Bradypnea can be caused by which of the following?

• A. Oversedation
• B. Hyperventilation
• C. Dehydration
• D. Anxiety

Answer: (A)

Bradypnea is a slower-than-normal breathing rate caused by reduced respiratory drive from the brainstem. Oversedation from sedatives, especially opioids, depresses the brain’s respiratory centers, lowering both the rate and the depth of breaths. In overdose or deep sedation, this can show up as bradypnea and can progress to hypoventilation or apnea, a dangerous sign. The other options don’t fit as well: hyperventilation speeds up breathing, not slows it; dehydration by itself doesn’t typically slow breathing and may even cause other metabolic changes; anxiety tends to increase respiratory rate due to sympathetic activation.