Predictors of Ischemic Bowel in Patients with Small Bowel Obstruction

Preoperative diagnosis of ischemic bowel in patients with small bowel obstruction (SBO) is a clinical challenge. The aim of this study was to identify preoperative variables associated with ischemic bowel found at operative exploration. We performed a 5-year retrospective review of patients admitted to a university affiliated, county funded hospital who underwent exploratory laparoscopy or laparotomy for SBO. Patients were excluded if they had a known preoperative malignancy or hernia on physical examination. Multivariate logistic regression was used to determine factors independently associated with bowel ischemia or ischemic perforation. One hundred and sixteen patients underwent exploratory surgery for SBO. Mean age was 52 ± 14 years and most were male [64 (55.2%)]. Adhesions [92 (79.3%)] were the most common etiology of obstruction. Leukocytosis (P = 0.304) and acidosis (P = 0.151) were not significantly associated with ischemia or ischemic perforation. In addition, history of prior SBO (P = 0.618), tachycardia (P = 0.111), fever (P = 0.859), and time from admission to operation (P = 0.383) were not predictive of ischemic bowel. However, hyponatremia (≤134 mmol/L) and CT scan findings of wall thickening or a suspected closed loop were independently associated with bowel ischemia. Awareness of these predictors should heighten the concern for ischemic bowel in patients presenting with SBO.