The Importance of Using Validated Medical Devices and Consumables

The general requirements for the characterization of a sterilizing agent and the development, validation and routine control of a sterilization process are described in the standard ISO 14937.¹ Validation, the process that certifies and documents that a particular procedure meets the minimum requirements for which it was designed, is essential for all sterilization processes.² Medical device manufacturers (MDMs) and sterilizer manufacturers (SMs) should therefore validate that sterilization processes provide a sterilization assurance level (SAL) of 10^-6 for all relevant medical devices (MDs).^{2, 3} This sterility assurance is vital for infection prevention, specifically the prevention of healthcare associated infections, which are often attributed to the inadequate reprocessing of MDs.^{3, 4}

For every sterilization cycle, it is critical to ensure that each MD has been adequately reprocessed. Failures in reprocessing increase the risk of using a contaminated MD during a subsequent procedure. The use of a contaminated MD can compromise patient safety by increasing the risk of infection transmission; after the use of a Klebsiella pneumoniae-contaminated endoscope, 17 out of 68 of the exposed patients subsequently developed urosepsis.⁵ However, a considerable proportion of these healthcare associated infections, including surgical site infections, are considered to be preventable, highlighting the need for sterility assurance to maximise patient safety.^{3, 4}

To confirm that MDs can be adequately sterilized with a particular sterilization cycle and in a particular sterilizer, rigorous testing of each instrument is required, in collaboration with the SM and MDM. Two sterilization cycles, even if using the same sterilant, use a distinct combination of various parameters to achieve sterility assurance (e.g., concentration, exposure time, temperature). This combination of parameters also varies depending on the device(s) being reprocessed.³ Therefore, given this variation, it is incorrect to assume that two sterilization cycles using the same sterilant both provide sterility assurance for a given MD. Such generalization risks inadequate sterilization, which can ultimately risk exposure to infection.³

In order to ensure sterility assurance for each MD, validation that a process supplies effective sterilization is required.³

The validation of a sterilization process consists of installation, operational and performance qualifications. These steps ensure that sterilization is in keeping with the validated specification, whilst providing a SAL of 10^-6 for all MDs:²

• Installation qualification: the process of documenting evidence that equipment has been installed in accordance with the specification
• Operational qualification: the process of documenting evidence that equipment operates within pre-determined limits when used in accordance with the operating procedures
• Performance qualification: the process of documenting evidence that operational procedures consistently perform in accordance with pre-determined criteria, yielding the produce that aligns with the specification

It is necessary to validate all stages of a sterilization process, including cleaning, inspection, wrapping, packages, loading and unloading.² This is especially important at points where contamination may occur.² Transportation of sterile devices should also be considered, with the Association of Perioperative Registered Nurses (AORN) and the German Society for Sterile Supply both recommending that sterile items are contained within a validated sterile barrier system.^{6, 7}

To ensure that all MDs can undergo validated sterilization at all stages of reprocessing, responsibility must be shared between MDMs, SMs and health care professionals (HCPs). MDMs determine how each MD should be reprocessed in collaboration with the SM, who provide sterility assurance whilst ensuring material compatibility and functionality. Following validation, the method of reprocessing is confirmed by the MDM, who reflect this in the Instructions for Use. These instructions are followed by HCPs to ensure adequate reprocessing.³