What is a Process Challenge Device?
Process challenge devices (PCDs) are contrivances used in the course of sterilization validation to assess the effectiveness of a sterilization procedure. PCDs monitor and ensure the items are subjected to effective sterilization without directly using the item itself. PCDs are typically inexpensive medical devices like syringes loaded with indicator microorganisms that are more challenging to sterilize than the device undergoing sterilization validation.
Why Use Process Challenge Devices?
Testing the actual medical device for sterility is expensive, risky, and affords no margin of error. Some sterile medical devices are very expensive and the process of testing them directly for sterility is cumbersome and sacrifices the medical device in the process. In response to the risk of reintroducing contamination to sterilized items when testing the sterilization process’s effectiveness, process challenge devices (PCDs) were developed. PCDs are used in conjunction with sterilization to monitor and ensure the items are subjected to effective sterilization without directly using the item itself.
Two Components of Process Challenge Devices
PCDs generally have two components: a barrier component and a sterility assurance indicator. The barrier is also termed as an “outer package” and is purposefully made to be difficult to sterilize. The sterility assurance indicator is inside of the barrier and is usually a self-contained biological indicator. A chemical indicator may be additionally included if wanted, but typically only a biological indicator is used. The biological indicator is typically a piece of material that is inoculated with a known concentration of a known microorganism. The indicator microorganism is usually assumed to be more resistant to the sterilization process than the usual contaminating microorganisms. When the process is completed, the biological indicator is assessed for growth. If no growth is observed, then it is highly probable that any microorganisms present on the item prior to sterilization have been inactivated/killed thus ensuring that sterilization has been achieved.
Sources:
Kirckof, S. (2008). Process Challenge Devices: Validating Sterilization. Biomedical Instrumentation & Technology, 42(4), 309-311. https://doi.org/10.2345/0899-8205(2008)42[309:PCDVS]2.0.CO;2
