The enigma of incisional hernia prediction unraveled: external validation of a prognostic model in colorectal cancer patients.

PURPOSE: Accurate prediction of hernia occurrence is vital for surgical decision-making and patient management, particularly in colorectal surgery patients. While a hernia prediction model has been developed, its performance in external populations remain to be investigated. This study aims to validate the existing model on an external dataset of patients who underwent colorectal surgery. METHODS: The "Penn Hernia Calculator" model was externally validated using the Hughes Abdominal Repair Trial (HART) data, a randomized trial comparing colorectal cancer surgery closure techniques. The data encompassed demographics, comorbidities, and surgical specifics. Patients without complete follow-up were omitted. Model performance was assessed using key metrics, including area under the curve (AUC-ROC and AUC-PR) and Brier score. Reporting followed the TRIPOD consensus. RESULTS: An external international dataset consisting of 802 colorectal surgery patients were identified, of which 674 patients with up to 2 years follow-up were included. Average patient age was 68 years, with 63.8% male. The average BMI was 28.1. Prevalence of diabetes, hypertension, and smoking were 15.7%, 16.3%, and 36.5%, respectively. Additionally, 7.9% of patients had a previous hernia. The most common operation types were low anterior resection (35.3%) and right hemicolectomy (34.4%). Hernia were observed in 24% of cases by 2-year follow-up. The external validation model revealed an AUC-ROC of 0.66, AUC-PR of 0.72, and a Brier score of 0.2. CONCLUSION: The hernia prediction model demonstrated moderate performance in the external validation. Its potential generalizability, specifically in those undergoing colorectal surgery, may suggest utility in identifying and managing high-risk hernia candidates.

Optimal computed tomography-based biomarkers for prediction of incisional hernia formation.

PURPOSE: Unstructured data are an untapped source for surgical prediction. Modern image analysis and machine learning (ML) can harness unstructured data in medical imaging. Incisional hernia (IH) is a pervasive surgical disease, well-suited for prediction using image analysis. Our objective was to identify optimal biomarkers (OBMs) from preoperative abdominopelvic computed tomography (CT) imaging which are most predictive of IH development. METHODS: Two hundred and twelve rigorously matched colorectal surgery patients at our institution were included. Preoperative abdominopelvic CT scans were segmented to derive linear, volumetric, intensity-based, and textural features. These features were analyzed to find a small subset of OBMs, which are maximally predictive of IH. Three ML classifiers (Ensemble Boosting, Random Forest, SVM) trained on these OBMs were used for prediction of IH. RESULTS: Altogether, 279 features were extracted from each CT scan. The most predictive OBMs found were: (1) abdominopelvic visceral adipose tissue (VAT) volume, normalized for height; (2) abdominopelvic skeletal muscle tissue volume, normalized for height; and (3) pelvic VAT volume to pelvic outer aspect of body wall skeletal musculature (OAM) volume ratio. Among ML prediction models, Ensemble Boosting produced the best performance with an AUC of 0.85, accuracy of 0.83, sensitivity of 0.86, and specificity of 0.81. CONCLUSION: These OBMs suggest increased intra-abdominopelvic volume/pressure as the salient pathophysiologic driver and likely mechanism for IH formation. ML models using these OBMs are highly predictive for IH development. The next generation of surgical prediction will maximize the utility of unstructured data using advanced image analysis and ML.

National epidemiologic trends (2008-2018) in the United States for the incidence and expenditures associated with incisional hernia in relation to abdominal surgery.

PURPOSE: It is unknown whether the trend of rising incisional hernia (IH) repair (IHR) incidence and costs until 2011 currently persists. We aimed to evaluate how the IHR procedure incidence, cost and patient risk-profile have changed over the last decade relative to all abdominal surgeries (AS). METHODS: Repeated cross-sectional analysis of 38,512,737 patients undergoing inpatient 4AS including IHR within the 2008-2018 National Inpatient Sample. Yearly incidence (procedures/1,000,000 people [PMP]), hospital costs, surgical and patient characteristics were compared between IHR and AS using generalized linear and multinomial regression. RESULTS: Between 2008-2018, 3.1% of AS were IHR (1,200,568/38,512,737). There was a steeper decrease in the incidence of AS (356.5 PMP/year) compared to IHR procedures (12.0 PMP/year) which resulted in the IHR burden relative to AS (2008-2018: 12,576.3 to 9,113.4 PMP; trend difference P < 0.01). National costs averaged $47.9 and 1.7 billion/year for AS and IHR, respectively. From 2008-2018, procedure costs increased significantly for AS (68.2%) and IHR (74.6%; trends P < 0.01). Open IHR downtrended (42.2%), whereas laparoscopic (511.1%) and robotic (19,301%) uptrended significantly (trends P < 0.01). For both AS and IHR, the proportion of older (65-85y), Black and Hispanic, publicly-insured, and low-income patients, with higher comorbidity burden, undergoing elective procedures at small- and medium-sized hospitals uptrended significantly (all P < 0.01). CONCLUSION: IH persists as a healthcare burden as demonstrated by the increased proportion of IHR relative to all AS, disproportionate presence of high-risk patients that undergo these procedures, and increased costs. Targeted efforts for IH prevention have the potential of decreasing $17 M/year in costs for every 1% reduction.

