Infection Control Today - 04/2002: Instrumental Knowledge

Flash Sterilization: A Questionable Practice Requires Proper Usage

By Michelle Gardner

The Association for Advancement of Medical Instrumentation (AAMI) defines flash sterilization as the process designated for the steam sterilization of patient care items for immediate use.

"As expected, flash sterilization has its pros and cons, but the latter have nothing to do with the efficacy of the process cycle," says Janet K. Schultz, RN, MSN, and president of consulting firm Jan Schultz & Associates. She refers to AAMI's flash standards which indicate that it is viable, and emphasizes that sterilization is a process, not a single event.

"Whether for flash or terminal processes, if there are compromises in cleaning, inspection, preparation of items and post sterilization cycle procedures, the efficacy of a process cannot be assured," says Schultz. "Flash has received a bad name, primarily because of misunderstandings or errors in processing. Adequate information and attention to the basics are needed, but the process is generally sound."

Some think shortened exposure times mean a compromise in efficacy. Steam sterilization without the air removal hindrance of a wrapper, however, is an efficient method. "Of course, items must still be designed to allow for air removal and steam penetration, and must be positioned properly in the sterilizer, especially if gravity displacement cycles are used," says Schultz. "The shortened exposure times used for gravity displacement cycles in flash are not a compromise in achieving the appropriate sterility assurance level (SAL) of 10^-6. Rather, they are a reflection of the faster heat up of the load, because air is rapidly eliminated from the unwrapped load. Exposure times for pre-vacuum and pulsing positive pressure units are the same for wrapped and unwrapped items because of the more efficient air removal in those cycles. The cycles set by the manufacturers of flash sterilizers have all been validated to achieve an SAL of 10^-6, just as those designed for wrapped goods."

Chris Lavanchy, ECRI's engineering director for the health devices group in Plymouth Meeting, Penn., describes flash sterilization as a process originally intended to be used as a last-ditch effort for sterilization.

"In some cases, hospitals have been using it more routinely than they should because it is convenient and quick," he says. "In theory, it shouldn't be a problem if you run through the cycle that is designed for flash sterilization. The problem is, there is no cleaning done beforehand (and items are) typically put right into the sterilizer. Secondly, there is no wrapping of the device. It is put into a container, put in the sterilizer, and comes out sterile, but it can be exposed to contaminants in the air as it is being transported to the operating room (OR)."

Lavanchy addresses the use of flash sterilization for implants of orthopedic devices like hips. "Complications associated with an infected implant are horrendous," he says. "But when it comes to implants, surgeons don't know exactly what size implant to use on a patient, so they are going to have a series of sizes. What they should be doing is sterilizing that series and choosing the one that is appropriate for the patient. Many states have regulations against flash sterilization for implants. Most hospitals recognize that (for implants) you should run a biological indicator with it to ensure you have met the conditions for sterility. With flash sterilization, you really are only going by measurements of temperature and pressure to ensure you have a sterile product."

Karen Huggins, RN, MN, CNOR, a clinical specialist at Presbyterian Hospital of Dallas, refers to the recommended practices of AAMI and the Association of periOperative Registered Nurses (AORN), which support using biological monitoring for flash sterilization daily. "Implantable medical devices should not be flash sterilized," she says. "If an implantable device is sterilized onsite, AAMI recommends that healthcare personnel quarantine the device and await the outcome of the biological monitoring."²

Huggins would not classify flash sterilization as a popular sterilization method, but quotes AORN Recommended Practices which states, "Flash sterilization should be used only in carefully selected clinical situations when certain parameters are met."

Why would healthcare facilities embrace it? "It's practical and convenient," says Huggins. "Financial constraints (may limit) instrumentation purchases, and there may be no other choice available in some institutions."

Why would they stay away from flash sterilization? "AORN does not recommend it except in carefully selected clinical situations," she continues. "Cleaning instruments appropriately needs to be addressed, and flash sterilization must provide a best practice standard."

Take the Direct Route

Unwrapped items must be transported from the sterilizer to the sterile field, and there is a perceived increased risk of contamination.

