External validation of the ventral hernia risk score for prediction of surgical site infections

The association of hernia-specific and procedural risk factors with early complications in ventral hernia repair: ACHQC analysis

BACKGROUND

Many surgical risk assessment tools emphasize patient-specific risk factors. Our objective was to use a hernia-specific database to assess risk factors of complications in ventral hernia repair (VHR) focusing on hernia-specific and procedural factors.

METHODS

The ACHQC database was queried for elective VHR in adults from 2012 to 2023. Primary outcome was overall 30-day complications. Multivariable logistic regression was used for analysis.

RESULTS

41,526 VHR were included. The rate of 30-day complications was 18%, surgical site infection 3%, surgical site occurrence requiring procedural intervention 4%, readmission 4%, reoperation 2%, and mortality 0.2%. Multivariable analysis demonstrated that BMI, ASA, frailty, COPD, anticoagulants, defect width, incisional and recurrent hernias, presence of stoma or prior mesh, prior abdominal wall infection, non-clean wound, operative time, open approach and myofascial release were associated with 30-day complications (OR ​= ​1.01-1.66). Preoperative chlorhexidine, bowel preparation and fascial closure were associated with lower complication risk (OR ​= ​0.70-0.89).

CONCLUSION

Hernia and procedural risk factors are associated with early complications following elective VHR. These factors need to be included in surgical risk assessment tools, to supplement patient-specific factors.

A Ventral Hernia Management Pathway; A "Getting It Right First Time" approach to Complex Abdominal Wall Reconstruction

INTRODUCTION

Abdominal wall reconstruction (AWR) is an emerging specialty, involving complex multi-stage operations in patients with high medical and surgical risk. At our hospital, we have developed a growing interest in AWR, with a commitment to improving outcomes through a regular complex hernia MDT. An MDT approach to these patients is increasingly recognized as the path forward in management to optimize patients and improve outcomes.

METHODS

We conducted a literature review and combined this with our experiential knowledge of managing these cases to create a pathway for the management of our abdominal wall patients. This was done under the auspices of GIRFT (Getting It Right First Time) as a quality improvement project at our hospital.

RESULTS

We describe, in detail, our current AWR pathway, including the checklists and information documents we use with a stepwise evidence and experience-based approach to identifying the multiple factors associated with good outcomes. We explore the current literature and discuss our best practice pathway.

CONCLUSION

In this emerging specialty, there is limited guidance on the management of these patients. Our pathway, the "Complex Hernia Bundle," currently provides guidance for our abdominal wall team and may well be one that could be adopted/adapted by other centers where challenging hernia cases are undertaken.

Risk Factor-Driven Prehabilitation Prior to Abdominal Wall Reconstruction to Improve Postoperative Outcome. A Narrative Review

All abdominal wall reconstructions find themselves on a scale, varying between simple to highly complex procedures. The level of complexity depends on many factors that are divided into patient comorbidities, hernia characteristics, and wound characteristics. Preoperative identification of modifiable risk factors provides the opportunity for patient optimization. Because this so called prehabilitation greatly improves postoperative outcome, reconstructive surgery should not be scheduled before all modifiable risk factors are optimized to a point where no further improvement can be expected. In this review, we discuss the importance of preoperative risk factor recognition, identify modifiable risk factors, and utilize options for patient prehabilitation, all aiming to improve postoperative outcome and therewith long-term success of the reconstruction.

Validation of ventral hernia risk score in predicting surgical site infections

PURPOSE

Ventral hernia risk score (VHRS) is a risk assessment tool for predicting the development of surgical site infection (SSI) developed in the Veterans Affairs population by Berger et al. The score was externally validated by the same study group in a diverse population in another study. It was also shown to be better than the existing Centre for Diseases (CDC) wound class and Ventral Hernia Working Group (VHWG) models. Our study aims to test the performance of the score in an Asian-Indian population.

METHODS

A prospective database of ventral hernia repairs done in a tertiary care centre between February 2019 and December 2020 was utilized for the study. All patients with a minimum follow-up of 1-month period were included in the study. The CDC definition of SSI was used. The VHRS, VHWG, and CDC class of each of the patients was determined. Receiver-Operating curves (ROC) of the scores and area under the curves (AUC) were used to compare the three scores.

RESULTS

A total of 120 patients were included. During the course of our study, a total of 33 patients developed SSI (27.5%). Important factors which seemed to predict SSI were median operating time, CDC incision class, concomitant hernia repair, and creating skin flaps. The AUC of the VHRS score was 0.76 which was higher than those of VHWG (0.61) and CDC (0.58).

CONCLUSION

Our study externally validates the novel VHRS which outperforms both CDC incision class and VHWG in predicting SSI following open ventral hernia repair, especially in a group with lower BMI compared to the previous reports. Trial registration No CTRI/2020/07/026289 registered on 01/07/2020.

Use of incisional preventive negative pressure wound therapy in open incisional hernia repair: Who benefits?

