Certified Flight Registered Nurse (CFRN) Practice Exam (2)

The autonomic function that is not regulated by endogenous catecholamines is a decrease in the respiratory rate. Endogenous catecholamines, such as epinephrine and norepinephrine, primarily affect the sympathetic nervous system, which is responsible for the "fight or flight" response. When catecholamines are released, they increase the heart rate, increase blood pressure, and enhance respiratory rate through bronchial dilation to facilitate greater oxygen intake. These effects are crucial during times of stress or emergency, promoting heightened alertness and physical readiness. In contrast, a decrease in respiratory rate typically aligns with the activation of the parasympathetic nervous system, which is responsible for conserving energy and promoting a restful state. Thus, while catecholamines play a significant role in various autonomic functions related to stress responses, they do not contribute to a downward regulation of the respiratory rate.