New York State Basic Emergency Medical Technician (EMT-B) Practice Exam

Complete airway obstruction can result in:

1. Increased heart rate

2. Loss of consciousness

3. Shortness of breath

4. Cyanosis

The correct answer is: Loss of consciousness

Complete airway obstruction leads to a significant reduction or cessation of airflow to the lungs. This situation prevents the body from obtaining oxygen, which is critical for sustaining life and maintaining normal physiological functions. As oxygen levels decrease, the body cannot function properly, leading to a state of hypoxia. The brain is especially sensitive to low oxygen levels, and when oxygen supply is insufficient for a prolonged period, it can result in a loss of consciousness. This is often a protective response from the body, as the brain prioritizes its need for oxygen, and by losing consciousness, it may reduce the body's metabolic demands temporarily. While other options like increased heart rate, shortness of breath, and cyanosis may occur as a response to airway obstruction, they do not signify the immediate and life-threatening consequence of airway blockage as effectively as the possibility of loss of consciousness does. Loss of consciousness signals a critical level of oxygen deprivation affecting the brain, making it a fundamental outcome of complete airway obstruction.