Complex surgery of abdominal wall hernia continues to bear the major concern of wound healing disorders. Technical modifications have not been able to sufficiently prevent wound healing impairments or infections, even in clean elective cases, especially when dealing with large-scale hernia defects. Incisional negative pressure wound therapy (iNPWT) in its intentional use as a preventive tool has recently found its way from theoretical and experimental advantages to the clinical routine. Different indications have been defined but evidence is lacking. We performed a retrospective analysis (1/2014-5/2019) of all ventral hernia repairs (n = 386) done in our institution as open sublay mesh reinforcement, partially requiring component separation (CS), receiving iNPWT in selected cases based on single surgeon experience. Pre- and perioperative data included patient and hernia characteristics as well as the employed mesh sizes. Postoperative follow-up (median 38.5 months [interquartile range: 23.4, 53.3]) extended beyond patient dismissal and included the rate of re-admission due to wound healing disorders. The primary outcome was the incidence of surgical site occurrences (SSO). Secondary endpoints included wound-related readmissions, reoperations and recurrences. Patients were matched based on propensity scores in a 1:1 ratio. Propensity scores were calculated based on five preoperative variables, including sex, body-mass-index, American Society of Anesthesiology classification, recurrent hernia repair and operation technique, to identify significant parameters. The rate of SSO was 12% (n = 46) for all operated cases, and the rate of surgical site infection (SSI) was 8.8% (n = 34). In the subgroup of CS (n = 40), the rate increased to 15% (n = 6). The usage of iNPWT (n = 54) led to an in-hospital SSO rate of 14.8% (n = 8) but increased to 33.3% (n = 18) when including the re-admission rate. The SSI rate for the iNPWT cohort was 14.8% (n = 8) with a consecutive need for reoperation (Clavien-Dindo IIIb) in 87.5% (n = 7). In the matched-pair analysis, the hernia-size and mesh-size were the main risk factors for SSO. The use of iNPWT significantly reduced this statistical effect (p = 0.405). In a large and representative patient cohort, we were able to demonstrate that the advantage of iNPWT used after complex abdominal wall repair does not come first hand. Especially in the follow-up, we found a relevant increase in wound healing problems after dismissal. To proof the benefit of iNPWT in these heterogeneous patients, we could identify hernia size and mesh size as individual risk factors that were nihilated by the use of iNPWT. We found it to be favourable to use iNPWT when mesh-size exceeded 450 cm² .

Delayed primary closure (DPC) of the skin and subcutaneous tissues following complex, contaminated abdominal wall reconstruction (AWR): a propensity-matched study

BACKGROUND

Wound complications following abdominal wall reconstruction (AWR) in a contaminated setting are common and significantly increase the risk of hernia recurrence. The purpose of this study was to examine the effect of short-term negative pressure wound therapy (NPWT) followed by operative delayed primary closure (DPC) of the skin and subcutaneous tissue after AWR in a contaminated setting.

METHODS

A prospective institutional hernia database was queried for patients who underwent NPWT-assisted DPC after contaminated AWR between 2008 and 2020. Primary outcomes included wound complication rate and reopening of the incision. A non-DPC group was created using propensity-matching. Standard descriptive statistics were used, and a univariate analysis was performed between the DPC and non-DPC groups.

RESULTS

In total, 110 patients underwent DPC following AWR. The hernias were on average large (188 ± 133.6 cm²), often recurrent (81.5%), and 60.5% required a components separation. All patients had CDC Class 3 (14.5%) or 4 (85.5%) wounds and biologic mesh placed. Using CeDAR, the wound complication rate was estimated to be 66.3%. Postoperatively, 26.4% patients developed a wound complication, but only 5.5% patients required reopening of the wound. The rate of recurrence was 5.5% with mean follow-up of 22.6 ± 27.1 months. After propensity-matching, there were 73 patients each in the DPC and non-DPC groups. DPC patients had fewer overall wound complications (23.0% vs 43.9%, p = 0.02). While 4.1% of the DPC group required reopening of the incision, 20.5% of patients in the non-DPC required reopening of the incision (p = 0.005) with an average time to healing of 150 days. Hernia recurrence remained low overall (2.7% vs 5.4%, p = 0.17).

CONCLUSIONS

DPC can be performed with a high rate of success in complex, contaminated AWR patients by reducing the rate of wound complications and avoiding prolonged healing times. In patients undergoing AWR in a contaminated setting, a NPWT-assisted DPC should be considered.

Polyester Mesh Functionalization with Nitric Oxide-Releasing Silica Nanoparticles Reduces Early Methicillin-Resistant Staphylococcus aureus Contamination

Background: Infected hernia mesh is a cause of post-operative morbidity. Nitric oxide (NO) plays a key role in the endogenous immune response to infection. We sought to study the efficacy of a NO-releasing mesh against methicillin-resistant Staphylococcus aureus (MRSA). We hypothesized that a NO-releasing polyester mesh would decrease MRSA colonization and proliferation. Materials and Methods: A composite polyester mesh functionalized with N-diazeniumdiolate silica nanoparticles was synthesized and characterized. N-diazeniumdiolate silica parietex composite (NOSi) was inoculated with 10⁴,10⁶, or 10⁸ colony forming units (CFUs) of MRSA and a dose response was quantified in a soy tryptic broth assay. Utilizing a rat model of contaminated hernia repair, implanted mesh was inoculated with MRSA, recovered, and CFUs were quantified. Clinical metrics of erythema, mesh contracture, and adhesion severity were then characterized. Results: Methicillin-resistant Staphylococcus aureus CFUs demonstrated a dose-dependent response to NOSi in vitro. In vivo, quantified CFUs showed a dose-dependent response to NOSi-PCO. Treated rats had fewer severe adhesions, less erythema, and reduced mesh contracture. Conclusions: We demonstrate the efficacy of a NO-releasing mesh to treat MRSA in vitro and in vivo. Creation of a novel class of antimicrobial prosthetics offers new strategies for reconstructing contaminated abdominal wall defects and other procedures that benefit from deploying synthetic prostheses in contaminated environments.

