Which of the following is a controlled delivery device which is used to deliver a fixed concentration of oxygen?
**Core Concept**
The question is testing the student's knowledge of respiratory devices used in medical settings to deliver a controlled concentration of oxygen. The underlying principle here is the concept of oxygen therapy, which is used to increase oxygen levels in the blood, particularly in patients with respiratory or cardiac issues.
**Why the Correct Answer is Right**
The correct device is a **Venturi Mask**. It uses a jet of air to entrain room air and mix it with oxygen to deliver a precise concentration of oxygen, typically between 24% and 60%. This is achieved through a venturi valve that creates a pressure drop, allowing room air to be entrained into the oxygen flow. The Venturi Mask is commonly used in hospitals to deliver a fixed concentration of oxygen to patients.
**Why Each Wrong Option is Incorrect**
**Option A:** A simple face mask is not a controlled delivery device and does not provide a fixed concentration of oxygen. It simply delivers a flow of oxygen that the patient can inhale.
**Option B:** A nasal cannula is a simple device that delivers oxygen directly into the nostrils, but it does not provide a controlled concentration of oxygen.
**Option C:** A non-rebreather mask delivers a high concentration of oxygen, but it does not provide a fixed concentration like the Venturi Mask.
**Clinical Pearl / High-Yield Fact**
The Venturi Mask is a high-yield fact that students should remember, as it is commonly used in hospitals to deliver a precise concentration of oxygen. Students should be able to recall the Venturi Mask as a controlled delivery device that provides a fixed concentration of oxygen.
**Correct Answer:** C. Venturi Mask