The Abdominal Hernia-Q: a critical analysis of the components that impact quality-of-life.

PURPOSE: Ventral hernias (VH) are a common surgical problem associated with significant morbidity. While assessment tools have examined quality-of-life (QoL), the relative change in specific domains of hernia-related QoL measures from pre- to post-operative period has yet to be comprehensively examined. Using the Abdominal Hernia-Q (AHQ), this study aims to assess the impact of ventral hernia repair (VHR) on key components of QoL. METHODS: A retrospective chart review was conducted of patients undergoing VHR between September 2017 and September 2019 who had completed at least one pre- and post-operative AHQ. Post-operative intervals were created to capture AHQ responses around standard follow-up visits (< 1.5 months, 1.5-4.5 months, 4.5-11 months, and 11 + months) and scores were statistically analyzed. RESULTS: A total of 136 patients were included, with an average age of 54.8 years at the time of VHR. Compared to the pre-operative period, the appearance score increased significantly (p < 0.05). The physical domain score increased from < 1.5 month to the 1.5-4.5 month period (p = 0.03) and remained significantly higher in later time period. The appearance score decreased from the 1.5-4.5 month to 4.5-11 month period (p = 0.05). CONCLUSIONS: VHR leads to a sustained multi-dimensional increase in hernia-specific QoL measures during the post-operative course driven by early positive changes in appearance and sustained physical functioning. The initial increase in QoL is mainly driven by an improvement in appearance, while the sustained increase may be due to restored physical function.

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

PURPOSE: Despite continued efforts, recurrence after ventral hernia repair (VHR) remains a common problem. Biosynthetic Phasix™ (Poly-4-Hydroxybutyrate, P4HB) mesh combines the durability of synthetic mesh with the bio-resistance of biologics. P4HB has shown promising early outcomes, but long-term data are lacking. We examine patients following VHR with P4HB with at least 3 years of follow-up to assess clinical and patient reported outcomes (PROs). METHODS: Adult patients (≥ 18 years old) undergoing VHR with P4HB mesh between 10/2015 and 01/2018 by a single surgeon were retrospectively identified. Patients with < 36 months of follow-up were excluded unless they had a documented recurrence. Clinical outcomes and quality of life using the Hernia-Related Quality of Life Survey (HerQLes) were assessed. RESULTS: Seventy-one patients were included with a median age and body mass index of 61.2 and 31 kg/m2, respectively. Mesh was placed in the retromuscular (79%) and onlay (21%) planes with 1/3 of patients having hernias repaired in contaminated fields. There were no mesh infections, enterocutaneous fistulas, or mesh explantations. Nine patients (12.7%) developed recurrence at a median follow-up of 43.1 months [38.2-49.1]. Mesh plane, fixation technique, and Ventral Hernia Working Group were not associated with recurrence. Significant improvement in disease-specific PROs was observed and maintained at 3-year follow-up. CONCLUSION: Longitudinal clinical and quality of life outcomes after clean and contaminated VHR with P4HB are limited. Here, we conclude that P4HB is an effective and versatile mesh option for use in abdominal wall reinforcement.

The incisional hernia epidemic: evaluation of outcomes, recurrence, and expenses using the healthcare cost and utilization project (HCUP) datasets.

