PSI NBSTSA Certified Surgical Technologist (CST) Practice Exam

The use of a biological indicator in the context of preparing endoscopic cameras for ethylene oxide sterilization is crucial for ensuring that all sterilization parameters have been met. Biological indicators contain a known quantity of viable microorganisms that are highly resistant to the sterilization process. After the sterilization cycle is complete, the biological indicator is incubated and monitored for growth. If no growth occurs, it indicates that the sterilization parameters — such as exposure time, temperature, and concentration of ethylene oxide — were adequate to eliminate the microorganisms present, thus validating the sterilization process.

This method is considered the gold standard for confirming the effectiveness of sterilization because it directly assesses the lethal effect of the sterilization process on living organisms, which is a critical aspect of ensuring patient safety and the sterility of surgical instruments. In contrast, other monitoring processes, while useful, do not provide the same level of assurance regarding the actual lethality of the sterilization method employed.