Certified Transport Registered Nurse Certification Practice Exam

Physiologically, what may result from altitude beyond 20,000 ft?

1. Loss of consciousness

2. Improved blood circulation

3. Decreased risk of hypoxia

4. Enhanced aerobic capacity

The correct answer is: Loss of consciousness

At altitudes beyond 20,000 feet, individuals are exposed to significantly lower atmospheric pressure and reduced levels of oxygen, which can lead to a condition known as hypoxia. As altitude increases, the availability of oxygen decreases, making it more challenging for the body to maintain adequate oxygen levels for normal physiological function. Loss of consciousness can occur due to acute mountain sickness or hypoxia, as the brain is highly sensitive to oxygen deprivation. When the brain does not receive enough oxygen, it can impair cognitive and motor functions, leading to confusion, disorientation, and eventually loss of consciousness if the condition progresses without intervention. In contrast, the other options refer to physiological effects that are unlikely or negative at such high altitudes. Improved blood circulation, decreased risk of hypoxia, and enhanced aerobic capacity are not typically outcomes of exposure to extreme altitudes; rather, these conditions can result in further health complications related to oxygen deprivation. Thus, the correct answer highlights the critical risks associated with high-altitude exposure.