Definitions for Loss of Domain: An International Delphi Consensus of Expert Surgeons

BACKGROUND

No standardized written or volumetric definition exists for 'loss of domain' (LOD). This limits the utility of LOD as a morphological descriptor and as a predictor of peri- and postoperative outcomes. Consequently, our aim was to establish definitions for LOD via consensus of expert abdominal wall surgeons.

METHODS

A Delphi study involving 20 internationally recognized abdominal wall reconstruction (AWR) surgeons was performed. Four written and two volumetric definitions of LOD were identified via systematic review. Panelists completed a questionnaire that suggested these definitions as standardized definitions of LOD. Consensus on a preferred term was pre-defined as achieved when selected by ≥80% of panelists. Terms scoring <20% were removed.

RESULTS

Voting commenced August 2018 and was completed in January 2019. Written definition: During Round 1, two definitions were removed and seven new definitions were suggested, leaving nine definitions for consideration. For Round 2, panelists were asked to select all appealing definitions. Thereafter, common concepts were identified during analysis, from which the facilitators advanced a new written definition. This received 100% agreement in Round 3. Volumetric definition: Initially, panelists were evenly split, but consensus for the Sabbagh method was achieved. Panelists could not reach consensus regarding a threshold LOD value that would preclude surgery.

CONCLUSIONS

Consensus for written and volumetric definitions of LOD was achieved from 20 internationally recognized AWR surgeons. Adoption of these definitions will help standardize the use of LOD for both clinical and academic activities.

Hospital and surgeon variation in 30-day complication rates after ventral hernia repair

BACKGROUND

Ventral hernia repair is an extremely common operation, however the variability in patient outcomes between individual hospitals and surgeons is unclear. We analyzed variability in 30-day complication rates and identified specific complications that contributed to this variability.

METHODS

Retrospective, cross-sectional analysis of 30-day complication rates following ventral hernia repair across 73 hospital and 978 surgeons between January 1, 2014 and December 31, 2018.

RESULTS

Data were collected on 19,007 patients who underwent VIHR at 73 hospitals across 978 surgeons. Adjusted complication rate among hospitals was 6.2% (range 4.3%-12.8%) and among surgeons was 6.2% (range 3.5%-26.8%). Variation between lowest and highest quartile surgeons was greatest for acute kidney injury (0.12% vs. 1.71%, P < 0.001), superficial surgical site infection (0.33% vs. 3.62%, P < 0.001), sepsis (0.27% vs. 2.47%, P < 0.001), and catheter-associated urinary tract infection (0.02% vs. 0.30%, P < 0.001).

CONCLUSION

After adjusting for a number of patient-specific clinical variables, there is significant variation in 30-day complication rates after ventral hernia repair. This represents a significant opportunity to improve patient outcomes.

S116: Impact of incisional negative pressure wound therapy on surgical site infection after complex incisional hernia repair: a retrospective matched cohort study

INTRODUCTION

Incisional negative pressure wound therapy (iNPWT) may reduce surgical site infections (SSI), which can have devastating consequences after incisional hernia repair. Few comparative studies investigate the effectiveness of this wound management strategy in this population. The objective of this study is to determine the effect of iNPWT on the incidence of SSI after complex incisional hernia repair.

METHODS

All adult patients undergoing open incisional hernia repair at a single center from 2016 to 2019 were reviewed. A commercial iNPWT dressing was used at the discretion of the surgeon. Patients were grouped by type of dressing; iNPWT and standard sterile dressings (SSD). Coarsened exact matching was used to create balanced cohorts for comparison using age, sex, American Society of Anesthesiologists classification, wound classification, and surgical urgency. The primary outcome was the composite incidence of superficial and deep SSI within 30 days. Secondary outcomes included non-infectious surgical site occurrences (SSO), overall complications, length of stay (LOS), emergency department visits, and readmission at 30 days.

RESULTS

134 patients underwent complex hernia repair, with 114 patients included after matching (34 iNPWT, 51 SSD). Composite incidence of superficial and deep SSI was 19.3% (11.8% vs. 27.5%, p = 0.107), with significantly lower rates of deep SSI in patients receiving iNPWT (2.9% vs. 17.6%, p = 0.045). After accounting for residual differences between groups, iNPWT was associated with decreased incidence of composite SSI (RR 0.36, 95% CI [0.16, 0.87]). Median LOS was longer in patients with iNPWT (7 vs. 5 days, p = 0.001). There were no differences in SSO, overall complications, readmission, or emergency department visits.

CONCLUSION

In patients undergoing incisional hernia repair, the use of iNPWT was associated with a lower incidence of SSI at 30 days. Future studies should focus on cost effectiveness of iNPWT, its impact on long-term hernia recurrences, and the identification of patient selection criteria in this population.

Bridging repair of the abdominal wall in a rat experimental model. Comparison between uncoated and polyethylene oxide-coated equine pericardium meshes

Biological meshes improve the outcome of incisional hernia repairs in infected fields but often lead to recurrence after bridging techniques. Sixty male Wistar rats undergoing the excision of an abdominal wall portion and bridging mesh repair were randomised in two groups: Group A (N = 30) using the uncoated equine pericardium mesh; Group B (N = 30) using the polyethylene oxide (PEO)-coated one. No deaths were observed during treatment. Shrinkage was significantly less common in A than in B (3% vs 53%, P < 0.001). Adhesions were the most common complication and resulted significantly higher after 90 days in B than in A (90% vs 30%, P < 0.01). Microscopic examination revealed significantly (P < 0.05) higher mesh integrity, fibrosis and calcification in B compared to A. The enzymatic degradation, as assessed with Raman spectroscopy and enzyme stability test, affected A more than B. The PEO-coated equine pericardium mesh showed higher resistance to biodegradation compared to the uncoated one. Understanding the changes of these prostheses in a surgical setting may help to optimize the PEO-coating in designing new biomaterials for the bridging repair of the abdominal wall.

