True or false: Oxygen toxicity can accompany confusion.

• A. True
• B. False
• C. Not enough data
• D. Sometimes

Answer: (A)

Oxygen toxicity can accompany confusion because oxygen reaching the brain at high partial pressures can disrupt neural function. When the inspired oxygen partial pressure is elevated (as with deep dives using enriched air or rebreathers), CNS toxicity can occur, producing symptoms such as dizziness, vision changes, irritability, and confusion. Confusion is a recognized sign of CNS oxygen toxicity and can precede more serious events if exposure continues. So the statement is true. In practice, spotting confusion means reducing exposure to high-oxygen gas—ascend to shallower depth or switch to a gas with a lower oxygen fraction and follow appropriate safety steps.