TNCC Thoracic Trauma 2 — Questions and Answers
Question 1: Fractures of which ribs are associated with the greatest risk of great vessel injury and highest mortality?
- Ribs 1 and 2 (Correct answer)
- Ribs 4 through 8
- Ribs 9 through 12
- The sternum alone
Correct answer: Ribs 1 and 2
First and second rib fractures require tremendous force to break and are associated with injuries to great vessels, bronchi, and the brachial plexus, indicating extreme energy transfer.
Question 2: What is the primary pathophysiologic concern with pulmonary contusion?
- Pneumothorax from alveolar rupture
- Hemorrhage into lung parenchyma impairing gas exchange (Correct answer)
- Mediastinal shift from fluid accumulation
- Tracheal obstruction from blood clots
Correct answer: Hemorrhage into lung parenchyma impairing gas exchange
Pulmonary contusion causes hemorrhage and edema within lung parenchyma, reducing alveolar function and causing hypoxia that often worsens over the first 24-48 hours.
Question 3: Traumatic aortic disruption most commonly occurs at which anatomical location?
- Ascending aorta near the aortic valve
- Aortic arch at the brachiocephalic origin
- Aortic isthmus at the ligamentum arteriosum (Correct answer)
- Descending aorta at the diaphragmatic hiatus
Correct answer: Aortic isthmus at the ligamentum arteriosum
The aortic isthmus just distal to the left subclavian artery is the most common site of traumatic aortic injury because differential deceleration forces act at this transition between mobile and fixed aorta.
Question 4: Which chest tube output threshold most commonly indicates the need for surgical thoracotomy in hemothorax?
- More than 200 mL immediately on insertion
- More than 400 mL in the first hour
- 1,000-1,500 mL immediately or greater than 200 mL/hr ongoing (Correct answer)
- More than 500 mL over the first two hours
Correct answer: 1,000-1,500 mL immediately or greater than 200 mL/hr ongoing
Immediate drainage of 1,000-1,500 mL or ongoing output exceeding 200 mL/hr for 2-4 hours indicates active hemorrhage that the patient cannot self-tamponade and requires surgical control.
Question 5: Which assessment finding most reliably distinguishes tension pneumothorax from simple pneumothorax?
- Severity of respiratory distress and pain level
- Tracheal deviation and hemodynamic instability (Correct answer)
- Degree of hypoxia measured by pulse oximetry
- Presence or absence of subcutaneous emphysema
Correct answer: Tracheal deviation and hemodynamic instability
Tracheal deviation away from the affected side and hemodynamic instability (hypotension, shock) indicate mediastinal shift and obstructive shock, which are hallmarks of tension pneumothorax.
Question 6: A blunt trauma patient has decreased breath sounds on the right with the trachea in the midline and stable vital signs. What is the most likely diagnosis?
- Tension pneumothorax
- Massive hemothorax
- Simple pneumothorax or hemothorax (Correct answer)
- Cardiac tamponade
Correct answer: Simple pneumothorax or hemothorax
Midline trachea and stable hemodynamics rule out tension pneumothorax; decreased unilateral breath sounds without cardiovascular compromise suggest simple pneumothorax or hemothorax.
Question 7: At which intercostal space and location is chest tube thoracostomy typically inserted for trauma management?
- Second intercostal space, midclavicular line
- Fourth or fifth intercostal space, anterior axillary line (Correct answer)
- Third intercostal space, midaxillary line
- Sixth intercostal space, posterior axillary line
Correct answer: Fourth or fifth intercostal space, anterior axillary line
The fourth or fifth intercostal space at the anterior axillary line is the standard trauma chest tube site, positioned to drain both blood and air while avoiding abdominal organs.
TNCC Thoracic Trauma 2
Fractures of which ribs are associated with the greatest risk of great vessel injury and highest mortality?