The development and validation of risk-stratification models for short-term outcomes following contaminated complex abdominal wall reconstruction

BACKGROUND

Short-term outcomes for patients undergoing contaminated complex abdominal wall reconstruction (CCAWR), including risk stratification, have not been studied in sufficiently high numbers. This study aims to develop and validate risk-stratification models for Clavien-Dindo (CD) grade ≥ 3 complications in patients undergoing CCAWR.

METHODS

A consecutive cohort of patients who underwent CCAWR in two European national intestinal failure centers, from January 2004 to December 2015, was identified. Data were collected retrospectively for short-term outcomes and used to develop risk models using logistic regression. A further cohort, from January 2016 to December 2017, was used to validate the models.

RESULTS

The development cohort consisted of 272 procedures performed in 254 patients. The validation cohort consisted of 114 patients. The cohorts were comparable in baseline demographics (mean age 58.0 vs 58.1; sex 58.8% male vs 54.4%, respectively). A multi-variate model including the presence of intestinal failure (p < 0.01) and operative time (p < 0.01) demonstrated good discrimination and calibration on validation. Models for wound and intra-abdominal complications were also developed, including pre-operative immunosuppression (p = 0.05), intestinal failure (p = 0.02), increasing operative time (p = 0.04), increasing number of anastomoses (p = 0.01) and the number of previous abdominal operations (p = 0.02). While these models showed reasonable ability to discriminate patients on internal assessment, they were not found to be accurate on external validation.

CONCLUSION

Acceptable short-term outcomes after CCAWR are demonstrated. A robust model for the prediction of CD ≥ grade 3 complications has been developed and validated. This model is available online at www.smbari.co.uk/smjconv2.

The Perth Surgical Wound Dehiscence Risk Assessment Tool (PSWDRAT): development and prospective validation in the clinical setting

OBJECTIVE

The worldwide volume of surgery today is considerable and postoperative wound healing plays a significant part in facilitating a patient's recovery and rehabilitation. While contemporary surgical procedures are relatively safe, complications such as surgical wound dehiscence (SWD) or breakdown of the incision site may occur despite advances in surgical techniques, infection control practices and wound care. SWD impacts on patient mortality and morbidity and significantly contributes to prolonged hospital stay. Preoperative identification of patients at risk of SWD may be valuable in reducing the risk of postoperative wound complications.

METHOD

A three-phase study was undertaken to determine risk factors associated with SWD, develop a preoperative patient risk assessment tool and to prospectively validate the tool in a clinical setting. Phases 1 and 2 were retrospective case control studies. Phase 1 determined variables associated with SWD and these informed the development of a risk assessment tool. Univariate analysis and multiple logistic regression were applied to identify predictors of surgical risk. Phase 2 used the receiver operator curve statistic to determine the predictive power of the tool. Phase 3 involved a prospective consecutive case series validation to test the inter-rater reliability and predictive power of the tool.

RESULTS

In addition to those already identified in the literature, one independent risk predictor for SWD was identified: previous surgery in the same anatomical location (p<0.001, odds ratio [OR] 4). Multiple combined factors were integrated into the tool and included: age (p<0.019, OR 3), diabetes (p<0.624, OR 2), obesity (p<0.94, OR 1.4), smoking (p<0.387, OR 2), cardiovascular disease (p<0.381 OR 3) and peripheral arterial disease (p<0.501, OR 3). The predictive power of the tool yielded 71% in a combined data sample.

CONCLUSION

Patients with previous surgery in the same anatomical location were four times more likely to incur a dehiscence. Identification of at-risk patients for complications postoperatively is integral to reducing SWD occurrence and improving health-related outcomes following surgery.

Prophylactic antibiotic bundle compliance and surgical site infections: an artificial neural network analysis

Background

Best practice "bundles" have been developed to lower the occurrence rate of surgical site infections (SSI's). We developed artificial neural network (ANN) models to predict SSI occurrence based on prophylactic antibiotic compliance.

Methods

Using the American College of Surgeons National Quality Improvement Program (ACS-NSQIP) Tampa General Hospital patient dataset for a six-month period, 780 surgical procedures were reviewed for compliance with SSI guidelines for antibiotic type and timing. SSI rates were determined for patients in the compliant and non-compliant groups. ANN training and validation models were developed to include the variables of age, sex, steroid use, bleeding disorders, transfusion, white blood cell count, hematocrit level, platelet count, wound class, ASA class, and surgical antimicrobial prophylaxis (SAP) bundle compliance.

Results

Overall compliance to recommended antibiotic type and timing was 92.0%. Antibiotic bundle compliance had a lower incidence of SSI's (3.3%) compared to the non-compliant group (8.1%, p = 0.07). ANN models predicted SSI with a 69-90% sensitivity and 50-60% specificity. The model was more sensitive when bundle compliance was not used in the model, but more specific when it was. Preoperative white blood cell (WBC) count had the most influence on the model.

Conclusions

SAP bundle compliance was associated with a lower incidence of SSI's. In an ANN model, inclusion of the SAP bundle compliance reduced sensitivity, but increased specificity of the prediction model. Preoperative WBC count had the most influence on the model.

