Emergency Medical Technician (EMT) Basic Certification Practice Exam

What characterizes a flail chest?

1. Air trapped in the pleural lining

2. Leakage of blood into the pleural space

3. Two or more ribs broken loose in two places

4. Pressure build-up leading to difficulty breathing

The correct answer is: Two or more ribs broken loose in two places

A flail chest is characterized by the presence of two or more ribs that are fractured in two or more places, resulting in a segment of the chest wall that becomes detached from the rest of the thoracic cage. This condition significantly affects respiratory mechanics because the detached segment can move paradoxically, meaning it may sink in during inhalation and bulge out during exhalation, contrary to the normal movement of the chest wall. This abnormal motion can compromise respiratory function and lead to decreased oxygenation due to reduced lung expansion and potential underlying lung injury. Understanding this condition is crucial for EMTs and other healthcare providers since it necessitates prompt recognition and intervention to stabilize the patient, often involving addressing any underlying lung injuries and ensuring adequate ventilation. The other options do not accurately describe a flail chest; for instance, air trapped in the pleural lining refers to pneumothorax, while the leakage of blood into the pleural space describes hemothorax, both of which are distinct conditions not characterized by the structural problems of flail chest. Similarly, pressure build-up resulting in difficulty breathing can be associated with various thoracic emergencies but does not specifically pertain to the rib fractures that define a flail chest.