Sterilization in a Flash

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Sterilization in a Flash
Not a quick fix, flash sterilization requires discipline to be effective

By Charles O. Hancock, RAC

Many OR users consider flash sterilization to be some kind of magic process that solves a multitude of inventory problems. In fact, use of flash sterilization requires discipline that few of its users follow. For those medical devices prepared for use by a Central Sterile Processing Department (CSPD), it is a given that sterility can be assured and documentation exists to confirm the status of those devices so prepared. Yet in spite of recommendation to the contrary1, flash sterilization is routinely carried out in operating rooms (ORs) every day, often without regard to process performance. Flash sterilization is the technique used today as an alternative to purchasing additional instrument sets or to save time when sterile instruments are required on short notice. Flash sterilization is, in some respects, an orphan process. No one wants to be responsible for recommending its routine use in the OR. Nevertheless, flash is widely used in the routine processing of devices within the OR. Personnel carrying out this flash sterilization process have other duties which are often considered to be more important than something so mundane as properly carrying out the complete, disciplined, multi-step process of decontamination and preparation of the instruments before sterilization. Such attention to the details of sterilization is left to the personnel in CSPD for all other goods. Users tend to forget that the flash sterilization cycle is short in time--often, an assumption is made that no barriers or minimum barriers to sterilant penetration are present in devices during a flash cycle. That may not be the case if the users have not paid careful attention to the reprocessing details required for flash sterilization. The instrument manufacturer may not have considered the particular requirements of flash sterilization when deeming the instrument as a reusable medical device. Since reprocessing or resterilization using flash is not a primary duty of those carrying out the process, they may be distracted by higher priorities from properly and correctly carrying out all of the steps necessary for a successful outcome. OR nurses and technicians are often overburdened with duties.

The exposure times recommended by sterilizer manufacturers are demonstrated to be effective when used strictly in accordance with their written recommendations. However, the sterilizer manufacturer assumes no responsibility for the preparation of the items to be sterilized, nor their proper placement within a tray or container, nor of the tray's placement within the sterilizing chamber. Nor do they assume any responsibility for the transport of the items to the point of use. Sterilizer manufacturers historically have considered flash sterilization as an act to be done under exceptional conditions. That is, that flash sterilization will be conducted only when a critical or emergency situation exists (i.e., the dropped instrument).

This assumption is erroneous. Rather than being the exception, flash sterilization is the rule in many ORs. (In 1999, one hospital's staff members said they carried out more than 33,000 flash procedures.4)

Consider that most hospital steam sterilizers are manufactured to meet the requirements of ANSI/AAMI ST8 Hospital Steam Sterilizers.2 This American National Standard was developed by the Association for the Advancement of Medical Instrumentation (AAMI) as a consensus standard reflecting the best information available and agreed upon by a committee of members representing users, producers, and general interest categories of expertise. As such, the standard is accepted by the US Food and Drug Administration (FDA) as a means of sterilizer manufacturers' compliance to special controls (in this case a consensus standard) applicable to Class II medical devices. A hospital steam sterilizer is a Class II medical device. The FDA requires premarket notification [510(k)] before a hospital steam sterilizer can be introduced to the market. Part of the information required of the manufacturer for conformance to ST8 is the documentation of biological testing results specified in the standard. Note that ANSI/AAMI ST8 currently does not require testing of a "flash" or unwrapped goods cycle.

Load Specifications

The standard requires and specifies the testing of three types of loads. They are: the fabric test pack, liquid loads of three one-liter flasks (if applicable), and a wrapped instrument test pack. Also note that there is currently no requirement in the standard for a manufacturer to demonstrate a flash cycle. However, most steam sterilizer manufacturers do make available a recommendation for a flash cycle based on testing they have done. That testing defines an unwrapped (or a single wrapper with special instructions) load of specified size to establish a cycle of sufficient lethality to provide a sterility assurance level of 10-6. That testing may be for a simulated small load or even for a single item. Caution should be exercised by the user, since some manufacturers may not have test data to support the processing of large tray loads such as those typical in orthopedic instrument processing. The user should strictly adhere to the sterilizer manufacturer's written recommendations with respect to that load. If the manufacturer has not provided such documentation, ask for it. In any event, the user should validate through a performance qualification that the loads being processed are actually being subjected to sterilization condition in the configuration presented within the sterilizer chamber. Any significant changes to that load should be carefully validated to ensure that the flash process used will sterilize.

