The Sterilization Future

Over the past 25 years, sterilization has evolved to keep pace with the medical device industry. Although sterilization technologies themselves have remained unchanged in their physics and chemistry, some significant developments have advanced the methods and processes. The future promises to offer even more substantial developments. Key developments in the sterilization market as a whole should include:• Changes in the sterility assurance level (SAL) requirements for various device groups. Internationally, the requirement for a device to be labeled with a “sterile” statement requires a SAL of 10–6. In the future, this requirement may be revisited to allow products with alternate SALs (i.e., 10–3, 10–4, etc.), based on the need for such elevated SALs and on product use. • Alternative gaseous-sterilization modalities, such as vapor-phase hydrogen peroxide and plasma vapor-phase hydrogen peroxide, offered on a contract basis.• An overseas exodus of sterilization similar to that of device manufacturing.• Modalities that are less energy dependent (i.e., more cost-effective) to combat spiraling energy costs.• Improved manufacturing controls that reduce bioburden spike issues.• Documents from the standards-writing groups covering how to deal with bioburden spikes.• Rapid environmental monitoring techniques for manufacturing. • Further harmonization of international methods. Major advances affecting EtO sterilization and processing include:• BIs that offer essentially instantaneous response times.• Further developments in parametric release for EtO sterilization.• Evolution of the industry guidelines for validation. Developments in gamma sterilization will likely include:• Final development and implementation of VDmax guidelines at doses other than 25 kGy with validation using this technique from 15 to 35 kGy.• Evolution of the industry guidelines for validation. In 2004, the next revision of the AAMI 11137 standards should be released: AAMI 11137-1 draft standard, “Process Requirements for Radiation Sterilization;” AAMI 11137-2 draft standard, “Validation Methods for Radiation Sterilization;” and AAMI 11137-3 draft standard, “Dosimetry for Radiation Sterilization.”• No sterilization dose validation requirement for devices with proven very low bioburdens.• Predictive dosimetry using mathematical modeling that is based on the application of knowledge and computer power currently available.• Parametric release for irradiation processing. Cost-competitive pressures and improved science (based on enhanced computer control and real-time dose-measurement systems) may drive this feasible methodology forward.• Alternative dose-setting strategies, further increasing the options available to the sterilization microbiologist.Laboratory advancements should include:• Rapid microbiological methods that reduce the time needed for bioburden assessment from about a week to a day. The technologies already exist, but they will come into common use as regulatory acceptance, awareness, and their utility become better known.• Genetic-based microbial identification methods as the standard for identification of environmental isolates, bioburden tracking, and failure investigations. • Technology improvements such as isolators, cleanroom HEPA-filtered respirators and improved barrier gowns and gown materials that increase the reliability of existing sterility test methods.• New rapid microbiological methods that replace the existing sterility test procedure.With these developments, sterilization will continue to be an integral part of the medical device industry. As it has in the last 25 years, we are sure that MD&DI will bring you updates and developments as they happen in the next 25 years.