Why is the cylinder closed when the pipeline supply is in use?

• A. To conserve gas
• B. To prevent cross-contamination of gases
• C. To avoid barotrauma
• D. To maintain constant pressure

Answer: (C)

The correct choice emphasizes the importance of cylinder management when the pipeline supply is in use. When the pipeline supply is providing the necessary gases for anesthesia, the cylinder is often closed to prevent potential issues related to pressure. Keeping the cylinder closed ensures that there is no backflow or unintended connection between the cylinder and the pipeline system, which could lead to differential pressures. If the cylinder were to remain open while the pipeline is actively supplying gas, this could create a risk of barotrauma in the patient, caused by excessive pressure from the cylinder that might inadvertently be transmitted through the system.

In addition, closing the cylinder prevents the risk of any gas from the cylinder mixing with the gas supplied by the pipeline, which may lead to inappropriate gas concentrations. It secures the setup, ensuring that the pipeline supply can deliver a steady and predetermined flow without interference from the cylinder's pressure. This also mitigates any risk associated with over-pressurization that could arise if both the cylinder and pipeline were inadvertently engaged.