative surgical complication rates were not significantly different between BADM and PADM.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

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.

The incidence and impact of enterotomy during laparoscopic and robotic ventral hernia repair: a nationwide readmissions analysis

INTRODUCTION

Our aim was to define the national incidence of enterotomy (ENT) during minimally invasive ventral hernia repair (MIS-VHR) and evaluate impact on short-term outcomes.

METHODS

The 2016-2018 Nationwide Readmissions Database was queried using ICD-10 codes for MIS-VHR and enterotomy. All patients had 3-months follow-up. Patients were stratified by elective status; patients without ENT (No-ENT) were compared against ENT patients.

RESULTS

In total, 30,025 patients underwent LVHR and ENT occurred in 388 (1.3%) patients; 19,188 (63.9%) cases were elective including 244 elective-ENT patients. Incidence was similar between elective versus non-elective cohorts (1.27% vs 1.33%; p = 0.674). Compared to laparoscopy, ENT was more common during robotic procedures (1.2% vs 1.7%; p = 0.004). Comparison of elective-No-ENT vs elective-ENT showed that elective-ENT patients had a longer median LOS (2 vs 5 days; p < 0.001), higher mean hospital cost ($51,656 vs $76,466; p < 0.001), increased rates of mortality (0.3% vs 2.9%; p < 0.001), and higher 3-month readmission (10.1% vs 13.9%; p = 0.048). Non-elective cohort comparison demonstrated non-elective-ENT patients had a longer median LOS (4 vs 7 days; p < 0.001), higher mean hospital cost ($58,379 vs $87,850; p < 0.001), increased rates of mortality (0.7% vs 2.1%;p < 0.001), and higher 3-month readmission (13.6% vs 22.2%; p < 0.001). In multivariable analysis (odds ratio, 95% CI), higher odds of enterotomy were associated with robotic-assisted procedures (1.386, 1.095-1.754; p = 0.007) and older age (1.014, 1.004-1.024; p = 0.006). Lower odds of ENT were associated with BMI > 25 kg/m² (0.784, 0.624-0.984; p = 0.036) and metropolitan teaching vs metropolitan non-teaching (0.784, 0.622-0.987; p = 0.044). ENT patients (n = 388) were more likely to be readmitted with post-operative infection (1.9% vs 4.1%; p = 0.002) or bowel obstruction (1.0% vs 5.2%;p < 0.001) and more likely to undergo reoperation for intestinal adhesions (0.3% vs 1.0%; p = 0.036).

CONCLUSION

Inadvertent ENT occurred in 1.3% of MIS-VHRs, had similar rates between elective and urgent cases, but was more common for robotic procedures. ENT patients had a longer LOS, and increased cost and infection, readmission, re-operation and mortality rates.

Open preperitoneal ventral hernia repair: Prospective observational study of quality improvement outcomes over 18 years and 1,842 patients

BACKGROUND

This study aimed to describe progressive evidence-based changes in perioperative management of open preperitoneal ventral hernia repair and subsequent surgical outcomes and to analyze factors that affect recurrence and wound complications.

METHODS

Prospective, tertiary hernia center data (2004-2021) were examined for patients undergoing midline open preperitoneal ventral hernia repair with mesh. "Early" (2004-2012) and "Recent" (2013-2021) groups were based on surgery date.

RESULTS

Comparison of Early (n = 675) versus Recent (n = 1,167) groups showed that Recent patients were, on average, older (56.9 ± 12.6 vs 58.7 ± 12.1 years; P < .001) with a lower body mass index (33.5 ± 8.3 vs 32.0 ± 6.8 kg/m²; P = .003) and a higher number of comorbidities (3.6 ± 2.2 vs 5.2 ± 2.6; P < .001). Recent patients had higher proportions of prior failed ventral hernia repair (46.5% vs 60.8%; P < .001), larger hernia defects (199.7 ± 232.8 vs 214.4 ± 170.5 cm²; P < .001), more Center for Disease Control class 3 or 4 wounds (11.3% vs 18.6%; P < .001), and more component separations (22.5% vs 45.7%; P < .001). Hernia recurrence decreased over time (7.1% vs 2.4%; P < .001), as did wound complication rates (26.7% vs 13.2%; P < .001). Comparing respective multivariable analyses (Early versus Recent), wound complications were associated with panniculectomy (odds ratio [95% confidence interval]: 2.9 [1.9-4.5], P < .001 vs 2.1 [1.4-3.3], P < .01), contaminated wounds (2.1 [1.1-3.7], P = .02 vs 1.8 [1.1-3.1], P = .02), anterior component separation technique (1.8 [1.1-2.9], P = .02 vs 3.2[1.9-5.3], P < .01), and operative time (per minute: 1.01 [1.008-1.015], P < .01 vs 1.004 [1.001-1.007], P < .01). Diabetes (2.6 [1.7-4.0], P < .01) and tobacco (1.8 [1.1-2.9], P = .02) were only significant in the early group. In both groups, recurrence was associated with wound complication (8.9 [4.1-20.1], P < .01 vs 3.4 [1.3-8.2]. P < .01) and recurrent hernias (4.9 [2.3-11.5], P < .01 vs 2.1 [1.1-4.2], P = .036).

CONCLUSION

Despite significant increased patient complexity over time, detecting and implementing best practices as determined by recurring data analysis of a center's outcomes has significantly improved patient care results.

Observational study of complex abdominal wall reconstruction using porcine dermal matrix: How have outcomes changed over 14 years?

BACKGROUND

Our center has adopted many evidence-based practices to improve outcomes for complex abdominal wall reconstruction with porcine dermal matrix. This study analyzed outcomes over time using porcine dermal matrix in complex abdominal wall reconstruction.

METHODS

Prospective, tertiary hernia center data was examined for patients undergoing complex abdominal wall reconstruction with porcine dermal matrix. Early (2008-2014) and Recent (2015-2021) cohorts were defined by dividing the study interval in half. Multivariable analyses of wound complications and recurrence were performed.

