Development of a novel murine model for treatment of infected mesh scenarios

Outcomes of Immediate Multistaged Abdominal Wall Reconstruction of Infected Mesh: Predictors of Surgical Site Complications and Hernia Recurrence

BACKGROUND

Mesh infection is one of the most devastating complications after ventral hernia repair. To date, no clear consensus exists on the optimal timing of definitive abdominal wall reconstruction (AWR) after excision of infected mesh. We evaluated outcomes of immediate multistaged AWR in patients with mesh infection.

METHODS

We performed a retrospective review of patients with mesh infection who underwent immediate, multistaged AWR, which consisted of exploratory laparotomy with debridement and mesh explantation, followed by definitive AWR during the same admission. Primary outcomes included hernia recurrence and surgical site occurrences, defined as wound dehiscence, surgical site infection, hematoma, and seroma.

RESULTS

Forty-seven patients with infected mesh were identified. At mean follow-up of 9.5 months, 5 patients (10.6%) experienced hernia recurrence. Higher body mass index (P = 0.006), bridge repair (P = 0.035), and postoperative surgical site infection (P = 0.005) were associated with hernia recurrence.

CONCLUSION

Immediate multistaged AWR is an effective surgical approach in patients with infected mesh.

Predictors for surgical site infection in patients undergoing therapeutic or prophylactic intra-abdominal onlay mesh (IPOM) implantation in clean and contaminated surgical fields

BACKGROUND

Prophylactic intra-abdominal onlay mesh (IPOM) implantation has been shown to reduce the rate of fascial dehiscence and incisional hernia. However, surgical site infection (SSI) in presence of an IPOM remains a concern. The aim of this study was to assess predictors for SSI following IPOM placement in hernia and non-hernia abdominal surgery in clean and contaminated surgical fields.

METHODS

Observational study including patients undergoing IPOM placement at a Swiss tertiary care hospital 2007-2016. IPOM implantation was performed in hernia and non-hernia elective and emergency abdominal surgery, including contaminated and infected surgical fields. The incidence of SSI was prospectively assessed by Swissnoso according to CDC criteria. The effect of disease- and procedure-related factors on SSI was assessed in multivariable regression analysis, adjusting for patient-related factors.

RESULTS

A total of 1072 IPOM implantations were performed. Laparoscopy was performed in 415 patients (38.7%), laparotomy in 657 patients (61.3%). SSI occurred in 172 patients (16.0%). Superficial, deep, and organ space SSI were found in 77 (7.2%), 26 (2.4%), and 69 (6.4%) patients, respectively. Multivariable analysis revealed emergency hospitalization (OR 1.787, p = 0.006), previous laparotomy (1.745, p = 0.029), duration of operation (OR 1.193, p < 0.001), laparotomy (OR 6.167, p < 0.001), bariatric (OR 4.641, p < 0.001), colorectal (OR 1.941, p = 0.001), and emergency (OR 2.510, p < 0.001) surgery, wound class ≥ 3 (OR 3.878, p < 0.001), and non-polypropylene mesh (OR 1.818, p = 0.003) as independent predictors for SSI. Hernia surgery was independently associated with a lower risk for SSI (OR 0.165, p < 0.001).

CONCLUSION

This study revealed emergency hospitalization, previous laparotomy, duration of operation, laparotomy, as well as bariatric, colorectal, and emergency surgery, abdominal contamination or infection, and usage of non-polypropylene mesh as independent predictors for SSI. In contrast, hernia surgery was associated with a lower risk for SSI. The knowledge of these predictors will help to balance benefits of IPOM implantation against the risk for SSI.

Effectiveness of Prophylactic Intraperitoneal Mesh Implantation for Prevention of Incisional Hernia in Patients Undergoing Open Abdominal Surgery: A Randomized Clinical Trial

Importance

Incisional hernia is a frequent complication after open abdominal surgery. Prophylactic mesh implantation in the onlay or sublay position requires dissection of the abdominal wall, potentially leading to wound-associated complications.

Objective

To compare the incidence of incisional hernia among patients after prophylactic intraperitoneal mesh implantation with that among patients after standard abdominal closure.

Design, Setting, and Participants

An open-label randomized clinical trial was performed in 169 patients undergoing elective open abdominal surgery from January 1, 2011, to February 29, 2014. Follow-up examinations were performed 1 year and 3 years after surgery. The study was conducted at Bern University Hospital, Bern, Switzerland, a referral center that offers the whole spectrum of abdominal surgical interventions. Patients with 2 or more of the following risk factors were included: overweight or obesity, diagnosis of neoplastic disease, male sex, or history of previous laparotomy. Patients were randomly assigned to prophylactic intraperitoneal mesh implantation or standard abdominal closure. Data were analyzed in August 2017.

