Medical Design Briefs - December 2022 - 8

Sponsored Content
INSIDE STORY
Ethylene Oxide (EO) Sterilization may be the only method that effectively sterilizes heat- and moisturesensitive
medical devices without damaging the device during the sterilization process. Medical devices
made from certain polymers (plastic or resin), that have multiple layers of packaging, or hard-to-reach
places (for example, catheters) are likely to be sterilized with ethylene oxide. To find out more about the
expertise required to establish a safe and effective EO Sterilization for medical devices, MDB recently
spoke with Elizabeth Sydnor, Director of Microbiology, for Eurofins Medical Device Testing (Lancaster, PA).
MDB: With upcoming changes to the U.S. environmental regulations,
is that going to impact the use of EO moving forward?
Elizabeth Sydnor: There are many
regulations regarding the use of
EO. Specifically, the Environmental
Protection Agency (EPA) has concerns
regarding the amount of EO emissions.
There are established regulations, such
as the Clean Air Act, for facilities releasing
certain chemicals into the air.
This impacts EO sterilization facilities
and will continue to change the industry
over time as a result. There will be some considerations
that we will have to watch, but I believe that we'll be using EO
to sterilize medical devices for years to come. Eurofins Medical
Device Testing's laboratories will not be impacted from a device
testing perspective by these potential changes.
MDB: Are EO validation standards applicable to the EU?
Sydnor: AAMI is an accredited organization by American
National Standards Institute (ANSI), which ensures that the
procedures meet essential requirements. The International
Organization for Standardization (ISO) standards and other
industry guidance documents are widely used and leveraged in
the EU and the United States, as well as many other countries.
Eurofins Medical Device Testing's laboratories are ISO 17025
accredited and capable of testing to industry standards and
guidance documents to assist in EO Sterilization validations.
MDB: What organism is a concern for EO sterilization?
Sydnor: Bacillus spores are the most resistant species to EO
gasses. One of the common biological indicators used during
the validation of an EO cycle is Bacillus atrophaeus.
MDB: How soon should a lab get involved during the validation
process?
Sydnor: The laboratory should get involved immediately. There
may be other considerations that potentially need testing,
such as packaging or biocompatibility. Reaching out to our
laboratory right away to begin collaborating will help you set
up a program that checks all the boxes needed to ensure that
necessary testing is understood upfront.
MDB: If a sterilization cycle is validated, is additional quarterly
audit testing needed?
8
Sydnor: This will be different from a gamma sterilization validation
where quarterly dose audit testing is common. For EO, there
is routine testing that would be required for the sterilization
validation. EO is validated using Annex B, which is the overkill
approach. This would cause a parametric release, which is normally
done by a biological indicator, or process challenge device
(PCD), which is a representation of the load after each cycle.
MDB: How often is revalidation or product testing required?
Sydnor: Normally, you consider revalidation if there is a change to a
process or product. Depending on the outcome of that assessment,
validation could be required along with other testing. As for product
testing, this would be required after each lot release. For every lot
released, there is a requirement to show the cycle has been successfully
completed and rendered the product sterile. Product testing
will happen routinely; however, revalidation is subject to change.
MDB: How would the relevance of AAMI TIR28: 2016/
(R)2020 - Product Adoption and Process Equivalence for
Ethylene Oxide Sterilization when audited by notified body
correspond with the overall validation process?
Sydnor: This technical report focuses on making changes to an existing
validated cycle or adding a new product into an existing cycle.
MDB: Can you give some information on how to select a PCD?
Sydnor: ISO 11135 provides items to consider about a PCD. It
states in Section 3.28 Note 2: " In this International Standard,
a distinction is made between an internal PCD and an external
PCD. An internal PCD is used to demonstrate that the required
product Sterility Assurance Level (SAL) is achieved. A PCD
located within the confines of the product or product shipper
case is an internal PCD, whereas a PCD located between shipper
cases or on the exterior surfaces of the load is an external PCD.
An external PCD is an item designed to be used for microbiological
monitoring of routine production cycles. "
MDB: How often do EO sterilization processes, parameters,
etc. have to be revalidated?
Sydnor: Requalification should be assessed and documented based
on the outcome of the review. ISO 11135 gives guidance on this,
along with items to consider. This should be performed at least
every two years per the " Requalification " section of the document.
To learn more about Eurofins Medical Device Testing, visit
www.eurofins.com/medical-device.
www.medicaldesignbriefs.com
Medical Design Briefs, December 2022

http://www.eurofins.com/medical-device http://www.medicaldesignbriefs.com

Medical Design Briefs - December 2022

Table of Contents for the Digital Edition of Medical Design Briefs - December 2022