RESULTS

Comparing 117 Early vs 245 Recent patients, both groups had high rates of previously repaired hernias (76.1% vs 67.4%; P = .110), Centers for Disease Control and Prevention class 3 or 4 wounds (76.0% vs 66.6%; P = .002), and very large hernia defects (320 ± 317 vs 282 ± 164 cm²; P = .640). Recent patients had higher rates of preoperative botulinum injection (0% vs 21.2%; P < .001), posterior component separation (15.4% vs 35.5%; P < .001), and delayed primary closure (23.1% vs 38.8%; P < .001), but lower rates of concurrent panniculectomy (32.3% vs 27.8%; P = .027) and similar anterior component separation (29.1% vs 18.2%; P = .060). Most mesh was placed preperitoneal (74.4% vs 93.3%; P < .001). Recent patients had less inlay (9.4% vs 2.1%; P < .01) and other mesh locations as fascial closure rate increased (88.0% vs 95.5%; P < .001). Over time, there was a decrease in wound complications (42.1% vs 14.3%; P < .001), length of stay (median [interquartile range]:8 [6-13] vs 7 [6-9]; P = .003), and 30-day readmissions (32.7% vs 10.3%; P < .001). Hernia recurrence decreased (10.3% vs 3.7%; P = .016) with mean follow-up of 2.8 ± 3.2 and 1.7 ± 1.7 years, respectively. Respective multivariable models(odds ratio, 95% confidence interval) demonstrated an increased risk of wound complications with diabetes (2.65, 1.16-5.98; P = .020), panniculectomy (2.63, 1.21-5.73; P = .014), and anterior component separation (5.1, 1.98-12.9; P < .001), with recurrence risk increased by wound complication (3.8, 1.4-2-7.62; P = .032).

CONCLUSION

Porcine dermal matrix in complex abdominal wall reconstruction performs well with low recurrence rates. Internal assessment and implementation of evidence-based practices improved outcomes such as length of stay, wound complications, and recurrence rate.

Predicting rare outcomes in abdominal wall reconstruction using image-based deep learning models

BACKGROUND

Deep learning models with imbalanced data sets are a challenge in the fields of artificial intelligence and surgery. The aim of this study was to develop and compare deep learning models that predict rare but devastating postoperative complications after abdominal wall reconstruction.

METHODS

A prospectively maintained institutional database was used to identify abdominal wall reconstruction patients with preoperative computed tomography scans. Conventional deep learning models were developed using an 8-layer convolutional neural network and a 2-class training system (ie, learns negative and positive outcomes). Conventional deep learning models were compared to deep learning models that were developed using a generative adversarial network anomaly framework, which uses image augmentation and anomaly detection. The primary outcomes were receiver operating characteristic values for predicting mesh infection and pulmonary failure.

RESULTS

Computed tomography scans from 510 patients were used with a total of 10,004 images. Mesh infection and pulmonary failure occurred in 3.7% and 5.6% of patients, respectively. The conventional deep learning models were less effective than generative adversarial network anomaly for predicting mesh infection (receiver operating characteristic 0.61 vs 0.73, P < .01) and pulmonary failure (receiver operating characteristic 0.59 vs 0.70, P < .01). Although the conventional deep learning models had higher accuracies/specificities for predicting mesh infection (0.93 vs 0.78, P < .01/.96 vs .78, P < .01) and pulmonary failure (0.88 vs 0.68, P < .01/.92 vs .67, P < .01), they were substantially compromised by decreased model sensitivity (0.25 vs 0.68, P < .01/.27 vs .73, P < .01).

CONCLUSION

Compared to conventional deep learning models, generative adversarial network anomaly deep learning models showed improved performance on imbalanced data sets, predominantly by increasing model sensitivity. Understanding patients who are at risk for rare but devastating postoperative complications can improve risk stratification, resource utilization, and the consent process.

Component Separation: A Case Report of Hybrid and Synthetic Absorbable Mesh Use for Complex Large Ventral Hernia Reparation

Ventral abdominal hernias are a common abdominal wall defect in the United States. We present a 50-year-old Caucasian male with a large (>18 cm) abdominal wall defect. An extensive complex abdominal wall reconstruction with advanced bilateral fascial flaps/component separation and repair of the abdominal wall defect was planned to restore the appropriate abdominal wall anatomic contour. The use of double mesh in large abdominal wall defects is still a relatively new documented technique. Only two case series detail the same technique used on this patient, with no articles on using a hybrid mesh with a synthetic absorbable mesh. This case uses an underlay and onlay mesh technique, with a hybrid mesh, Tela Biologics (Malvern, PA, USA), under the muscle, in this case, intraperitoneal bridging the gap. The anterior rectus sheath was reinforced with intercepted 0-Ethibond sutures (Ethicon/J&J, Bridgewater, NJ, USA) and then reinforced with a synthetic absorbable mesh (Phasix^TM, Becton Dickinson, Franklin Lakes, NJ). The outcome with this patient shows more research should be conducted on considering long-term results with the types of mesh and the question of whether there are additional benefits when using two different types of mesh and their placement in the sandwich technique.

State-of-the-art abdominal wall reconstruction and closure

Open ventral hernia repair is one of the most common operations performed by general surgeons. Appropriate patient selection and preoperative optimization are important to ensure high-quality outcomes and prevent hernia recurrence. Preoperative adjuncts such as the injection of botulinum toxin and progressive preoperative pneumoperitoneum are proven to help achieve fascial closure in patients with hernia defects and/or loss of domain. Operatively, component separation techniques are performed on complex hernias in order to medialize the rectus fascia and achieve a tension-free closure. Other important principles of hernia repair include complete reduction of the hernia sac, wide mesh overlap, and techniques to control seroma and other wound complications. In the setting of contamination, a delayed primary closure of the skin and subcutaneous tissues should be considered to minimize the chance of postoperative wound complications. Ultimately, the aim for hernia surgeons is to mitigate complications and provide a durable repair while improving patient quality of life.

