Cancer Survivorship: Defining the Incidence of Incisional Hernia After Resection for Intra-Abdominal Malignancy.

BACKGROUND: Cancer survivorship focuses largely on improving quality of life. We aimed to determine the rate of ventral incisional hernia (VIH) formation after cancer resection, with implications for survivorship. METHODS: Patients without prior VIH who underwent abdominal malignancy resections at a tertiary center were followed up to 2 years. Patients with a viewable preoperative computed tomography (CT) scan and CT within 2 years postoperatively were included. Primary outcome was postoperative VIH on CT, reviewed by a panel of surgeons uninvolved with the original operation. Factors associated with VIH were determined using Cox proportional hazards regression. RESULTS: 1847 CTs were reviewed among 491 patients (59 % men), with inter-rater reliability 0.85 for the panel. Mean age was 60 ± 12 years; mean follow-up time 13 ± 8 months. VIH occurred in 41 % and differed across diagnoses: urologic/gynecologic (30 %), colorectal (53 %), and all others (56 %) (p < 0.001). Factors associated with VIH (adjusting for stage, age, adjuvant therapy, smoking, and steroid use) included: incision location [flank (ref), midline, hazard ratio (HR) 6.89 (95 %CI 2.43-19.57); periumbilical, HR 6.24 (95 %CI 1.84-21.22); subcostal, HR 4.55 (95 %CI 1.51-13.70)], cancer type [urologic/gynecologic (ref), other {gastrointestinal, pancreatic, hepatobiliary, retroperitoneal, and others} HR 1.86 (95 %CI 1.26-2.73)], laparoscopic-assisted operation [laparoscopic (ref), HR 2.68 (95 %CI 1.44-4.98)], surgical site infection [HR 1.60 (95 %CI 1.08-2.37)], and body mass index [HR 1.06 (95 %CI 1.03-1.08)]. CONCLUSIONS: The rate of VIH after abdominal cancer operations is high. VIH may impact cancer survivorship with pain and need for additional operations. Further studies assessing the impact on QOL and prevention efforts are needed.

Patient reported outcomes after incisional hernia repair-establishing the ventral hernia recurrence inventory.

BACKGROUND: Assessing incisional hernia recurrence typically requires a clinical encounter. We sought to determine if patient-reported outcomes (PROs) could detect long-term recurrence. METHODS: Adult patients 1 to 5 years after incisional hernia repair were prospectively asked about recurrence, bulge, and pain at the original repair site. Using dynamic abdominal sonography for hernia to detect recurrence, performance of each PRO was determined. Multivariable regression was used to evaluate PRO association with recurrence. RESULTS: Fifty-two patients enrolled with follow-up time 46 ± 13 months. A patient-reported bulge was 85% sensitive, and 81% specific to detect recurrence. Patients reporting no bulge and no pain had 0% chance of recurrence. In multivariable analysis, patients reporting a bulge were 18 times more likely to have a recurrence than those without (95% confidence interval, 3.7 to 90.0; P < .001). CONCLUSIONS: This preliminary study demonstrates that PROs offer a promising means of detecting long-term recurrence after incisional hernia repair, which can help facilitate quality improvement and research efforts.

Incisional Hernia Classification Predicts Wound Complications Two Years after Repair.

Classification of ventral hernias (VHs) into categories that impact surgical outcome is not well defined. The European Hernia Society (EHS) classification divides ventral incisional hernias by midline or lateral location. This study aimed to determine whether EHS classification is associated with wound complications after VH repair, indicated by surgical site occurrences (SSOs). A retrospective cohort study of patients who underwent VH repair at a tertiary referral center between July 1, 2005 and May 30, 2012, was performed. EHS classification, comorbidities, and operative details were determined. Primary outcome was SSO within two years, defined as an infection, wound dehiscence, seroma, or enterocutaneous fistula. There were 538 patients included, and 51.5 per cent were female, with a mean age of 54.2 ± 12.4 years and a mean body mass index of 32.4 ± 8.6 kg/m(2). Most patients had midline hernias (87.0%, n = 468). There were 47 patients (8.7%) who had a lateral hernia, and 23 patients (4.3%) whose repair included both midline and lateral components. Overall rate of SSO was 39 per cent (n = 211) within two years. The rate of SSO by VH location was: 39 per cent (n = 183) for midline, 23 per cent (n = 11) for lateral, and 74 per cent (n = 17) for VHs with midline and lateral components (P = <0.001). Patients whose midline hernia spanned more than one EHS category also had a higher rate of SSOs (P = 0.001). VHs are often described by transverse dimension alone, but a more descriptive classification system offers a richness that correlates with outcomes.

Previous Methicillin-Resistant Staphylococcus aureus Infection Independent of Body Site Increases Odds of Surgical Site Infection after Ventral Hernia Repair.