Interventions

Intraperitoneal implantation of a polypropylene-polyvinylidene fluoride mesh with circumferential fixation.

Main Outcomes and Measures

The primary end point was the incidence of incisional hernia 3 years after surgery. Secondary end points included mesh-related complications.

Results

After the exclusion of 19 patients, 150 patients (81 in the control group and 69 in the mesh group; mean [SD] age, 64.2 [11.1] years; 102 [68.0%] male) were studied. The cumulative incidence of incisional hernia was significantly lower in the mesh group compared with the control group (5 of 69 [7.2%] vs 15 of 81 [18.5%], log-rank test P = .03). Abdominal pain was observed in significantly more patients in the mesh group compared with the control group at 6 weeks (34 of 52 [65%] vs 26 of 59 [44%], P = .04) but not at 12 and 36 months postoperatively. No difference in surgical site infections was observed, but time to complete wound healing of surgical site infection was significantly longer in patients with mesh implantation (median [interquartile range], 8 [6-24] weeks compared with 5 [1-9] weeks; P = .03). Trunk extension was significantly decreased after mesh implantation compared with the control group (mean [SD], 1.73 [0.97] cm vs 2.40 [1.23] cm, P = .009).

Conclusions and Relevance

In patients at elevated risk for incisional hernia, prophylactic intraperitoneal mesh implantation reduces the incidence of hernia formation but with increased early postoperative pain and prolonged wound healing of surgical site infection.

Trial Registration

ClinicalTrials.gov Identifier: NCT01203553.

A critical review of the in vitro and in vivo models for the evaluation of anti-infective meshes

BACKGROUND

Infectious complications following mesh implantation for abdominal wall repair appear in 0.7 up to 26.6% of hernia repairs and can have a detrimental impact for the patient. To prevent or to treat mesh-related infection, the scientific community is currently developing a veritable arsenal of antibacterial meshes. The numerous and increasing reports published every year describing new technologies indicate a clear clinical need, and an academic interest in solving this problem. Nevertheless, to really appreciate, to challenge, to compare and to optimize the antibacterial properties of next generation meshes, it is important to know which models are available and to understand them.

PURPOSE

We proposed for the first time, a complete overview focusing only on the in vitro and in vivo models which have been employed specifically in the field of antibacterial meshes for hernia repair.

RESULTS AND CONCLUSION

From this investigation, it is clear that there has been vast progress and breadth in new technologies and models to test them. However, it also shows that standardization or adoption of a more restricted number of models would improve comparability and be a benefit to the field of study.

Prophylactic, Synthetic Intraperitoneal Mesh Versus No Mesh Implantation in Patients with Fascial Dehiscence

BACKGROUND

Primary closure of post-operative facial dehiscence (FD) is associated with a high incidence of recurrence, revisional surgery, and incisional hernia. This retrospective study compares outcomes of implantation of non-absorbable intra-abdominal meshes with primary closure of FD. The outcomes of different mesh materials were assessed in subgroup analysis.

METHODS

A total of 119 consecutive patients with FD were operated (70 mesh group and 49 no mesh group) between 2001 and 2015. Primary outcome parameter was hernia-free survival. Secondary outcome parameters include re-operations of the abdominal wall, intestinal fistula, surgical site infections (SSI), and mortality. Kaplan-Meier analysis for hernia-free survival, adjusted Poisson regression analysis for re-operations and adjusted regression analysis for chronic SSI was performed.

RESULTS

Hernia-free survival was significantly higher in the mesh group compared to the no mesh group (P = 0.005). Fewer re-operations were necessary in the mesh group compared to the no mesh group (adjusted incidence risk ratio 0.44, 95% confidence interval [CI] 0.20-0.93, P = 0.032). No difference in SSI, intestinal fistula, and mortality was observed between groups. Chronic SSI was observed in 7 (10%) patients in the mesh group (n = 3 [6.7%] with polypropylene mesh and 4 [28.6%] with polyester mesh). The risk for chronic SSI was significantly higher if a polyester mesh was used when compared to a polypropylene mesh (adjusted odds ratio 8.69, 95% CI 1.30-58.05, P = 0.026).

CONCLUSION

Implantation of a polypropylene but not polyester-based mesh in patients with FD decreases incisional hernia with a low rate of mesh-related morbidity.