Transcriptomic Regulation of Macrophages by Matrix-Bound Nanovesicle-Associated Interleukin-33

The innate immune response, particularly the phenotype of responding macrophages, has significant clinical implications in the remodeling outcome following implantation of biomaterials and engineered tissues. In general, facilitation of an anti-inflammatory (M2-like) phenotype is associated with tissue repair and favorable outcomes, whereas pro-inflammatory (M1-like) activation can contribute to chronic inflammation and a classic foreign body response. Biologic scaffolds composed of extracellular matrix (ECM) and, more recently, matrix-bound nanovesicles (MBV) embedded within the ECM are known to direct macrophages toward an anti-inflammatory phenotype and stimulate a constructive remodeling outcome. The mechanisms of MBV-mediated macrophage activation are not fully understood, but interleukin-33 (IL-33) within the MBV appears critical for M2-like activation. Previous work has shown that IL-33 is encapsulated within the lumen of MBV and stimulates phenotypical changes in macrophages independent of its canonical surface receptor stimulation-2 (ST2). In the present study, we used next-generation RNA sequencing to determine the gene signature of macrophages following exposure to MBV with and without intraluminal IL-33. MBV-associated IL-33 instructed an anti-inflammatory phenotype in both wild-type and st2-/- macrophages by upregulating M2-like and downregulating M1-like genes. The repertoire of genes regulated by ST2-independent IL-33 signaling were broadly related to the inflammatory response and crosstalk between cells of both the innate and adaptive immune systems. These results signify the importance of the MBV intraluminal protein IL-33 in stimulating a pro-remodeling M2-like phenotype in macrophages and provides guidance for the designing of next-generation biomaterials and tissue engineering strategies. Impact statement The phenotype of responding macrophages is predictive of the downstream remodeling response to an implanted biomaterial. The clinical impact of macrophage phenotype has motivated studies to investigate the factors that regulate macrophage activation. Matrix-bound nanovesicles (MBV) embedded within the extracellular matrix direct macrophages toward an anti-inflammatory (M2)-like phenotype that is indicative of a favorable remodeling response. Although the mechanisms of MBV-mediated macrophage activation are not fully understood, the intraluminal protein interleukin-33 (IL-33) is clearly a contributing signaling molecule. The present study identifies those genes regulated by MBV-associated IL-33 that promote a pro-remodeling M2-like macrophage activation state and can guide future therapies in regenerative medicine.

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.

Xenogeneic Mesh Provides Safe and Durable Long-Term Outcomes in Abdominal Wall Reconstruction of High-Risk Centers for Disease Control and Prevention Class III and IV Defects

OBJECTIVE

Evaluate long-term outcomes of abdominal wall reconstruction (AWR) using xenogeneic mesh in patients with Centers for Disease Control and Prevention (CDC) class III/IV defects. We hypothesized that AWR with xenogeneic mesh results in acceptable outcomes.

BACKGROUND

Optimal mesh selection in AWR of CDC class III/IV defects is controversial. Outcomes using xenogeneic mesh are lacking.

METHODS

We conducted a retrospective cohort study of patients who underwent AWR using xenogeneic mesh in CDC class III/IV defects from March 2005 to June 2019. Primary outcome was hernia recurrence (HR). Secondary outcomes were surgical site occurrence (SSO) and surgical site infection (SSI).

RESULTS

Of consecutive 725 AWRs, we identified 101 patients who met study criteria. Sixty-eight patients had class III defects, while 33 had class IV defects. Patients had a mean age of 61.3 ± 11.1 years, mean body mass index of 31.8 ± 7.3 kg/m2, and mean follow-up time of 41.9 ± 26.3 months. Patients had HR rate of 21%, SSO rate of 49%, and SSI rate of 24. Class IV defects were predictive of SSOs (odds ratio [OR], 2.88; 95% confidence interval [CI], 1.11-7.42; P = 0.029) but not HR (hazard ratio, 1.60; 95% CI, 0.59-4.34; P = 0.355) or SSIs (OR, 2.62; 95% CI, 0.85-8.10; P = 0.094).

CONCLUSIONS

Patients with class IV defects have a higher risk of SSOs, but not HR or SSIs, compared with patients with class III defects. Despite the high level of defect contamination, AWR with xenogeneic mesh demonstrated acceptable HR, SSO, and SSI rates. Therefore, safe and durable long-term outcomes are achievable in single-stage AWR using xenogeneic mesh for CDC class III/IV defects.

Comparative Effectiveness Analysis of Resorbable Synthetic Onlay and Biologic Intraperitoneal Mesh for Abdominal Wall Reconstruction: A 2-Year Match-Paired Analysis

BACKGROUND

Abdominal wall reconstruction persists as a challenging surgical issue with a multitude of management strategies available. The aim of this study was to examine the efficacy of resorbable synthetic mesh onlay plane against biologic mesh in the intraperitoneal plane.

METHODS

A single-center, two-surgeon, 5-year retrospective review (2014 to 2019) was performed examining subjects who underwent abdominal wall reconstruction in the onlay plane with resorbable synthetic mesh or in the intraperitoneal plane with biologic mesh. A matched paired analysis was conducted. Data examining demographic characteristics, intraoperative variables, postoperative outcomes, and costs were analyzed.