The reality of general surgery training and increased complexity of abdominal wall hernia surgery

INTRODUCTION

The Accreditation and Certification of Hernia Centers and Surgeons (ACCESS) Group of the European Hernia Society (EHS) recognizes that there is a growing need to train specialist abdominal wall surgeons. The most important and relevant argument for this proposal and statement is the growing acceptance of the increasing complexity of abdominal wall surgery due to newer techniques, more challenging cases and the required 'tailored' approach to such surgery. There is now also an increasing public awareness with social media, whereby optimal treatment results are demanded by patients. However, to date the complexity of abdominal wall surgery has not been properly or adequately defined in the current literature.

METHODS

A systematic search of the available literature was performed in May 2019 using Medline, PubMed, Scopus, Embase, Springer Link, and the Cochrane Library, with 75 publications identified as relevant. In addition, an analysis of data from the Herniamed Hernia Registry was performed. The percentage of patients with hernia- or patient-related characteristics which unfavorably impacted the outcome of inguinal and incisional hernia repair was also calculated.

RESULTS

All present guidelines for abdominal wall surgery recommend the utilization of a 'tailored' approach. This relies on the prerequisite that any surgical technique used has already been mastered, as well as the recognized learning curves for each of the several techniques that can be used for both inguinal hernia (Lichtenstein, TEP, TAPP, Shouldice) and incisional hernia repairs (laparoscopic IPOM, open sublay, open IPOM, open onlay, open or endoscopic component separation technique). Other hernia- and patient-related characteristics that have recognized complexity include emergency surgery, obesity, recurrent hernias, bilateral inguinal hernias, groin hernia in women, scrotal hernias, large defects, high ASA scores, > 80 years of age, increased medical risk factors and previous lower abdominal surgery. The proportion of patients with at least one of these characteristics in the Herniamed Hernia Registry in the case of both inguinal and incisional hernia is noted to be relatively high at around 70%. In general surgery training approximately 50-100 hernia repairs on average are performed by each trainee, with around only 25 laparo-endoscopic procedures.

CONCLUSION

A tailored approach is now employed and seen more so in hernia surgery and this fact is referred to and highlighted in the contemporaneous hernia guidelines published to date. In addition, with the increasing complexity of abdominal wall surgery, the number of procedures actually performed by trainees is no longer considered adequate to overcome any recognized learning curve. Therefore, to supplement general surgery training young surgeons should be offered a clinical fellowship to obtain an additional qualification as an abdominal wall surgeon and thus improve their clinical and operative experience under supervision in this field. Practicing general surgeons with a special interest in hernia surgery can undertake intensive further training in this area by participating in clinical work shadowing in hernia centers, workshops and congresses.

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

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

Polyester vs polypropylene, do mesh materials matter? A meta-analysis and systematic review

Purpose

Controversy exists regarding the outcomes following ventral hernia repair with polypropylene (PP) or polyester (PET) mesh. Monofilament PP less frequently requires extraction in the setting of contamination compared to multifilament PET mesh. The purpose of this systematic review and meta-analysis was to analyze the clinical outcomes of ventral hernia repair with PP and PET mesh.

Patients and methods

A comprehensive literature search was performed using the Ovid search platform. Criteria included ventral hernia repair publications using either PP or PET mesh with a minimum follow-up duration of one year. Included studies were subject to data extraction including mesh position, weight, recurrence rates, infection, and complications. Random effect meta-analysis was run to provide pooled event rate and 95% CI.

Results

Ninety-seven studies including a total of 10,022 patients were included in the final analysis. Hernia recurrence rates are similar (4.8%, 95% CI [3.5–6.5] vs 4.7%, 95% CI [3.7–6.0]) as well as mesh infection rates (3.5%, 95% CI [2.5–4.9] vs 5.0%, 95% CI [3.9–6.3]) between PET and PP, respectively. Mesh infections occurred less frequently in laparoscopic repair compared to open (1.6%, 95% CI [0.9–2.6] vs 5.2%, 95% CI [4.3–6.3]).

Conclusion

This study suggests that mesh material does not affect recurrence or infection in ventral hernia repair and that surgery can be safely performed with both PP and PET mesh. A laparoscopic approach is associated with a decreased infection rate compared to open repair independent of mesh type.

Prevention of patch infection after abdominal external hernia repair

External abdominal hernia is a common clinical disease. The application of hernia patch is a breakthrough in the treatment of external abdominal hernia. However, complications such as patch infection need to be solved urgently. Patch infection markedly prolongs the hospitalization time and increases the medical expenses of patients. At present, a standard method for the diagnosis, treatment, and prevention of patch infection remains to be developed. This paper summarizes the literature in recent years to explore the research progress in the prevention and treatment of patch infection.

