A 32-year-old man is brought to the emergency department following a high-speed motor vehicle collision. On primary survey, he is alert and oriented, with a patent airway and normal breathing. Pulse is 118/min, BP 94/60 mmHg, and capillary refill is 3 seconds. Abdominal examination reveals tenderness in the left upper quadrant with guarding. What is the most appropriate immediate next step in management?

Explanation

## Clinical Context This patient presents with signs of hemorrhagic shock (tachycardia, hypotension, delayed capillary refill) and a mechanism suggesting intra-abdominal injury (high-speed MVC with left upper quadrant tenderness and guarding). ## Primary Survey Assessment **Key Point:** The primary survey (ABCDE) has been completed — airway patent, breathing adequate, circulation compromised (Class II hemorrhagic shock). The patient is now in the secondary survey phase. ## FAST Examination Rationale **High-Yield:** FAST is the gold standard rapid imaging modality in ATLS protocol for detecting free fluid (blood) in the peritoneal cavity in trauma patients. It is: - Non-invasive and can be performed at the bedside - Rapid (takes 2–3 minutes) - Highly sensitive for detecting hemoperitoneum - Does not delay resuscitation - Guides decision for operative intervention **Clinical Pearl:** A positive FAST in a hemodynamically unstable patient with abdominal trauma is an indication for immediate operative exploration — no further imaging is needed. ## Sequence in ATLS 1. Complete primary survey (ABCDE) 2. Initiate resuscitation (IV access, fluid/blood) 3. Perform secondary survey with FAST for blunt abdominal trauma 4. Decide operative vs. non-operative management based on FAST + hemodynamic response **Mnemonic:** **FAST** = Focused Assessment with Sonography for Trauma. Evaluates four views: - **F**ree fluid in Morrison's pouch (RUQ) - **A**bdominal free fluid in pelvis - **S**plenorenal view (LUQ) - **T**horax (pericardial view for hemopericardium)