Snapshot A 45-year-old man presents to the emergency department after a fight. He has 2 stab wounds in his abdomen. A FAST exam is negative for intra-abdominal fluid. A chest radiography shows free air under the diaphragm. He is immediately given 2 liters of crystalloid fluid, broad-spectrum antibiotics, and taken to the operating room for surgical exploration. Introduction Overview bowel perforation often occurs due to penetrating injury from trauma or iatrogenic causes Epidemiology Risk factors penetrating trauma > blunt abdominal trauma acute diverticulitis malignancy inflammatory bowel disease ischemic bowel ETIOLOGY Pathogenesis mechanism blunt abdominal trauma deceleration and acceleration injuries compressive injuries increased luminal pressure penetrating trauma direct tissue disruption Presentation Symptoms common symptoms location abdominal pain Physical exam inspection hypotension tachycardia shock bruising motion tenderness to palpation rebound tenderness provocative tests peritoneal signs guarding rigidity Imaging Chest or abdominal radiograph indications all patients findings free air sudden onset pain and free air = bowel perforation which is an emergency a normal finding post-operatively manage expectantly Abdominal CT indications hemodynamically stable patients findings intraperitoneal fluid bowel wall discontinuity extraluminal air extraluminal contrast Abdominal ultrasound FAST exam focused abdominal sonography for trauma indications at bedside for all trauma patients findings intra-abdominal free fluid Studies Serum labs leukocytosis anemia lactic acid may indicate ischemic bowel Differential Splenic laceration key distinguishing factor splenic bleeding or hematoma on imaging Treatment Medical resuscitation indications all patients broad-spectrum antibiotics indications all patients Surgical exploratory laparotomy indications hemodynamically unstable patients bowel perforation Complications Intra-abdominal abscess Sepsis