RESULTS

Eighty-eight subjects (44 per group) were identified (median follow-up, 24.5 months). The mean age was 57.7 years, with a mean body mass index of 30.4 kg/m2. The average defect size was 292 ± 237 cm2, with most wounds being clean-contaminated (48.9 percent) and 55 percent having failed prior repair. Resorbable synthetic mesh onlay subjects were significantly less likely (4.5 percent) to experience recurrence compared to biologic intraperitoneal mesh subjects (22.7 percent; p < 0.026). In addition, mesh onlay suffered fewer postoperative surgical-site occurrences (18.2 percent versus 40.9 percent; p < 0.019) and required fewer procedural interventions (11.4 percent versus 36.4 percent; p < 0.011), and was also associated with significantly lower total costs ($16,658 ± $14,930) compared to biologic intraperitoneal mesh ($27,645 ± $16,864; p < 0.001).

CONCLUSIONS

Abdominal wall reconstruction remains an evolving field, with various techniques available for treatment. When faced with hernia repair, resorbable synthetic mesh in the onlay plane may be preferable to biologic mesh placed in the intraperitoneal plane because of lower long-term recurrence rates, surgical-site complications, and costs.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

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.

Biologic vs Synthetic Mesh for Single-stage Repair of Contaminated Ventral Hernias: A Randomized Clinical Trial

IMPORTANCE

Biologic mesh is widely used for reinforcing contaminated ventral hernia repairs; however, it is expensive and has been associated with high rates of long-term hernia recurrence. Synthetic mesh is a lower-cost alternative but its efficacy has not been rigorously studied in individuals with contaminated hernias.

OBJECTIVE

To determine whether synthetic mesh results in superior reduction in risk of hernia recurrence compared with biologic mesh during the single-stage repair of clean-contaminated and contaminated ventral hernias.

DESIGN, SETTING, AND PARTICIPANTS

This multicenter, single-blinded randomized clinical trial was conducted from December 2012 to April 2019 with a follow-up duration of 2 years. The trial was completed at 5 academic medical centers in the US with specialized units for abdominal wall reconstruction. A total of 253 adult patients with clean-contaminated or contaminated ventral hernias were enrolled in this trial. Follow-up was completed in April 2021.

INTERVENTIONS

Retromuscular synthetic or biologic mesh at the time of fascial closure.

MAIN OUTCOMES AND MEASURES

The primary outcome was the superiority of synthetic mesh vs biologic mesh at reducing risk of hernia recurrence at 2 years based on intent-to-treat analysis. Secondary outcomes included mesh safety, defined as the rate of surgical site occurrence requiring a procedural intervention, and 30-day hospital direct costs and prosthetic costs.

RESULTS

A total of 253 patients (median [IQR] age, 64 [55-70] years; 117 [46%] male) were randomized (126 to synthetic mesh and 127 to biologic mesh) and the follow-up rate was 92% at 2 years. Compared with biologic mesh, synthetic mesh significantly reduced the risk of hernia recurrence (hazard ratio, 0.31; 95% CI, 0.23-0.42; P < .001). The overall intent-to-treat hernia recurrence risk at 2 years was 13% (33 of 253 patients). Recurrence risk with biologic mesh was 20.5% (26 of 127 patients) and with synthetic mesh was 5.6% (7 of 126 patients), with an absolute risk reduction of 14.9% with the use of synthetic mesh (95% CI, -23.8% to -6.1%; P = .001). There was no significant difference in overall 2-year risk of surgical site occurrence requiring a procedural intervention between the groups (odds ratio, 1.22; 95% CI, 0.60-2.44; P = .58). Median (IQR) 30-day hospital direct costs were significantly greater in the biologic group vs the synthetic group ($44 936 [$35 877-$52 656] vs $17 289 [$14 643-$22 901], respectively; P < .001). There was also a significant difference in the price of the prosthetic device between the 2 groups (median [IQR] cost biologic, $21 539 [$20 285-$23 332] vs synthetic, $105 [$105-$118]; P < .001).

CONCLUSIONS AND RELEVANCE

Synthetic mesh demonstrated superior 2-year hernia recurrence risk compared with biologic mesh in patients undergoing single-stage repair of contaminated ventral hernias, and both meshes demonstrated similar safety profiles. The price of biologic mesh was over 200 times that of synthetic mesh for these outcomes.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02451176.

Platelet-rich plasma enhances mechanical strength of strattice in rat model of ventral hernia repair

Incisional hernia is a common complication of hernia repair despite the development of various synthetic and bio-synthetic repair materials. Poor long-term mechanical strength, leading to high recurrence rates, has limited the use of acellular dermal matrices (ADMs) in ventral hernia repair (VHR). Biologically derived meshes have been an area of increasing interest. Still these materials bring the risk of more aggressive immune response and fibrosis in addition to the mechanical failures suffered by the synthetic materials. Platelet-rich plasma (PRP), a growth-factor-rich autologous blood product, has been shown to improve early neovascularization, tissue deposition, and to decrease the rates of recurrence. Here, we demonstrate that PRP promotes the release of growth factors stromal derived factor (SDF)-1, transforming growth factor-beta, and platelet-derived growth factor in a dose-dependent manner. Additionally, we utilize an aortic ring angiogenesis assay to show that PRP promotes angiogenesis in vitro. A rat model of VHR using StratticeTM ADM demonstrates similar findings in vivo, corresponding with the increased expression of vascular endothelial growth factor and collagen type 1 alpha 1. Finally, we show that the molecular and cellular activity initiated by PRP results in an increased mechanical stiffness of the hernia repair mesh over time. Collectively, these data represent an essential step in demonstrating the utility and the mechanism of platelet-derived plasma in biomaterial-aided wound healing and provide promising preclinical data that suggest such materials may improve surgical outcomes.

Cost-effectiveness analysis of resorbable biosynthetic mesh in contaminated ventral hernia repair

BACKGROUND

The aim of this study was to compare, in terms of cost and serious complications, the use of biosynthetic resorbable parietal mesh with biologic mesh in patients undergoing contaminated ventral hernia repair (modified Ventral Hernia Working Group grade 3). Poly-4-hydroxy-butyrate (P4HB) biosynthetic mesh has rarely been the subject of comparative studies in the context of contamination. Data are required to confirm the effects of a transition from biological mesh to biosynthetic resorbable mesh.

