Which type of sterilisation cannot be used to sterilise endotracheal tubes?

• A. Radiation
• B. Steam
• C. Hot air oven
• D. Ethylene oxide

Answer: (A)

The main idea is material compatibility: the sterilisation method must preserve the endotracheal tube’s integrity and function. Endotracheal tubes are made from polymers (like PVC) with a cuff that must stay elastic and leak-free to seal the airway properly. Ionising radiation can interact with these polymers, causing degradation such as changes in elasticity, embrittlement, or cuff failure. That risk means radiation sterilisation is not suitable for endotracheal tubes, because any compromise to the cuff or lumen could lead to air leaks or airway injury.

In contrast, steam, hot air, and ethylene oxide are compatible with the materials used in endotracheal tubes when applied correctly, so they can sterilise without compromising performance. Steam and hot air are common for heat-tolerant parts, while ethylene oxide is used for heat- and moisture-sensitive devices.