With a venturi mask, which accessory helps prevent accidental increases in FiO2?

With a venturi mask, which accessory helps prevent accidental increases in FiO2?

• A. bag
• B. cup
• C. cap
• D. valve

Answer: (B)

The main idea is that a venturi mask delivers a precise FiO2 by using a calibrated jet that entrains room air. Small changes in mask fit, breathing pattern, or accidental flow tweaks can cause the delivered FiO2 to drift upward. An accessory shaped like a cup provides a stabilizing enclosing space around the jet/entrainment area, helping maintain the intended mixing ratio and reducing the chance that the FiO2 will rise unintentionally. In other words, the cup helps keep the delivered oxygen concentration consistent with the setting. The other options don’t offer this stabilization: a bag is associated with non-rebreather configurations and can alter flow dynamics, while a cap or valve doesn’t specifically stabilize the entrainment process to prevent accidental FiO2 increases.

The main idea is that a venturi mask delivers a precise FiO2 by using a calibrated jet that entrains room air. Small changes in mask fit, breathing pattern, or accidental flow tweaks can cause the delivered FiO2 to drift upward. An accessory shaped like a cup provides a stabilizing enclosing space around the jet/entrainment area, helping maintain the intended mixing ratio and reducing the chance that the FiO2 will rise unintentionally. In other words, the cup helps keep the delivered oxygen concentration consistent with the setting. The other options don’t offer this stabilization: a bag is associated with non-rebreather configurations and can alter flow dynamics, while a cap or valve doesn’t specifically stabilize the entrainment process to prevent accidental FiO2 increases.