Steam Sterilization Do’s and Don’ts

STANDARDS & REGULATORY WATCH Biomedical Instrumentation &Technology 483 Don’t: Substitute for BIs | Do: Document Everything | Don’t: Flash Sterilize Implants Steam Sterilization Do’s and Don’ts Saturated steam under pressure is one of the oldest methods used in healthcare facilities to sterilize medical devices. A new guidance document from AAMI—Comprehensive guide for steam sterilization and sterility assurance in health care facilities (ANSI/AAMI ST79:2006)—provides hospitals with guidance on every aspect of steam sterilization, from facility design to personnel considerations, through cleaning, decontamination, and sterilization, and concluding with quality assurance. This month, BI&T will examine the guidance ST79 provides in some key areas concerning steam sterilization safety and the sterilization of implantables: 1. Class 5 integrating indicators or enzyme-only indicators are not a replacement for biological indicators for loads containing implants. 2. Proper monitoring and documentation are essential to any sterilization and infection control program, and critical in cases where implants are released before the biological indicator test results are available. 3. Flash sterilization should not be used for implantable medical devices. Biological Indicators The use of biological indicators (BIs) provides evidence of efficacy of a sterilization process by challenging the sterilizer with a large number of highly resistant bacterial spores. Biological monitoring provides the only direct measure of the lethality of a sterilizer cycle. Sterilizer makers validate their cycles using BIs. While the performance of Class 5 integrating chemical indicators (CIs) and enzyme-only indicators has been correlated to the performance of BIs, these sterilization monitoring devices do not contain spores and thus do not directly measure the lethality of a sterilization cycle. They can, however, provide additional information about the attainment of the critical parameters of the sterilization process. BIs should be used with a user-assembled or commercially available disposable or preassembled process challenge device (PCD): to routinely monitor sterilizers at least weekly, but preferably every day that the sterilizer is in use; for sterilizer qualification testing after installation, relocation, malfunctions, major repairs, and sterilization process failures; and to monitor every load containing implants. Every sterilization load containing implants should be monitored with a PCD containing a BI (a BI challenge test pack). A Class 5 integrating CI or an enzymeonly indicator should be included in this PCD. ST79 bottom line: With respect to implantable devices, biological monitoring is necessary to provide optimal sterility assurance. A Class 5 CI or an enzymeonly indicator should be included with the BI in the PCD so that if an implant must be released on an emergency basis, additional information about the critical parameters of the sterilization process will be available and documented. Kurt Larrick Kurt Larrick is AAMI’s director of technical publishing and marketing. ANSI/AAMI ST79:2006 Implantables should not be flash sterilized. Every sterilization load containing implants should be monitored with a PCD containing a BI. Written documentation defining emergency situations in which an implant may be released before the biological indicator is available should be developed. Implant/implantable device: According to FDA, a “device that is placed into a surgically or naturally formed cavity of the human body if it is intended to remain there for a period of 30 days or more. FDA may, in order to protect public health, determine that devices placed in subjects for shorter periods are also ‘implants.’” [21 CFR 812.3(d)]. (From ANSI/AAMI ST79:2006) Load Monitoring, Release, and Documentation Physical monitoring provides real-time assessment of the sterilization cycle conditions and provides permanent records by means of chart recordings or digital printouts. Physical monitoring is needed to detect malfunctions as soon as possible, so that appropriate corrective actions can be taken. Every sterilization load should be physically monitored. Every packaged item should be labeled externally with a process indicator (Class 1 CI) and should contain an internal CI (Class 3 CI, Class 4 CI, Class 5 CI, or enzyme-only indicator). If desired, a PCD containing a BI (a BI challenge test pack) or a PCD containing either a Class 5 integrating CI or an enzyme-only indicator (a CI challenge test pack) may be placed in the area of the chamber and load considered least favorable to sterilization. The PCD should be equivalent to the BI challenge test pack described in 10.7.2.1 of ST79. As recommended above, every sterilization load containing implants should be monitored with a PCD containing a BI. Ideally, every reprocessed medical device, especially an implant, should be traceable to the patient on whom it is used or in whom it is implanted, and any load that includes implants should be quarantined until the results of the BI testing are available. Written documentation defining emergency situations in which an implant may be released before the biological indicator is available should be developed in consultation with infection prevention and control, the surgeon, and risk management. When documented medical exceptions dictate (e.g., the need for trauma-related orthopedic screw-plate sets), it could be necessary to release an implantable device before the BI results are known. In this case, according to ANSI/AAMI ST79: the release of the device before the BI results are known should be documented; and the BI result obtained later should also be documented. Releasing implants before the BI results are known is unacceptable except in limited, emergency situations. Emergency situations should be defined in written guidance developed in consultation with infection prevention and control, the surgeon, and risk management. Steps should be taken to reduce the frequency of emergency release of implantable items. For example, ongoing periodic reviews of the exception forms and implant logs could reveal consistent patterns of events that are causing emergency release and that could be corrected. (See ST79 for examples of an implant log and exception form.) Flash Sterilization of Implants Sterilization technology, even with its steady flow of advances and new equipment, does not solve the problems of using flash sterilization for implants. Concerns about aseptic transfer remain, especially if the sterilizer does not open directly into the room containing the sterile field where the device will be used or into an area either within or directly adjacent to the procedure room. Careful planning, appropriate packaging (e.g., packaging that allows the user to see the device for sizing and verification of features), and inventory management in cooperation with suppliers can eliminate the need to flash sterilize implantable items. This is a goal that all institutions should strive to achieve. For more information, refer to ANSI/AAMI ST79:2006. Steam Sterilization Do’s and Don’ts STANDARDS & REGULATORY WATCH 484 November/December 2006 ANSI/AAMI ST79:2006, Comprehensive guide to steam sterilization and sterility assurance in health care facilities. Order code: ST79 or ST79-PDF. List/Member price: $200/$100. Sterilization in Health Care Facilities, 2006-2007 edition. The new edition features several important additions to this essential hospital resource. Includes 15 AAMI documents; 1,046 pages. Order code: STBK06-1. List/Member price: $350/$250. AAMI Standards on CD-Sterilization Edition. The ultimate resource for sterilization professionals has been updated to include new material. Now features more than 50 current AAMI standards and guidance documents for sterilization on one CD. Order code: STBK-CD. List/Member price: $655/$475. TO O RDE R Phone (877) 249-8226, ext. 217, to order with a credit card Web Place your order at <A href="http://www.aami.org">www.aami.org</A> Source Code HI