PATIENTS AND METHODS

A cost-effectiveness analysis was conducted. It was based on a decision analysis model built with clinical and economic data issued from a before-after study that included 94 patients hospitalized for ventral hernia repair at the University Hospital of Strasbourg (France) from June 2011 to February 2018. The effectiveness endpoint was the number of patients presenting with a serious specific complication or a general complication at 6 months. Data for surgical hospitalization stays, home hospitalizations and ambulatory care costs were included.

RESULTS

We found fewer serious complications with biosynthetic mesh: 21% versus 33% with biologic mesh. A cost savings of US $5146 was determined. Deterministic sensitivity analyses and a probabilistic analysis confirmed our findings and the robustness of the model.

CONCLUSION

P4HB biosynthetic resorbable mesh appeared to be the most effective and the least costly option. Additional data will be needed to confirm the superiority of biosynthetic mesh in terms of the recurrence risk reduction over a longer period.

Outcomes of mid-term and long-term degradable biosynthetic meshes in single-stage open complex abdominal wall reconstruction

OBJECTIVE

To assess clinical outcomes in patients that underwent open single-stage complex abdominal wall reconstruction (CAWR) with biosynthetic mesh.

METHODS

Retrospective observational study of two prospectively registered series of consecutive patients undergoing CAWR with either long-term degradable (LTD) Phasix^™ or mid-term degradable (MTD) BIO-A^® biosynthetic mesh in a single institution between June 2016 and December 2019.

RESULTS

From 169 patients with CAWR, 70 consecutive patients were identified who underwent CAWR with either LTD or MTD biosynthetic mesh. More than 85% of patients had an incisional hernia that could be classified as moderately complex to major complex due to a previous wound infection (67%), one or more complicating comorbidities (87.1%), one or more complicating hernia characteristics (75.7%) or contaminated or dirty defects (37.1%). Concomitant component separation was performed in 43 of 70 patients (61.4%). Overall surgical site infection (SSI) rate in these CAWR patients was 45.7%. Seventeen of 70 patients (24.3%) had computed tomography (CT) - and culture-confirmed SSI in direct contact of mesh, suspicious of mesh infection. Mesh removal for persistent local infection occurred in 10% (7 of 70) after a median of 229 days since surgery. Salvage rate of mesh after direct contact with infection was 58.8%. All removed meshes were in the LTD group. Seven patients (10%) had a recurrence; four patients in the LTD group (10%) had a recurrence at a median follow-up of 35 months and three patients in the MTD group (10%) at a median follow-up of 11 months. Three of the seven recurrences occurred in patients with SSI in persistent and direct contact with mesh.

CONCLUSIONS

Comorbid patients undergoing open complex abdominal wall reconstruction are at high risk of postoperative wound complications regardless of which type of biosynthetic mesh is used. When in persistent and direct contact with infection, long-term biodegradable biosynthetic meshes may need to be removed, whereas mid-term biodegradable biosynthetic meshes can be salvaged.

Biologic mesh implantation is associated with serious abdominal wall complications in patients undergoing emergency abdominal surgery: A randomized-controlled clinical trial

BACKGROUND

Open, emergency abdominal surgery is associated with a high incidence of fascial dehiscence and incisional hernia. Implantation of biologic meshes potentially reinforces the abdominal wall and therefore decreases such complications. The aim of this prospective randomized study was to compare the outcome after prophylactic intraperitoneal implantation of a biologic Strattice mesh (Allergan, Dublin, Ireland) with standard abdominal closure in patients undergoing emergency abdominal surgery.

METHODS

A two-arm randomized clinical trial was performed in patients undergoing emergency abdominal surgery at Bern University Hospital, University of Bern, Switzerland, from April 2016 to March 2019. Patients were randomly assigned to prophylactic implantation of a biological intraperitoneal mesh using Strattice, Allergan (mesh group), or standard abdominal closure using a single, continuous running suture (no-mesh group). Because of safety concerns, patient enrollment was closed prematurely.

RESULTS

Eligibility for inclusion was assessed in 61 patients. A total of 48 patients were randomized (21 in the mesh group, 28 in the no-mesh group). No differences in baseline characteristics were found. Abdominal wall complications requiring reoperations were more frequent in the mesh group compared to the no-mesh group (5 [83.3%] of 13 vs. 1 [14.3%] of 13 patients, p = 0.026). Mesh-associated abdominal wall complications included nonintegration of the mesh into the abdominal wall, dissolution of the mesh, and mesh-related infections.

CONCLUSION

In patients undergoing emergency abdominal surgery, intraperitoneal biologic Strattice mesh implantation is associated with significantly more frequent abdominal wall complications requiring reoperation. Therefore, the use of such meshes cannot be recommended in the contaminated environment of emergency abdominal surgery.

LEVEL OF EVIDENCE

Therapeutic, level I.

Slowly absorbable mesh in contaminated incisional hernia repair: results of a French multicenter study

PURPOSE

To analyze the postoperative morbidity and 1-year recurrence rate of incisional hernia repair using a biosynthetic long-term absorbable mesh in patients at higher risk of surgical infection in a contaminated surgical field.

METHODS

All patients undergoing incisional hernia repair in a contaminated surgical field with the use of a biosynthetic long-term absorbable mesh (Phasix®) between May 2016 and September 2018 at six participating university centers were included in this retrospective cohort and were followed-up until September 2019. Regarding the risk of surgical infection, patients were classified according to the modified Ventral Hernia Working Group classification. Preoperative, operative and postoperative data were collected. All patients' surgical site infections (SSIs) and occurrences (SSOs) and recurrence rates were the endpoints of the study.

