A 28-year-old woman is brought to the trauma centre 45 minutes after a stab wound to the right lower quadrant. On examination, she is haemodynamically stable (BP 124/78 mmHg, HR 88/min), with localized tenderness at the wound site but no peritoneal signs. FAST is negative for free fluid. CT abdomen with IV contrast shows a small laceration of the caecum with minimal surrounding free fluid, but no active extravasation. What is the most appropriate next step in management?

Explanation

## Management of Penetrating Abdominal Trauma (Stab Wound) with Organ Injury **Key Point:** Any penetrating abdominal injury with radiological evidence of solid organ or hollow viscus injury requires operative exploration, regardless of haemodynamic stability or absence of peritoneal signs at presentation. ### Why Operative Management is Mandatory 1. **Hollow Viscus Injury (Caecal Laceration)** - Caecal injury carries high risk of faecal contamination and peritonitis - Even small lacerations can lead to delayed sepsis if not repaired - Peritoneal signs may be absent initially but develop over hours - Risk of undetected associated injuries (mesentery, vessels, adjacent bowel) 2. **Difference Between Blunt and Penetrating Trauma** - **Blunt trauma:** Haemodynamic stability + negative imaging = observation acceptable - **Penetrating trauma:** Imaging evidence of organ injury = mandatory exploration, even if stable - Penetrating injuries have unpredictable tract and multiple potential injuries not visible on imaging 3. **Rationale for Exploration Despite Stability** - CT may miss small mesenteric tears, vascular injuries, or diaphragmatic penetration - Faecal contamination from caecal injury can lead to fulminant peritonitis within 12–24 hours - Early operative repair prevents sepsis and reduces morbidity ### Management Algorithm for Penetrating Abdominal Trauma ```mermaid flowchart TD A[Penetrating abdominal wound]:::outcome --> B{Haemodynamically unstable or peritoneal signs?}:::decision B -->|Yes| C[Immediate exploratory laparotomy]:::action B -->|No| D{Imaging shows organ injury?}:::decision D -->|Yes - solid organ| E[Selective NOM if stable, ICU monitoring]:::action D -->|Yes - hollow viscus| F[Mandatory exploratory laparotomy]:::action D -->|No injury on imaging| G[Observe with serial exam, consider repeat imaging]:::action ``` **Clinical Pearl:** The classic teaching is that all penetrating abdominal injuries with evidence of organ injury on imaging require exploration. The exception is selective non-operative management of solid organ injuries (liver, kidney, spleen) in haemodynamically stable patients — but hollow viscus injuries (bowel, stomach, caecum) always require repair. **High-Yield:** Caecal injuries are particularly dangerous because: - High bacterial load in caecal contents - Rapid progression to peritonitis if not repaired - Risk of anastomotic leak if repair is delayed **Mnemonic: OPSI** — Overwhelming Post-Splenectomy Infection. While this refers to splenectomy, it underscores why preserving organ function and preventing contamination is critical in trauma. [cite:ATLS 10th Edition, Chapter 8: Abdominal Trauma; Sabiston Textbook of Surgery, Chapter 19: Trauma]