Certified Surgical Technologist (CST) Practice Exam

Which method is reliable for sterilizing surgical instruments?

1. Ultrasonic cleaning

2. Gas sterilization

3. Sodium hypochlorite solution

4. Cold sterilization

The correct answer is: Gas sterilization

Gas sterilization is recognized as a reliable and effective method for sterilizing surgical instruments. This technique utilizes chemical agents, such as ethylene oxide, which can penetrate packaging materials and reach areas that may be difficult to access with traditional moisture-based methods. This is particularly advantageous for heat-sensitive instruments that cannot withstand high temperatures, as gas sterilization operates at lower temperatures while ensuring a high level of sterility. The process typically involves placing the instruments in a sealed chamber where the gas is introduced. The instruments are then exposed to the gas for a specified period, followed by a thorough aeration phase, which reduces any residual gas left on the instruments. This method is widely used in healthcare settings due to its ability to effectively destroy a broad range of microorganisms, including spores, making it suitable for maintaining the sterility of medical and surgical instruments. Other options, while valuable in their own right, do not offer the same level of reliability for ensuring surgical instruments are sterile. For instance, ultrasonic cleaning is effective for removing debris and contaminants from instruments but does not perform sterilization, as it does not kill microorganisms. Sodium hypochlorite solution is primarily a disinfectant rather than a sterilant and is not suitable for all types of surgical instruments due to the potential for