RESULTS

Two hundred and fifteen patients were included: 170 with mVHWG grade 3 (79%) and 45 with mVHWG grade 2 (21%). The SSI and SSO rates at 12 months were 22.3% and 39.5%, respectively. According to the Dindo-Clavien classification, 43 patients (20.0%) had at least one minor complication, and 57 patients (26.5%) had at least one major complication. Among the 121 patients (56.3%) having at least 1 year of follow-up, the clinical recurrence rate was 12.4%. Multivariate analysis showed that a concomitant gastrointestinal procedure was an independent risk factor for surgical infection (OR = 2.61), and an emergency setting was an independent risk factor for major complications (OR = 11.9).

CONCLUSION

The use of a biosynthetic absorbable mesh (Phasix®) is safe in a contaminated surgical field, with satisfying immediate postoperative and 1-year results.

TRIAL REGISTRATION

The study is registered on Clinical Trial ID: NCT04132986.

What results can be expected one year after complex incisional hernia repair with biosynthetic mesh?

BACKGROUND

Incisional hernia is a frequent complication after midline laparotomy. The current standard repair includes the use of a synthetic mesh to prevent recurrence. However, the use of a synthetic mesh in a contaminated field carries a higher risk of mesh infection. In this setting biologic and biosynthetic meshes can be used as they resist to infection, but these are absorbable meshes. This raises the question of the risk of recurrence as the mesh disappears. Phasix® is a biosynthetic mesh getting absorbed in 12-18 months. The aim of this study was to assess the 1-year recurrence rate after abdominal-wall repair with a Phasix® mesh.

METHODS

All patients undergoing ventral hernia repair between 2016 and 2018 at the University Hospital of Dijon using a Phasix® mesh were prospectively included in a database. They were all followed-up with a physical exam and a routine CT scan at one year. All postoperative complications were recorded.

RESULTS

Twenty-nine patients were included in the study (55.2% women), with a mean BMI of 30,25 kg/m². Nineteen meshes were sublay and 10 intraperitoneal. Complications at 1 month were mainly mild: Clavien-Dindo I and II (61.1%). No mesh was explanted. There was no chronic infection. The mean length of stay was 11.5 days. The 1-year recurrence rate was 10.3%.

CONCLUSION

Patients having undergone complex ventral hernia repair with a Phasix® mesh have a 1-year recurrence rate of 10.3%. No severe surgical site occurrence was detected. A longer follow-up in a larger number of patients could confirm the place of this mesh in abdominal-wall repair.

Biologic Mesh in Surgery: A Comprehensive Review and Meta-Analysis of Selected Outcomes in 51 Studies and 6079 Patients

BACKGROUND

In recent decades, biologic mesh (BM) has become an important adjunct to surgical practice. Recent evidence-based clinical applications of BM include but are not limited to: reconstruction of abdominal wall defects; breast reconstruction; face, head and neck surgery; periodontal surgery; other hernia repairs (diaphragmatic, hiatal/paraesophageal, inguinal and perineal); hand surgery; and shoulder arthroplasty. Prior systematic reviews of BM in complex abdominal wall hernia repair had several shortcomings that our comprehensive review seeks to address, including exclusion of laparoscopic repair, assessment of risk of bias, use of an acceptable meta-analytic method and review of risk factors identified in multivariable regression analyses.

MATERIALS AND METHODS

We sought articles of BM for open ventral hernia repair reporting on early complications, late complications or recurrences and included minimum of 50. We used the quality in prognostic studies risk of bias assessment tool. Random effects meta-analysis was applied.

RESULTS

This comprehensive review selected 62 articles from 51 studies that included 6,079 patients. Meta-analytic pooling found that early complications are present in about 50%, surgical site occurrences (SSOs) in 37%, surgical site infections (SSIs) in 18%, reoperation in 7%, readmission in 20% and mortality in 3%. Meta-analytic estimates of late outcomes included overall complications (42%), SSOs (40%) and SSIs (22%). Specific SSOs included seroma (14%), hematoma (4%), abscess (10%), necrosis (5%), dehiscence (8%) and fistula formation (5%). Reoperation occurred in about 17%, mesh explantation in 9% and recurrence in 36%.

CONCLUSION

Estimates of nearly all outcomes from individual studies were highly heterogeneous and sensitivity analyses and meta-regressions generally failed to explain this heterogeneity. Recurrence is the only outcome for which there are consistent findings for risk factors. Bridge placement of BM is associated with higher risk of recurrence. Prior hernia repair, history of reintervention and history of mesh removal were also risk factors for increased recurrence.

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.

Surgical Site Infection: The Scourge of Abdominal Wall Reconstruction

Background: Surgical site infection (SSI) is a well-recognized and potentially catastrophic complication of abdominal wall reconstruction (AWR). The authors present a review of the literature surrounding SSI in AWR, exploring prevention and treatment strategies as well as risk factors. Methods: A comprehensive review of the current literature was undertaken. Evidence was reviewed and summarized with particular focus on prevention and treatment strategies available to hernia surgeons. Results: Patient risk factors for SSI are well described in the literature and include obesity, smoking, and other comorbidities. Contaminated hernias and cases involving enterocutaneous fistulae are also at higher risk of SSI. Surgical decisions such as type of mesh, plane of mesh placement, and fascial release may all contribute to SSI risk. To treat established mesh infection, conservative management with antibiotic agents and negative pressure therapy is a reasonable option in some cases. Removal of prosthesis appears to provide favorable results, however, repeat surgery can be problematic Conclusions: Surgical site infection remains an important pathology in the world of AWR. Surgeons have a wealth of tools in their arsenal to prevent and treat SSI and should be aware of the emerging evidence in the fast-moving specialty of hernia surgery. Complex cases should be handled by surgeons and centers with expertise in treating such patients.