"Taking an item from a sterilizer to a substerile area immediately adjacent to the OR, in my opinion, does not represent any more risk of contamination than having open items in a busy OR during the start-up of a case," says Schultz. "Human shedding is a major source of contamination. If a particle lands on a wet or dry surface, the sterility has been technically compromised. 'Sterile field' is a term to designate the area where items and people must be subjected to appropriate aseptic procedures to minimize contamination."

Schultz indicates the real risks of transporting flashed items occur by touching an unsterile surface upon removal from the sterilizer, and exposing the items to areas where particulates or aerosols are higher than in the OR itself.

"The first is not likely to occur since OR nurses know how to avoid touching sterile items to unsterile surfaces," she says. "The second depends on where the flash sterilizer is located. Having a sterilizer in close proximity to a scrub sink would be problematic, as would transporting instruments through an area where items are being wrapped in linting materials. Carrying an open item through a group of staff not wearing masks could be an issue. If opportunities for contamination cannot be eliminated, one should consider using practices or devices that cover an item, either while in the sterilizer, or immediately thereafter. This is an easy challenge to resolve without a lot of resources. It is not a valid reason for not using flash sterilization."

Pros and Cons

Schultz mentions a number of benefits to flash sterilization, one being that it accommodates sudden changes in a procedure or resterilization of dropped instruments, thus allowing a patient's surgery to proceed safely.

"Changes in planned procedures, either subtle or radical, can occur at any time," she says. "Without flash sterilization, a procedure may be delayed since terminal sterilization requires not only the sterilization exposure, but drying and cooling down before an item can be handled. This generally means canceling a case until the next day."

A second benefit to flash sterilization is that it allows a facility to effectively rotate and use a limited instrumental inventory, thus providing cost savings. Says Schultz, "With appropriate flash sterilization procedures, it would be possible, for example, to do an unlimited number of cataract cases with just three sets: one in use, one being properly decontaminated, and one ready to be flashed for the next case. Some would say that two sets are enough, but that can shortchange the critical cleaning and inspection stage prior to sterilization."

A potential downside to flash sterilization is that, while efficacy is dependent on adequate cleaning, it usually is done in less-than-ideal situations, with OR staff rushing to process the items. "Items must be adequately cleaned, inspected and arranged for any sterilization process to be effective," stresses Schultz. "In the rush to get on with the case, this may be slighted. I heard of situations where uninformed staff will look at a device, and if no blood is visible, may just run it under water, or worse, place it in the sterilizer with no attempt to remove bioburden. But even more subtle compromises in cleaning can occur, like using solutions intended for surgical scrubs or antiseptic skin preps rather than enzyme detergents to process instruments."

Put It in Writing

Documentation of flash sterilization cycles is often lacking, compared to terminal sterilization loads, making identification and tracking of trends and problems more difficult.

"The documentation that accompanies every terminal load includes contents, cycle printout data and the identification of the person who (determined) the product can be released," explains Schultz. "For flash sterilization processes, not all hospitals keep the same information, although standard-setting bodies such as AAMI have included this requirement for more than 10 years. The time pressure in the OR works against this, and we need better ways to record and track this information in a busy arena. This data would be useful in determining instrument and staffing needs, and would be a variable in any investigation of an outbreak of infections."

Training in Flash Sterilization

In her article titled, "A Process for Improving Flash Sterilization," Huggins discusses the sterilization monitoring practices in the OR at Presbyterian Hospital of Dallas. In reviewing OR policies and procedures for flash sterilization, staff members discovered that their process of biological monitoring and flash sterilization needed improvement, and they implemented changes to correct the process.

Huggins says that, in general, training is being done, but there is a difference between training and educating. "I can train someone on the tasks involved in the sterilization process, however education on sterilization can be complex," she says. "Consequences of little training can mean we are getting and giving mediocre service, and someone is not able to troubleshoot effectively if anything extraordinary occurs."

Most sterilizers have cycles available for flash, and users must be able to match the device(s) to be processed with the appropriate cycle. Ideally, the information would come from the device manufacturer.

The delivery of sterile products for use in patient care depends on the efficacy of the sterilization process, efficient facility design, infection prevention practices, effective quality control and other aspects of device processing prior to, during and after sterilization.¹