Which statement defines an open breathing system?

Which statement defines an open breathing system?

• A. A sealed system
• B. A breathing system that can entertain room air along with added oxygen
• C. A system that only uses pressurized gas
• D. A system that cannot entertain room air

Answer: (B)

Open breathing systems are defined by allowing ambient room air to mix with the gases delivered to the patient, so the inspired air is a blend of the supplied gas and room air. This is precisely what the option describes: the system can entertain room air along with added oxygen, which is the hallmark of an open system. A sealed system would prevent room air entry, and a choice stating it cannot entertain room air contradicts the open-system idea. The note about using only pressurized gas doesn’t specify whether room air is entrained, so it doesn’t define open in itself.

Open breathing systems are defined by allowing ambient room air to mix with the gases delivered to the patient, so the inspired air is a blend of the supplied gas and room air. This is precisely what the option describes: the system can entertain room air along with added oxygen, which is the hallmark of an open system. A sealed system would prevent room air entry, and a choice stating it cannot entertain room air contradicts the open-system idea. The note about using only pressurized gas doesn’t specify whether room air is entrained, so it doesn’t define open in itself.