Differential risk factors for intestinal ischemia and intestinal necrosis in acute irreducible groin hernia: development and internal validation of a two-stage risk stratification model

Acute irreducible groin hernia requires timely management, but the extent of bowel compromise and the likelihood of intestinal resection are often difficult to anticipate before surgery. Intestinal ischemia and irreversible necrosis represent distinct stages of bowel injury and may be associated with different clinical, inflammatory, and anatomical factors. This study investigated stage-specific risk factors and developed two corresponding preoperative risk models. We retrospectively analyzed 224 consecutive adults undergoing emergency surgery for acute irreducible groin hernia (2016–2025). An ischemia prediction model was developed by comparing patients with intestinal ischemia ( n = 100) and non-ischemia ( n = 124). A second multivariable model was subsequently developed within the ischemia subgroup by comparing patients with reversible intestinal ischemia ( n = 45) and those with intestinal necrosis ( n = 55). Models were evaluated by area under the curve (AUC), calibration, and decision curve analysis, with internal validation by bootstrapping (1000 resamples). For the full cohort, independent predictors for intestinal ischemia included symptom duration (OR 1.04, 95% CI 1.01–1.07), cardiovascular disease (OR 5.18, 1.42–18.83), bowel obstruction (OR 9.48, 3.90–23.04), a smaller hernia sac neck diameter (OR 0.85, 0.79–0.92), and an elevated neutrophil-to-lymphocyte ratio (NLR; OR 1.11, 1.04–1.18). The ischemia model demonstrated strong performance with an AUC of 0.906 (0.866–0.946), a Hosmer-Lemeshow P-value of 0.813, and a bootstrap-corrected C-statistic of 0.895. Hypertension (OR 5.06, 1.22–20.91), hernia sac fluid (OR 17.23, 4.67–63.56), and NLR (OR 1.13, 1.01–1.25) were independently associated with intestinal necrosis within the ischemia subgroup. Decision curve analysis showed potential net benefit across the evaluated threshold probabilities. Intestinal ischemia and its progression to necrosis were associated with different preoperative risk profiles. The two models provide stage-specific preoperative estimates of bowel compromise and may offer a structured framework for preoperative counseling and anticipation of intestinal resection. Their potential role in perioperative planning requires prospective multicenter validation before clinical implementation.