BACKGROUND: Incisional hernias (IH) following abdominal surgery persist as morbid, costly, and multi-disciplinary surgical challenges. Using longitudinal, multi-state, administrative claims data (HCUP State Inpatient Databases (SID)); (HCUP State Ambulatory Surgery and Services Databases (SASD)), we aimed to characterize the epidemiology, outcomes, recurrence, and costs of IH. STUDY DESIGN: 529,108 patients undergoing abdominal surgery in 2010 across six specialties (colorectal, general/bariatric, hepatobiliary, obstetrics/gynecology, urology, and vascular) were identified within inpatient and ambulatory databases for Florida (FL), Iowa (IA), Nebraska (NE), New York (NY), and Utah (UT). IH repairs, complications, and expenditures were assessed through 2014. Predictive regression modeling was validated using a training set of 1000 bootstrapped repetitions. RESULTS: 16,169 (3.1%) patients developed hernias requiring repair (4.3-year mean follow-up), 3176 (20%) underwent recurrent repair, and 731 (23%) underwent re-recurrent repair. Patients with IH had increased readmissions (6.6 vs. 2.4), morbidity (39 vs. 8% surgical and 22 vs. 7% medical), and costs ($46,000 vs. $25,000) when compared to patients without IH (p < 0.001). IH expenditures totaled $875 million: initial ($687 million), recurrent ($155 million), and re-recurrent hernias ($33 million). IH predominated in colorectal (10%), hepatobiliary (8%), and vascular (5%) procedures. Of 31 significant independent IH risk factors (p < 0.001), obesity, age, smoking, open surgery, and prior surgery were pervasive across surgical specialties. CONCLUSION: IH represents an unremitting surgical epidemic associated with considerable morbidity, costs, and features consistent with a chronic disease state. We define critical pervasive risk factors (obesity, age, smoking open surgery, and prior surgery) independently associated with IH across surgical disciplines. With failed repairs, subsequent success becomes less likely, increasing morbidity and costs-underscoring the critical importance of optimal treatment and prevention.

Ventral hernia repair with synthetic mesh in a contaminated field: a systematic review and meta-analysis.

PURPOSE: The use of mesh in ventral hernia repair becomes especially challenging when associated with a contaminated field. Permanent synthetic mesh use in this setting is currently debated and this discussion is yet to be resolved clinically or in the literature. We aim to systematically assess postoperative outcomes of non-absorbable synthetic mesh (NASM) used in ventral hernia repair in the setting of contamination. METHODS: A literature search of PubMed, Embase, Scopus, Cinahl, and Cochrane Library identified all articles from 2000-2020 that examined the use of NASM for ventral hernia repair in a contaminated field. Postoperative outcomes were assessed by means of pooled analysis and meta-analysis. Qualitative analysis was completed for all included studies using a modified Newcastle-Ottawa scale. RESULTS: Of 630 distinct publications and 104 requiring full review, this study included 17 articles published between 2007 and 2020. Meta-analysis demonstrated absorbable mesh was associated with more HR (OR 1.89, 1.15-3.12, p = 0.008), SSO (OR 1.43, 0.96-2.11, p = 0.087), SSI (OR 2.84, 1.85-4.35, p < 0.001), and unplanned reoperation (OR 1.99, 1.19-3.32, p = 0.009) compared to NASM. CONCLUSION: The use of NASM for ventral hernia repair in a contaminated field may be a safe alternative to absorbable mesh, as evidenced by lower rates of postoperative complications. This review counters the current clinical paradigm, and additional prospective randomized controlled trials are warranted.

Cutting through the fat: a retrospective analysis of clinical outcomes, cost, and quality of life with the addition of panniculectomy to ventral hernia repair in overweight patients.

BACKGROUND: Due to the increased prevalence of overweight patients with ventral hernia, abdominal wall reconstruction combining ventral hernia repair (VHR) with panniculectomy (VHR-PAN) in overweight patients is increasingly considered. We present a retrospective comparison between VHR-PAN and VHR alone in overweight patients by examining costs, clinical outcomes, and quality of life (QoL). METHODS: Patients with body mass index (BMI) > 25.0 kg/m2 underwent VHR-PAN or VHR alone between September 2015 and May 2017 with a single surgeon and were matched into cohorts by BMI and age (n = 24 in each cohort). QoL was assessed using the Hernia-related Quality of Life Survey (HerQLes). Cost was assessed using billing data. Statistical analyses were performed using Fisher's exact tests, Mann-Whitney U tests, and regression modeling. RESULTS: Hernia defect size (p = 0.127), operative time (p = 0.140), mesh placement (p = 0.357), and recurrence rates (p = 0.156) did not vary significantly between cohorts at average follow up of one year. 60% of patients completed QoL surveys, with 61% net improvement in VHR-PAN postoperatively (p = 0.042) vs 36% in VHR alone (p = 0.054). Mean total hospitalization costs were higher for VHR alone (p = 0.019). Regression modeling showed no significant independent contribution of procedure performed due to differences in cost, wound complications, or hernia recurrence. CONCLUSIONS: At mean follow up of 2 years, VHR-PAN patients reported a comparable increase in QoL to those who received VHR alone without significantly different cost and complication rates. Concurrent VHR-PAN may therefore be a safe approach for overweight patients presenting with hernia and excess abdominal skin.