The steam sterilizers available and used today for flash sterilization in hospitals today are designed to be efficient, reliable, and effective when operated within the manufacturer's recommendations. But, as flash sterilizers are used and misused, their use may not represent good sterilization practice as understood by the experts in the field--those responsible for sterilization in CSPD. There is hope for the user in that AAMI has also provided a recommended practice that covers flash sterilization in hospitals. ANSI/AAMI ST37 Flash Sterilization: Steam Sterilization of Patient Care Items for Immediate Use1 was developed to answer this need. This recommended practice concentrates on what is needed to ensure that flash sterilization is safe and effective. Work practices are described reflecting the complete process of sterilization as a guide to those not having a sterilization background. The physical layout of the facility is considered to provide reference for those planning revision to old or design of new facilities. There is also discussion regarding procedures to assure aseptic transfer of sterilized items from the flash sterilizer to the point of use in the sterile field. Appreciate that a recommended practice such as ST37 should serve as a guide for those interested in moving toward performance objectives intended to bring the practice of flash sterilization more closely into agreement with those practices generally accepted for the sterilization of reusable medical devices.

When considering any medical/surgical instrument as a reusable device, one looks to the manufacturer of the instrument for advice and instructions on how to reprocess that item. That information is especially important when contemplating an instrument to be a candidate for flash sterilization. The flash sterilization process is a multi-step process that requires meticulous attention to detail for success. Failure to decontaminate and clean an instrument properly can defeat the process. The instrument manufacturer is obligated to provide the user with at least one method of reprocessing if the device is labeled for reuse. The method described, however, may not be compatible with your flash sterilization procedures. The proper disassembly of complex devices is one of the most difficult manufacturer recommendations to meet for users. Written procedures are frequently not specific enough to ensure all instruments are consistently and properly prepared for flash sterilization.

Of particular concern is the sterilization of implantables. Flash sterilization of implantables is not recommended.3 Orthopedic sets are typically one of the most frequently flash sterilized sets of instruments. The items necessitating flash sterilization in those orthopedic sets are items that are implanted in the patient (i.e., screws).

Careful analysis of items being flash sterilized can potentially identify alternative solutions that may reduce the number of flash sterilization cycles being used. For example, if information is collected that accurately reflects the items being added to a set that then requires flash sterilization, the reasons for using flash sterilization can be identified. The follow-up action required is to acquire enough of those items to eliminate the need for flash cycles.

In addition to providing written documentation of work practices for users to ensure proper cleaning and decontamination, inspection, and the arrangement and packaging of instruments in trays to be sterilized, it is recommended that any OR conducting flash sterilization start tracking by cycle what trays were processed and why the flash cycle was needed. This analysis will serve to document the specific needs that must be met to reduce the number of flash cycles being run. By recording the reason for performing the flash cycle, a database may be developed that will aid in establishing a rationale for eliminating the need for the flash cycle in the first place. Often, a small investment in purchasing additional individual single-use items may result in a significant reduction in the number of flash cycles being carried out. If those flash cycles being eliminated are cycles containing implants where biological monitoring is required, a significant cost reduction can be realized over time. Anecdotally, the hospital referred to earlier used this technique to reduce the number of flash cycles from about 33,000 per annum to less than 22,000 in one year's time.4

Normally OR personnel are too busy to record information concerning their use of flash sterilization. But they certainly would be happy if they didn't have to run one of every three flash sterilization they run today. OR managers are well advised to look at means of eliminating activities such as flash sterilization since that is the only true means of eliminating labor costs.

Charles O Hancock is the president of Charles O. Hancock Associates, Inc. in Fairport, NY.
To receive a copy of the ANSI/AAMI ST8 visit
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