Emergency Medical Technician (EMT) Basic Certification Practice Exam

What is the primary cause of neurogenic shock?

1. Head trauma

2. Injury to the thoracic spine or above

3. Extreme blood loss

4. Obstruction of airways

The correct answer is: Injury to the thoracic spine or above

Neurogenic shock occurs primarily due to the loss of sympathetic nervous system tone, which can result from an injury to the spinal cord, particularly at the thoracic spine level or above. This type of shock is characterized by the inability of blood vessels to constrict, leading to widespread vasodilation, which subsequently results in decreased blood flow and blood pressure. Injuries at the thoracic spine or higher disrupt the neural pathways that control vascular resistance, causing the blood vessels to remain dilated. As a result, the body cannot maintain adequate blood pressure, resulting in inadequate perfusion to vital organs. This condition is distinct from other forms of shock, such as hypovolemic shock from extreme blood loss or obstructive shock from airway obstruction, as it specifically arises from neurological impairment rather than fluid loss or physical blockage in circulation. Thus, understanding the primary cause of neurogenic shock is critical for emergency medical technicians, as it helps in diagnosing the condition promptly and implementing appropriate interventions.