A 68-year-old man with a history of hypertension and smoking presents to the emergency department with sudden-onset severe back pain and hypotension (BP 85/50 mmHg). On examination, he is diaphoretic and in severe distress. A bedside ultrasound shows a large abdominal aortic aneurysm (AAA) with free fluid in the pelvis. What is the most appropriate immediate next step in management?

Explanation

## Management of Ruptured AAA **Key Point:** In a haemodynamically unstable patient with clinical and ultrasound evidence of ruptured AAA, immediate surgical intervention is the standard of care. Delay for further imaging is contraindicated and increases mortality. ### Rationale for Correct Answer This patient meets the diagnostic criteria for ruptured AAA: - Sudden severe back/abdominal pain - Hypotension (shock) - Pulsatile abdominal mass or imaging evidence of AAA - Free fluid on ultrasound **High-Yield:** In unstable patients with suspected rupture, bedside ultrasound or FAST examination is sufficient to proceed to the operating room. Further imaging (CT) delays definitive treatment and increases mortality risk. ### Why Imaging Delays Are Harmful Each minute of delay in an unstable patient with rupture increases mortality. The "golden hour" principle applies: mortality rises sharply if operative intervention is delayed beyond 60 minutes from presentation. ```mermaid flowchart TD A[Suspected ruptured AAA]:::outcome --> B{Haemodynamically stable?}:::decision B -->|Yes| C[CT angiography for confirmation and planning]:::action B -->|No| D[Bedside ultrasound/FAST]:::action D --> E{AAA + free fluid confirmed?}:::decision E -->|Yes| F[Immediate transfer to OR for emergency repair]:::action E -->|No| G[Consider other diagnoses, then CT if stable]:::action F --> H[Resuscitation in OR, cross-match blood]:::action C --> I[Plan approach: open vs EVAR]:::action ``` **Clinical Pearl:** Permissive hypotension is the strategy in ruptured AAA — avoid aggressive fluid resuscitation before aortic cross-clamping, as this can dislodge thrombus and worsen bleeding. Resuscitation should occur in the OR under surgical control. ### Comparison: Stable vs Unstable AAA | Feature | Stable AAA | Ruptured/Unstable AAA | |---------|-----------|----------------------| | **Imaging** | CT angiography mandatory | Bedside ultrasound sufficient | | **Haemodynamics** | Normal or mild hypertension | Hypotension, shock | | **Fluid resuscitation** | Standard IV access | Permissive hypotension; avoid over-resuscitation | | **Timing to OR** | Elective planning | Emergent (< 60 min) | | **Operative approach** | Open or EVAR | Open repair (EVAR not suitable in acute rupture) | [cite:Harrison 21e Ch 297]