Control of body temperature and immune function in patients undergoing open surgery for gastric cancer

The influence of mild perioperative hypothermia on the immune function and incidence of postoperative wound infections has been suggested, but the specific mechanism is unclear. This study aimed to analyze the body temperature, immune function, and wound infection rates in patients receiving open surgery for gastric cancer. Body temperature was controlled in each patient using one of four different methods: wrapping limbs, head and neck; insulated blankets; warming infusion fluids and insulated blankets; and warming fluids without insulated blankets. One hundred patients were randomly divided into four groups of 25 patients each, and every group received a different intraoperative treatment for maintaining normal body temperature. Nasopharyngeal and rectal temperatures, transforming growth factor beta (TGF-β), interleukin 10 (IL-10) levels, and cluster of differentiation (CD)3+T and CD4+/CD25+ regulatory T cell (Treg) counts were measured before surgery and at 2 and 4 hours postoperatively. Patients were evaluated at one week after surgery for signs of infection. Intraoperative body temperature and measures of immune function varied significantly between the four groups, with the largest temperature changes observed in the group in which only the limbs were wrapped in cotton pads to control the body temperature. The lowest temperature change (i.e., close to normal temperature) and cytokine response after surgery were observed in the group in which infusion fluids and transfused blood (if needed) were heated to 37℃, peritoneal irrigation fluid was heated to 37℃, and an insulation blanket was heated to 39℃ and placed under the patient. No intergroup differences were found in the infection rates at one week after surgery. In conclusion, body temperature variation during surgery affects the immune function of patients, and maintaining body temperature close to normal results in the least variation of immune function.

Professional fee payments by specialty for inpatient open ventral hernia repair: who gets paid for treating comorbidities and complications?

BACKGROUND

The purpose of this study was to determine perioperative professional fee payments to providers from different specialties for the care of patients undergoing inpatient open ventral hernia repair (VHR).

METHODS

Perioperative data of patients undergoing VHR at a single center over 3 years were selected from our NSQIP database. 180-day follow-up data were obtained via retrospective review of records and phone calls to patients. Professional fee payments (PFPs) to all providers were obtained from our physician billing system for the VHR hospitalization, the 180 days prior to operation (180Prior) and the 180 days post-discharge (180Post).

RESULTS

PFPs for 283 cases were analyzed. Average total 360-day PFPs per patient were $3409 ± SD 3294, with 14.5% ($493 ± 1546) for services in the 180Preop period, 72.5% ($2473 ± 1881) for the VHR hospitalization, and 13.0% ($443 ± 1097) in the 180Postop period. The surgical service received 62% of PFPs followed by anesthesia (18%), medical specialties (9%), radiology (6%), and all other provider services (5%). Medical specialties received increased PFPs for care of patients with COPD and HCT < 38% ($90 and $521, respectively) and for the pulmonary complications ($2471) and sepsis ($2714) that correlated with those patient comorbidities; surgeons did not. Operative duration, mesh size, and separation of components were associated with increased surgeon PFPs (p < .05). At 6 months, wound complications were associated with increased surgeon and radiology payments (p < .01).

CONCLUSIONS

Management of acute comorbid conditions and the associated higher postoperative morbidity is not reimbursed to the surgeon under the 90-day global fee. These represent opportunity costs of care that pressure busy surgeons to select against these patients or to delegate more management to their medical specialty colleagues, thereby increasing total system costs. A comorbid risk adjustment of procedural reimbursement is warranted. In negotiating bundled payments, surgeon groups should keep in mind that surgeon reimbursement, unlike medical specialty and hospital reimbursement, have been bundled since the 1990s.

Outcomes after Ventral Hernia Repair Using the Rives-Stoppa, Endoscopic, and Open Component Separation Techniques

Complex ventral hernias remain a challenge for general surgeons despite advances in minimally invasive surgical techniques. This study compares outcomes following Rives-Stoppa (RS) repair, components separation technique with mesh (CST-M) or without mesh (CST), and endoscopic components separation technique (ECST). A retrospective review of patients undergoing open ventral hernia repair between 2006 and 2011 was performed. Analysis included patient demographics, surgical site occurrences, hernia recurrence, hospital readmission, and mortality. The search was limited to open repairs, specifically the RS, CST-M, CST, and ECST with mesh techniques. A total of 362 patients underwent repair with RS (66), CST-M (126), CST (117), or ECST (53). The groups were demographically similar. ECST was more frequently used for patients with a history of two or more recurrences ( P < 0.001). The RS method had the lowest rate of recurrence (9.1%) compared with CST and CST-M with 28 and 25 per cent recurrences, respectively ( P = 0.011). The RS recurrence rate was not significantly different than ECST (15%). There were no significant differences between groups for surgical site occurrences ( P = 0.305), hospital read-mission ( P = 0.288), or death ( P = 0.197). When components separation is necessary for complex ventral hernia repair, ECST is a viable option without added morbidity or mortality.

Impact of Surgical Site Infections on Elective Incisional Hernia Surgery: A Prospective Study

BACKGROUND

Although incisional hernia repair is classified as a clean surgery, it still has a high incidence of surgical site infection (SSI) (0.7%-26.6%). The presence of an SSI could increase early recurrence rates after incisional hernia repair.

PATIENTS AND METHODS

Patients undergoing elective incisional hernia repair with no bowel contamination between January and December 2015 were assessed prospectively. Demographic and surgical data, local post-operative complications, and one-year recurrence rates in patients with and without SSI were compared. The management of SSI was determined.

RESULTS

Patients with SSI (16/101) showed more prolonged surgical procedures (91 ± 39 vs. 63 ± 30 min, p = 0.012), more post-operative sero-hematomas (38% vs. 8%, p = 0.001), and a higher one-year recurrence rate (19% vs. 4%, p = 0.047). Multivariable analysis revealed the only identified risk factor for SSI to be post-operative sero-hematomas (p = 0.042; odds ratio [OR] = 4.17 [1.05-16.54]). Patients who developed an SSI required antibiotic agents and daily treatment from one to five months. One of these required the removal of the mesh.

CONCLUSIONS

Surgical site infection rates are high for incisional hernia surgery (16%), and associated with local complications. Surgical site infection requires long-term treatments and leads to a higher one-year recurrence rate.