Non-cross-linked biological mesh in complex abdominal wall hernia: a cohort study

Purpose

Complex abdominal wall hernia repair (CAWHR) is a challenging procedure. Mesh prosthesis is indicated, but the use of synthetic mesh in a contaminated area may add to overall morbidity. Biological meshes may provide a solution, but little is known about long-term results. The aim of our study was to evaluate clinical efficacy and patient satisfaction following Strattice™ (PADM) placement.

Methods

In this cohort study, all patients operated for CAWHR with PADM in three large community hospitals in Germany were included. Patients underwent abdominal examination, an ultrasound was performed, and patients completed quality-of-life questionnaires. The study was registered in ClinicalTrials.gov under Identifier NCT02168231.

Results

Twenty-seven patients were assessed (14 male, age 67.5 years, follow-up 42.4 months). The most frequent postoperative complication was wound infection (39.1%). In no case, the PADM had to be removed. Four patients had passed away. During outpatient clinic visit, six out of 23 patients (26.1%) had a recurrence of hernia, one patient had undergone reoperation. Five patients (21.7%) had bulging of the abdominal wall. Quality-of-life questionnaires revealed that patients judged their scar with a median 3.5 out of 10 points (0 = best) and judged their restrictions during daily activities with a median of 0 out of 10.0 (0 = no restriction).

Conclusions

Despite a high rate of wound infection, no biological mesh had to be removed. In some cases, therefore, the biological meshes provided a safe way out of desperate clinical situations. Both the recurrence rate and the amount of bulging are high (failure rate 47.8%). The reported quality of life is good after repair of these complex hernias.

Immediate Closure of Abdominal Cavity with Biologic Mesh versus Temporary Abdominal Closure of Open Abdomen in Non-Trauma Emergency Patients (CLOSE-UP Study)

Background: In more than 10% of emergency laparotomies in non-trauma patients, primary fascial closure is not achievable because of excessive visceral edema, which leaves the patient with an open abdomen (OA). An OA harbors an inherent high risk of serious complications, and temporary closure devices are used to achieve delayed fascial closure. A potential new strategy in preventing OA is immediate closure during the emergency procedure with a non-crosslinked biologic mesh. Methods: This is a prospective comparative cohort feasibility study in 13 teaching hospitals in the Netherlands. Non-trauma patients who underwent emergency laparotomy in which regular sutured primary fascial closure was not achievable because of excessive intra-abdominal edema were eligible. In one cohort, Biomesh (n = 20), the abdominal cavity was immediately closed at the emergency laparotomy with a non-crosslinked biologic mesh. In a parallel cohort, Control (n = 20), the resulting OA was managed by temporary abdominal closure (TAC; inlay polyglactin [Vicryl™] mesh [n = 7]) or commercial (ABThera^TM) abdominal negative pressure therapy device (n = 13)). The primary end point was the proportion of closed abdominal cavities at 90 days. Results: At 90 days, 65% (13/20) of the abdominal cavities were closed in the Biomesh cohort versus 45% (9/20) in Controls (p = 0.204). In the Biomesh cohort, seven of 20 (35%) patients had at least one major complication versus 15 of 20 (75%) patients in the Control cohort (p = 0.011). Both the median number of intensive care unit (ICU) and mechanical ventilation days were significantly lower in the Biomesh cohort; one versus 10 (p = 0.002) and 0 versus four (p = 0.003) days, respectively. The number of abdominal reoperations was significantly lower in the Biomesh cohort (median 0 vs. two, p < 0.001; total number five vs. 44). Conclusions: If primary fascial closure cannot be achieved at the emergency laparotomy in non-trauma patients, immediate abdominal closure by use of a non-crosslinked biologic mesh prevents OA management. This results in a non-significant higher proportion of closed abdominal cavities at 90 days compared with OA management with TAC techniques, and in a significant reduction of major complications and reoperations, and a shorter ICU stay.

Absorbable Polyglactin vs. Non-Cross-linked Porcine Biological Mesh for the Surgical Treatment of Infected Incisional Hernia

BACKGROUND

The use of absorbable meshes during contaminated or infected incisional hernia (IH) repair is associated with high morbidity and recurrence rates. Biological meshes might be more appropriate but have been described in highly heterogeneous series. This study aimed at comparing the efficacy of absorbable vs. biological meshes for the treatment of contaminated or infected IH in a homogeneous series with a standardized technique.

METHODS

Data of all patients operated on between 2008 and 2015 for contaminated or infected IH, using an absorbable (A) Vicryl® or a biological (B) Strattice® mesh, were reviewed. Patient characteristics, infectious complication rates, and recurrence-free outcome (RFO) were compared between the two groups. A propensity score methodology was applied to a Cox regression model to deal with unbalanced characteristics between groups.

RESULTS

Patient demographics in A (n = 57) and in B (n = 24) were similar except that B patients had larger parietal defects (p < 0.001) and higher Center for Disease Control (CDC) wound class (p = 0.034). Patients in A had statistically significantly more postoperative early (61.4% vs. 33.3%, p = 0.03) and late (31.2% vs. 8.3%, p = 0.046) infectious complications. Six-, 12-, and 36-month RFO rates were 77%, 47%, and 24%, and 96%, 87%, and 82% in A and B, respectively, p < 0.001. Raw multivariable Cox regression analysis found that B (HR = 0.1, 95% CI [0.03-0.34], p < 0.001) was independently associated with prolonged RFO (HR = 0.091, 95% CI [0.045-0.180], p < 0.001).

CONCLUSION

Biological meshes seem to be superior to absorbable meshes in patients with contaminated or infected incisional hernia. These results need to be confirmed by prospective randomized trials.

The Tensile Strength of Full-Thickness Skin: A Laboratory Study Prior to Its Use as Reinforcement in Parastomal Hernia Repair

Purpose: Parastomal hernia is a common complication of an enterostoma. Current methods of repair have high recurrence rates and are associated with severe complications. Autologous full-thickness skin as reinforcement may reduce the recurrence and complication rates. This study aims to investigates the tensile strength of full-thickness skin; information that is essential if we are to proceed with clinical trials on humans.

