**1.2. Breathing**

Auscultate for breathe sounds. Inspect for asymmetry of chest wall movement, open wounds, or flail segments. Palpate the chest wall carefully as palpable crepitus may indicate a pneumothorax or rib fractures. Pulse oximetry and capnography may be useful.

### **1.3. Circulation**

Stop gross external hemorrhage with direct pressure. Assess pulses, capillary refill, and blood pressure. Obtain intravenous access with at least two large bore (≥16 gauge) catheters. If peripheral intravenous access is inadequate, place a central venous catheter.

### **1.4. Disability**

Complete a brief and focused neurologic examination to document the patient's baseline. The examination should include an assessment of pupillary size and reactivity, a determination of the patient's Glasgow coma scale (GCS) score, and notation of any focal neurologic deficits such as unilateral weakness or poor muscle tone. Ideally, perform the examination before administering pain medications, sedatives, or paralytics.

### **1.5. Exposure**

Completely undress the patient, although be careful to prevent or recognize and correct associated hypothermia. Begin a more thorough secondary survey, including examining all skin folds, the back, and axillae for occult penetrating injuries.

Do not remove impaled foreign bodies because they may be providing hemostasis from a vascular injury. Foreign body removal should be performed with surgical consultation in a more controlled setting.

Any penetrating injury below the nipple line warrants evaluation for intra-abdominal injury. In patients in motor vehicle collisions, look for ecchymosis or erythema in the area of clavicles or across the abdomen. The classic "seat belt sign" or linear bruising across the lower abdomen is a marker for intra-abdominal injury.