Early outcomes of an enhanced recovery protocol for open repair of ventral hernia

BACKGROUND

Enhanced recovery after surgery (ERAS) protocols are evidence-based quality improvement pathways reported to be associated with improved patient outcomes. The purpose of this study was to compare short-term outcomes for open ventral hernia repair (VHR) before and after implementation of an ERAS protocol.

METHODS

After obtaining IRB approval, surgical databases were searched for VHR cases for two years prior and eleven months after protocol implementation for retrospective review. Groups were compared on perioperative characteristics and clinical outcomes using chi-square, Fisher's exact, or Mann-Whitney U test, as appropriate.

RESULTS

One hundred and seventy-one patients underwent VHR (46 patients with ERAS protocol in place and 125 historic controls). Age, gender, ASA Class, comorbidities, and smoking status were similar between the two groups. Body mass index was lower among ERAS patients (p = .038). ERAS patients had earlier return of bowel function (median 3 vs. 4 days) (p = .003) and decreased incidence of superficial surgical site infection (SSI) (7 vs. 25%) (p = .008) than controls.

CONCLUSION

An ERAS protocol for VHR demonstrated improved patient outcomes. A system-wide culture focused on enhanced recovery is needed to ensure improved patient outcomes.

Current Risk Stratification Systems Are Not Generalizable across Surgical Technique in Midline Ventral Hernia Repair

Background:

Current ventral hernia repair risk estimation tools focus on patient comorbidities with the goal of improving clinical outcomes through improved patient selection. However, their predictive value remains unproven.

Methods:

Outcomes of patients who underwent midline ventral hernia repair with retrorectus placement of mid-weight soft polypropylene mesh between 2010 and 2015 were retrospectively reviewed and compared with predicted wound-related complication risk from 3 tools in the literature: Carolinas Equation for Determining Associated Risk, the Ventral Hernia Working Group (VHWG) grade, and a modified VHWG grade.

Results:

A total of 101 patients underwent hernia repair. Mean age was 56 years and mean body mass index was 29 m/kg² (range, 18–51 m/kg²). We found no significant relationship between the risk estimated by Carolinas Equation for Determining Associated Risk (B = 1.45, P = 0.61) and actual wound-related complications. VHWG grades >1 were not statistically different with regard to rate of wound complication compared with VHWG grade 1 (grade 2: B = 0.05, P = 0.95; grade 3: B = −0.21, P = 0.86; grade 4: B = 2.57, P = 0.10). Modified VHWG grades >1 were not statistically different with regard to rate of wound complication compared with modified VHWG grade 1 (grade 2: B = 0.20, P = 0.80; grade 3: B = 1.03, P = 0.41).

Conclusions:

Current risk stratification tools overemphasize patient factors, ignoring the importance of technique in minimizing complications and recurrence. We attribute our low complication rate to retrorectus placement of a narrow, macroporous polypropylene mesh with up to 45 suture fixation points for force distribution in contrast to current strategies that employ wide meshes with minimal fixation.

Complex Ventral Hernia Repair with Acellular Dermal Matrices: Clinical and Quality of Life Outcomes

Acellular dermal matrices (ADMs) are used in conjunction with complex hernia repair, but their efficacy is often debated. This study assesses clinical and quality of life (QOL) outcomes in multiply comorbid patients undergoing complex ventral hernia repair using ADMs. After obtaining institutional review board approval, a prospective study was conducted evaluating patients undergoing complex ventral incisional hernia repair with abdominal wall reconstruction (AWR) using either human (Flex HD) or porcine ADM (Strattice). Patient accrual occurred over three years. Demographics, comorbid conditions, and operative details were recorded. Postoperative two-week, six-week, six-month, and one-year follow-up occurred. Primary outcomes measures include wound occurrence, QOL parameters using the Short Form-12 health survey, and hernia recurrence. Groups were compared using chi-squared, Fisher's exact, Mann-Whitney U, or t tests as appropriate. Significance was set at P < 0.05. Thirty-five patients underwent hernia repair using ADM: mean age = 58 years, mean body mass index = 34 kg/m2, >50 per cent Centers for Disease Control and Prevention Wound Class II and above, >50 per cent recurrent hernia repair, and 25 per cent current or previous mesh infection. Twenty patients (57%) experienced surgical site occurrences, 15 (43%) wound infections, and 5 (14%) recurrences with a median follow-up of one year. All Short Form-12 QOL indicators improved at 12 months compared with baseline (NS). Outcomes were similar between mesh types. In conclusion, abdominal wall reconstruction for complex hernias using biologic materials is safe but has significant morbidity. Wound complications occur in over half of all patients and are not impacted by ADM type. There is no decrement in QOL one year after hernia repair despite associated morbidity.

Ventral and incisional hernia: the cost of comorbidities and complications

INTRODUCTION

Ventral and incisional hernia repair (VIHR) is among the most frequently performed abdominal operations with significant incidence of postoperative complications and readmissions. Payers are targeting increased "value" of care through improved outcomes and reduced costs. Cost data in clinically relevant terms is still rare. This study aims to identify hospital costs associated with clinically relevant factors in order to facilitate strategies by surgeons to enhance the value of VIHR.

METHODS

An IRB-approved retrospective review of VIHRs performed at the University of Kentucky from April 2009 through September 2013 was conducted. NSQIP clinical data and hospital cost data were matched. Operating room (ORC), total encounter (TEC), and 90-day postdischarge (90PDC) hospital costs were analyzed relative to clinical variables using non-parametric tests.

