Incidence and risk factors for parastomal hernia with a permanent colostomy

Repair of Parastomal Hernias

Parastomal hernias are an inevitable consequence of ostomy formation and their repairs remain a challenge to many surgeons. With multiple systems of classification and a multitude of techniques for hernia repair ranging from suture to mesh repair, the literature remains sparse with regards to the optimal method of repair. The authors describe the most commonly adopted techniques, discuss preventative measures, and review the current literature in the context of perioperative outcomes and hernia recurrence.

A risk prediction model based on machine learning algorithm for parastomal hernia after permanent colostomy

OBJECTIVE

To develop a machine learning-based risk prediction model for postoperative parastomal hernia (PSH) in colorectal cancer patients undergoing permanent colostomy, assisting nurses in identifying high-risk groups and devising preventive care strategies.

METHODS

A case-control study was conducted on 495 colorectal cancer patients who underwent permanent colostomy at the Second Affiliated Hospital of Anhui Medical University from June 2017 to June 2023, with a 1-year follow-up period. Patients were categorized into PSH and non-PSH groups based on PSH occurrence within 1-year post-operation. Data were split into training (70%) and testing (30%) sets. Variable selection was performed using Least Absolute Shrinkage and Selection Operator (LASSO) regression, and binary classification prediction models were established using Logistic Regression (LR), Support Vector Classification (SVC), K Nearest Neighbor (KNN), Random Forest (RF), Light Gradient Boosting Machine (LGBM), and Extreme Gradient Boosting (XgBoost). The binary classification label denoted 1 for PSH occurrence and 0 for no PSH occurrence. Parameters were optimized via 5-fold cross-validation. Model performance was evaluated using Area Under Curve (AUC), specificity, sensitivity, accuracy, positive predictive value, negative predictive value, and F1-score. Clinical utility was evaluated using decision curve analysis (DCA), model explanation was enhanced using shapley additive explanation (SHAP), and model visualization was achieved using a nomogram.

RESULTS

The incidence of PSH within 1 year was 29.1% (144 patients). Among the models tested, the RF model demonstrated the highest discrimination capability with an AUC of 0.888 (95% CI: 0.881-0.935), along with superior specificity, accuracy, sensitivity, and F1 score. It also showed the highest clinical net benefit on the DCA curve. SHAP analysis identified the top 10 influential variables associated with PSH risk: body mass index (BMI), operation duration, history and status of chronic obstructive pulmonary disease (COPD), prealbumin, tumor node metastasis (TNM) staging, stoma site, thickness of rectus abdominis muscle (TRAM), C-reactive protein CRP, american society of anesthesiologists physical status classification (ASA), and stoma diameter. These insights from SHAP plots illustrated how these factors influence individual PSH outcomes. The nomogram was used for model visualization.

CONCLUSION

The Random Forest model demonstrated robust predictive performance and clinical relevance in forecasting colonic PSH. This model aids in early identification of high-risk patients and guides preventive care.

Proof of concept of an experimental prototype for the prevention of parastomal hernia

PURPOSE

The aim of this study was to analyse the complications and problems associated with the use of an experimental prototype designed for the prevention of parastomal hernia (PSH), one of the most frequent complications in ostomates.

METHODS

A single-centre, non-comparative, proof-of-concept interventional pilot study of an experimental prototype designed to be used in conjunction with an abdominal compression binder to prevent PSH was conducted. The "Ostomy Fixation Device for Hernia Prevention" (patent P201531826) is a semi-rigid ostomy protector, to be used in conjunction with a compression binder. It is designed to adapt to the dimensions of standard ostomy bags from different brands and serves to transmit, in a localised manner, the support coming from the compression binder in the peristomal area without putting pressure on the collection bag. The main outcome measures were efficacy, safety, and patient-users' opinion/perception.

RESULTS

Ten patients were studied for 12 months. Mean age was 61 years (± 11.59), 70% (7) were male, 80% (8) ostomised for colorectal cancer, 90% (9) underwent planned surgery and 80% (8) had a colostomy.

EFFICACY

the incidence of HPE was 10% (1).

SAFETY

no participant experienced pain, discomfort, itching, stinging, leakage, pouch detachment, allergy to components, or injury to the stoma or peristomal skin due to rubbing or pressure. 90% (n = 9) were considered "very satisfied" or "satisfied" with the device.

CONCLUSIONS

An innovative device designed in collaboration between healthcare professionals and end-users has been shown to be safe and effective in reducing PSH in the group of ostomates studied.

Parastomal Hernia Repair

Parastomal hernias (PHs) are common and contribute to significant patient morbidity. Despite 45 years of evolution, mesh-based PH repairs continue to be challenging to perform and remain associated with high rates of postoperative complications and recurrences. In this article, the authors summarize the critical factors to consider when evaluating a patient for PH repair. The authors provide an overview of the current techniques for repair, including both open and minimally invasive approaches. The authors detail the mesh-based repair options and review the evidence for choice of mesh to use for repair.