Which statement about depressing the manual vent is correct?

• A. It should be depressed only when suction is connected and operating
• B. It should be depressed any time to speed up drainage
• C. It should never be used
• D. It should be kept closed at all times

Answer: (B)

The main idea is how the manual vent changes the flow path in a chest tube drainage system. Depressing the vent opens an air pathway to the atmosphere, which reduces resistance in the system and allows air and fluid from the chest to escape more readily. By providing this quick release path, drainage can be speeded up whenever you want or need faster removal, such as when suction isn’t actively pulling fluid or when rapid drainage is indicated. The other thoughts—only using it with suction, never using it, or keeping it closed—don’t align with how the vent is intended to function to enhance drainage.