RESULTS

In total 385 patients that underwent VIHR during the time period were included in the analyses. Considering all VIHRs, median [interquartile range (IQR)] ORC was $6900 ($5600-$10,000); TEC was $10,700 ($7500-$18,600); and 90PDC was $0 ($0-$800). Compared to all VIHRs, ASA Class ≥ 3 was associated with increased ORC and TEC (p < .001), and 90PDC (p < .01). Preoperative open wound was associated with increased ORC and TEC (p < .001). Numerous operative variables were associated with both increased ORC and TEC. Wound Class > 1 was associated with increased ORC and TEC (p < .001) and 90PDC (p < .01). Inpatient occurrence of any complication was associated with increased TEC and 90PDC (p < .001).

CONCLUSIONS

ASA Class ≥ 3, Wound Class > 1, open abdominal wound, and postoperative complications significantly increase costs. Although the hospital encounter represents the majority of the cost associated with VIHR, additional costs are incurred during the 90-day postoperative period. An appreciation of global costs is essential in developing alternative payment models for hernia in order to provide the greatest value in hernia care.

Do risk calculators accurately predict surgical site occurrences?

INTRODUCTION

Current risk assessment models for surgical site occurrence (SSO) and surgical site infection (SSI) after open ventral hernia repair (VHR) have limited external validation. Our aim was to determine (1) whether existing models stratify patients into groups by risk and (2) which model best predicts the rate of SSO and SSI.

METHODS

Patients who underwent open VHR and were followed for at least 1 mo were included. Using two data sets-a retrospective multicenter database (Ventral Hernia Outcomes Collaborative) and a single-center prospective database (Prospective)-each patient was assigned a predicted risk with each of the following models: Ventral Hernia Risk Score (VHRS), Ventral Hernia Working Group (VHWG), Centers for Disease Control and Prevention Wound Class, and Hernia Wound Risk Assessment Tool (HW-RAT). Patients in the Prospective database were also assigned a predicted risk from the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP). Areas under the receiver operating characteristic curve (area under the curve [AUC]) were compared to assess the predictive accuracy of the models for SSO and SSI. Pearson's chi-square was used to determine which models were able to risk-stratify patients into groups with significantly differing rates of actual SSO and SSI.

RESULTS

The Ventral Hernia Outcomes Collaborative database (n = 795) had an overall SSO and SSI rate of 23% and 17%, respectively. The AUCs were low for SSO (0.56, 0.54, 0.52, and 0.60) and SSI (0.55, 0.53, 0.50, and 0.58). The VHRS (P = 0.01) and HW-RAT (P < 0.01) significantly stratified patients into tiers for SSO, whereas the VHWG (P < 0.05) and HW-RAT (P < 0.05) stratified for SSI. In the Prospective database (n = 88), 14% and 8% developed an SSO and SSI, respectively. The AUCs were low for SSO (0.63, 0.54, 0.50, 0.57, and 0.69) and modest for SSI (0.81, 0.64, 0.55, 0.62, and 0.73). The ACS-NSQIP (P < 0.01) stratified for SSO, whereas the VHRS (P < 0.01) and ACS-NSQIP (P < 0.05) stratified for SSI. In both databases, VHRS, VHWG, and Centers for Disease Control and Prevention overestimated risk of SSO and SSI, whereas HW-RAT and ACS-NSQIP underestimated risk for all groups.

CONCLUSIONS

All five existing predictive models have limited ability to risk-stratify patients and accurately assess risk of SSO. However, both the VHRS and ACS-NSQIP demonstrate modest success in identifying patients at risk for SSI. Continued model refinement is needed to improve the two highest performing models (VHRS and ACS-NSQIP) along with investigation to determine whether modifications to perioperative management based on risk stratification can improve outcomes.

Cost of ventral hernia repair using biologic or synthetic mesh

BACKGROUND

Patients undergoing ventral hernia repair (VHR) with biologic mesh (BioM) have higher hospital costs compared with synthetic mesh (SynM). This study compares 90-d pre- and post-VHR hospital costs (180-d) among BioM and SynM based on infection risk.

METHODS

This retrospective National Surgical Quality Improvement Program study matched patient perioperative risk with resource utilization cost for a consecutive series of VHR repairs. Patient infection risks, clinical and financial outcomes were compared in unmatched SynM (n = 303) and BioM (n = 72) groups. Propensity scores were used to match 35 SynM and BioM pairs of cases with similar infection risk for outcomes analysis.

RESULTS

BioM patients in the unmatched group were older with higher American Society of Anesthesiologists (ASA) and wound classification, and they more frequently underwent open repairs for recurrent hernias. Wound surgical site infections were more frequent in unmatched BioM patients (P = 0.001) as were 180-d costs ($43.8k versus $14.0k, P < 0.001). Propensity matching resulted in 31 clean cases. In these low-risk patients, wound occurrences and readmissions were identical, but 180-d costs remained higher ($31.8k versus $15.5k, P < 0.001). There were no differences in hospital 180-d diagnostic, emergency room, intensive care unit, floor, pharmacy, or therapeutic costs. However, 180-d operating room services and supply costs were higher in the BioM group ($21.1k versus $7.1k, P < 0.001).

CONCLUSIONS

BioM is used more commonly in hernia repairs involving higher wound class and ASA scores and recurrent hernias. Clinical outcomes after low-risk VHRs are similar; SynM utilization in low-risk hernia repairs was more cost-effective.