Methods: Full-thickness skin samples from 12 donors were tested for tensile strength, as well as the load tolerated by a suture through the skin. Strips of skin were cut out and stretched until breaking point. Sutures were made through skin samples and traction applied until either the tissue or the suture gave way. All done while recording the forces applied using a dynamometer. Identical tests were carried out on commercially available synthetic and biologic graft material for comparison.

Results: The full-thickness skin strips had a median tensile strength of 604 N/cm. This tensile strength was significantly higher than that of the compared materials evaluated in this study. In full-thickness skin, the suture, or tissue endured a median force of 67 N before giving way, which was as high as, or higher than similar sutures through the compared materials.

Conclusions: The tensile strength of full-thickness skin vastly exceeds the physiological forces affecting the abdominal wall, and sutures through skin endure high loads before giving way. The tensile strength of a full-thickness skin graft and the strength of sutures through this material will not limit its use for reinforcement in parastomal hernia repair.

Mesh fistula after ventral hernia repair: What is the optimal management?

BACKGROUND

A mesh-related intestinal fistula is an uncommon and challenging complication of ventral hernia repair. Optimal management is unclear owing to lack of prospective or long-term data.

METHODS

We reviewed our prospective data for mesh-related intestinal fistulas from 2004 to 2017and compared suture repair versus ventral hernia repair with mesh at the time of mesh-related intestinal fistula takedown.

RESULTS

Eighty-two mesh-related intestinal fistulas were treated; none of the fistulas had closed spontaneously, and all fistula persisted at the time of our treatment. Mean age was 61 ± 12 years with 33-month follow-up. Comorbidities were similar between groups. Defects were 2.5-times larger in ventral hernia repair with mesh (324 ± 392 cm² vs 1301 ± 133 cm²; P = .044). Components separation (64% vs 21%; P = .0003) and panniculectomy (35% vs 7%; P = .0074) were more common in ventral hernia repair with mesh. Mortality occurred in 4 patients. Complications were similar. In patients undergoing ventral hernia repair with non-bridged, acellular, porcine dermal matrix, hernia recurrence was less than in patients without mesh (26% vs 66%; P = .0030). Only partial excision of the mesh involved with the fistula resulted in a substantial increase in developing another fistula (29% vs 6%; P < .05).

CONCLUSION

Patients undergoing preperitoneal ventral hernia repair with mesh for mesh-related intestinal fistula had a lesser rate of hernia recurrence and similar complications compared to suture repair despite larger hernias. Complete mesh excision decreases the risk of fistula recurrence. We maintain that ventral hernia repair with mesh during mesh-related intestinal fistula takedown represents the best opportunity for a durable herniorrhaphy.

When the Mesh Goes Away: An Analysis of Poly-4-Hydroxybutyrate Mesh for Complex Hernia Repair

Mesh reinforcement is a cornerstone of modern ventral hernia repair (VHR); yet, complications with synthetic mesh and cost of biologic have created a need for alternative options. Biosynthetic mesh is a resorbable scaffold that theoretically leverages the benefits and minimizes deficiencies of existing mesh types. This study evaluates 2-year outcomes following poly-4-hydroxybutyrate (P4HB) mesh reinforcement for complex VHR.

Methods

A retrospective review of all consecutive VHR with P4HB (n = 70) was conducted from 2015 to 2018 by a single surgeon. Clinical outcomes, quality of life (QoL; and cost were assessed.

Results

Seventy patients were included with an average age and body mass index of 58.6 years and 33 kg/m², respectively. High-risk comorbidities included hypertension (59%), and smoking history (50%). Cases were primarily modified Ventral Hernia Working Group class 2 (50%), or 3 (36%), with average defect size of 323 cm² (25-972 cm²). P4HB was placed in the retromuscular (80%) or onlay (20%) plane. Mean follow-up was 24 months (12.2-41 months). Hernia recurrence rate was 5.7% (n = 4) and occurred an average of 285 days (209-368 days) post-repair. Of the 21 surgical site occurrences (SSO), 5 (7%) required surgical intervention. A significant improvement in overall QoL (P = 0.001) was noted following repair. Defect size and SSOPI were independently associated with increased direct cost.

Conclusions

P4HB mesh for complex VHR is associated with favorable 2-year clinical outcomes, acceptable hernia recurrence rate, and a significant improvement in QoL. This study supports the use of biosynthetic mesh as an effective biomaterial for complex VHR.

Hernia recurrence and infection rate in elective complex abdominal wall repair using biologic mesh

Background

Elective complex ventral hernia repairs, done using synthetic mesh in patients with comorbidities, can result in mesh related complications such as hernia recurrence or infection. We studied hernia recurrence and surgical site occurrences after elective complex repairs in predominately clean cases using biologic mesh and examined the impact of several comorbidities.

Methods

A retrospective chart review was completed on patients who underwent elective repair with biologic mesh in clean/clean-contaminated settings between 2012 and 2015 with a minimum of 1-year follow-up. Multiple comorbid conditions, including diabetes, chronic obstructive pulmonary disease, steroid use, smoking history and previous hernia repairs were identified. Post-operative complications including recurrence and infections were ruled out by computed tomography, clinical exam, and/or by telephone survey.

Results

40 patients were identified. 85% (n = 34) had class 1 wounds. 25% (n = 10) experienced a hernia recurrence. 10% (n = 4) of patients developed postoperative infection, none required mesh explantation or re-operation. No statistically significant association was found between the comorbidities assessed and recurrence/infection rates.

Conclusions

We present the first study analyzing clinical outcomes of complex ventral hernia repairs using biologic mesh in predominately clean settings. This study being non-comparative limits definitive conclusions, but our aim is to add to the growing literature on biologic mesh to help future researchers performing comparative trials of synthetic versus biologic meshes.