BACKGROUND: Methicillin-resistant Staphylococcus aureus infections can be difficult to manage in ventral hernia repair (VHR). We aimed to determine whether a history of preoperative MRSA infection, regardless of site, confers increased odds of 30-day surgical site infection (SSI) after VHR. STUDY DESIGN: A retrospective cohort study of patients undergoing VHR with class I to III wounds between 2005 and 2012 was performed using Vanderbilt University Medical Center's Perioperative Data Warehouse. Preoperative MRSA status, site of infection, and 30-day SSI were determined. Univariate and multivariate analyses adjusting for confounding factors were performed to determine whether a history of MRSA infection was independently associated with SSIs. RESULTS: A total of 768 VHR patients met inclusion criteria, of which 46% were women. There were 54 (7%) preoperative MRSA infections (MRSA positive); 15 (28%) soft tissue, 9 (17%) bloodstream, 4 (7%) pulmonary, 3 (6%) urinary, and 5 (9%) other. Overall SSI rate was 10% (n = 80), SSI rate in the MRSA-positive group was 33% (n = 18), compared with 9% (n = 62) in controls (p < 0.001). Multivariate analysis demonstrated that a history of MRSA infection significantly increased odds of 30-day SSI after VHR by 2.3 times (95% CI, 1.1-4.8; p = 0.035). Other factors associated with postoperative SSI were performance of myofascial release, increasing BMI, length of operation, open repair, and clean-contaminated wound classification. CONCLUSIONS: A history of site-independent MRSA infection confers significantly increased odds of 30-day SSI after VHR. Additional investigation is needed to determine perioperative treatment regimens that might decrease odds of SSI in VHR, and optimal prosthetic types and techniques for this population.

Remodeling characteristics and collagen distribution in biological scaffold materials explanted from human subjects after abdominal soft tissue reconstruction: an analysis of scaffold remodeling characteristics by patient risk factors and surgical site classifications.

OBJECTIVE: The study purpose was to evaluate the associations between patient characteristics or surgical site classifications and the histologic remodeling scores of biologic meshes biopsied from abdominal soft tissue repair sites in the first attempt to generate a multivariable risk-prediction model of nonconstructive remodeling. BACKGROUND: Host characteristics and surgical site assessments may predict remodeling degree for biologic meshes used to reinforce abdominal tissue repair sites. METHODS: Biologic meshes were biopsied from the abdominal tissue repair sites of n = 40 patients during an abdominal reexploration, stained with hematoxylin and eosin, and evaluated according to a semi-quantitative scoring system for remodeling characteristics (cell types, cell infiltration, extracellular matrix deposition, scaffold degradation, fibrous encapsulation, and neovascularization) and a mean composite score. Biopsies were stained with Sirius Red and Fast Green and analyzed to determine the collagen I:III ratio. On the basis of univariate analyses between subject clinical characteristics or surgical site classification and the histologic remodeling scores, cohort variables were selected for multivariable regression models using P ≤ 0.200. RESULTS: The model selection process for cell infiltration score yielded 2 variables: age at mesh implantation and mesh classification (C statistic = 0.989). For the mean composite score, the model selection process yielded 2 variables: age at mesh implantation and mesh classification (r = 0.449). CONCLUSIONS: These preliminary results constitute the first steps in generating a risk-prediction model that predicts the patients and clinical circumstances most likely to experience nonconstructive remodeling of abdominal tissue repair sites with biologic mesh reinforcement.

FLS tasks can be used as an ergonomic discriminator between laparoscopic and robotic surgery.

INTRODUCTION: Robotic surgery may result in ergonomic benefits to surgeons. In this pilot study, we utilize surface electromyography (sEMG) to describe a method for identifying ergonomic differences between laparoscopic and robotic platforms using validated Fundamentals of Laparoscopic Surgery (FLS) tasks. We hypothesize that FLS task performance on laparoscopic and robotic surgical platforms will produce significant differences in mean muscle activation, as quantified by sEMG. METHODS: Six right-hand-dominant subjects with varying experience performed FLS peg transfer (PT), pattern cutting (PC), and intracorporeal suturing (IS) tasks on laparoscopic and robotic platforms. sEMG measurements were obtained from each subject's bilateral bicep, tricep, deltoid, and trapezius muscles. EMG measurements were normalized to the maximum voluntary contraction (MVC) of each muscle of each subject. Subjects repeated each task three times per platform, and mean values used for pooled analysis. Average normalized muscle activation (%MVC) was calculated for each muscle group in all subjects for each FLS task. We compared mean %MVC values with paired t tests and considered differences with a p value less than 0.05 to be statistically significant. RESULTS: Mean activation of right bicep (2.7 %MVC lap, 1.3 %MVC robotic, p = 0.019) and right deltoid muscles (2.4 %MVC lap, 1.0 %MVC robotic, p = 0.019) were significantly elevated during the laparoscopic compared to the robotic IS task. The mean activation of the right trapezius muscle was significantly elevated during robotic compared to the laparoscopic PT (1.6 %MVC lap, 3.5 %MVC robotic, p = 0.040) and PC (1.3 %MVC lap, 3.6 %MVC robotic, p = 0.0018) tasks. CONCLUSIONS: FLS tasks are validated, readily available instruments that are feasible for use in demonstrating ergonomic differences between surgical platforms. In this study, we used FLS tasks to compare mean muscle activation of four muscle groups during laparoscopic and robotic task performance. FLS tasks can serve as the basis for larger studies to further describe ergonomic differences between laparoscopic and robotic surgery.

