Exposure to a hyperbaric chamber can lead to which major CNS complication?

• A. Convulsions
• B. Hypoxia
• C. Hypercapnia
• D. Cardiac arrest

Answer: (A)

Exposure to high-pressure oxygen in a hyperbaric chamber can cause CNS oxygen toxicity. When the oxygen partial pressure gets very high, brain neurons become hyperexcitable, leading to convulsions or seizures—the major CNS complication associated with hyperbaric exposure. Hypoxia isn’t expected here because the environment provides abundant oxygen; hypercapnia can occur if ventilation is inadequate but isn’t the classic CNS event; cardiac arrest, while life-threatening, is not a CNS complication. So convulsions best represent the primary CNS risk in this setting.