Predictors of ischemic bowel in patients with incarcerated hernias.

PURPOSE: Diagnosing intestinal strangulation in the setting of incarcerated hernias remains challenging. Hyponatremia has been identified as a predictor of necrotizing soft tissue infections and gangrenous cholecystitis. We hypothesized that hyponatremia could predict bowel ischemia in patients with incarcerated hernias.

METHODS: Medical records for 163 patients with incarcerated hernias over a 5-year period were reviewed. Preoperative clinical, laboratory, and radiologic findings and final intraoperative diagnosis were collected.

RESULTS: Thirty-six patients (22.1%) had ischemic bowel requiring resection. Univariate analysis identified multiple significant variables including lower serum sodium (p = 0.002), lower bicarbonate (p = 0.04), elevated glucose (p = 0.0002), elevated white blood cell count (p = 0.001), and skin changes (p = 0.001). In a multivariable model, skin changes were associated with an odds ratio for ischemia of 3.3 (1.3-8.6 p = 0.02). Sodium of less than 135 had an odds ratio for ischemia of 3.9 (1.7-9.1, p = 0.004).

CONCLUSION: Hyponatremia should raise suspicion for underlying strangulated bowel and prompt urgent exploration in patients with incarcerated hernias.