Remodeling characteristics and collagen distribution in synthetic mesh materials explanted from human subjects after abdominal wall reconstruction: an analysis of remodeling characteristics by patient risk factors and surgical site classifications.

BACKGROUND: The purpose of this study was to evaluate the associations between patient characteristics or surgical site classifications and the histologic remodeling scores of synthetic meshes biopsied from their abdominal wall repair sites in the first attempt to generate a multivariable risk prediction model of non-constructive remodeling. METHODS: Biopsies of the synthetic meshes were obtained from the abdominal wall repair sites of 51 patients during a subsequent abdominal re-exploration. Biopsies were stained with hematoxylin and eosin, and evaluated according to a semi-quantitative scoring system for remodeling characteristics (cell infiltration, cell types, extracellular matrix deposition, inflammation, fibrous encapsulation, and neovascularization) and a mean composite score (CR). Biopsies were also stained with Sirius Red and Fast Green, and analyzed to determine the collagen I:III ratio. Based on univariate analyses between subject clinical characteristics or surgical site classification and the histologic remodeling scores, cohort variables were selected for multivariable regression models using a threshold p value of ≤0.200. RESULTS: The model selection process for the extracellular matrix score yielded two variables: subject age at time of mesh implantation, and mesh classification (c-statistic = 0.842). For CR score, the model selection process yielded two variables: subject age at time of mesh implantation and mesh classification (r (2) = 0.464). The model selection process for the collagen III area yielded a model with two variables: subject body mass index at time of mesh explantation and pack-year history (r (2) = 0.244). CONCLUSION: Host characteristics and surgical site assessments may predict degree of remodeling for synthetic meshes used to reinforce abdominal wall repair sites. These preliminary results constitute the first steps in generating a risk prediction model that predicts the patients and clinical circumstances for which non-constructive remodeling of an abdominal wall repair site with synthetic mesh reinforcement is most likely to occur.

A material cost-minimization analysis for hernia repairs and minor procedures during a surgical mission in the Dominican Republic.

INTRODUCTION: Expenditures on material supplies and medications constitute the greatest per capita costs for surgical missions. We hypothesized that supply acquisition at non-profit organization (NPO) costs would lead to significant cost-savings compared with supply acquisition at US academic institution costs from the provider perspective for hernia repairs and minor procedures during a surgical mission in the Dominican Republic. METHODS: Items acquired for a surgical mission were uniquely QR-coded for accurate consumption accounting. Both NPO and US academic institution unit costs were associated with each item in an electronic inventory system. Medication doses were recorded and QR codes for consumed items were scanned into a record for each sampled procedure. Mean material costs and cost-savings ± SDs were calculated in US dollars for each procedure type. Cost-minimization analyses between the NPO and the US academic institution platforms for each procedure type ensued using a two-tailed Wilcoxon matched-pairs test with α = 0.05. Item utilization analyses generated lists of most frequently used materials by procedure type. RESULTS: The mean cost-savings of supply acquisition at NPO costs for each procedure type were as follows: $482.86 ± $683.79 for unilateral inguinal hernia repair (n = 13); $332.46 ± $184.09 for bilateral inguinal hernia repair (n = 3); $127.26 ± $13.18 for hydrocelectomy (n = 9); $232.92 ± $56.49 for femoral hernia repair (n = 3); $120.90 ± $30.51 for umbilical hernia repair (n = 8); $36.59 ± $17.76 for minor procedures (n = 26); and $120.66 ± $14.61 for pediatric inguinal hernia repair (n = 7). CONCLUSION: Supply acquisition at NPO costs leads to significant cost-savings compared with supply acquisition at US academic institution costs from the provider perspective for inguinal hernia repair, hydrocelectomy, umbilical hernia repair, minor procedures, and pediatric inguinal hernia repair during a surgical mission in the Dominican Republic. Item utilization analysis can generate minimum-necessary material lists for each procedure type to reproduce cost-savings for subsequent missions.