Different outpatient surgery facilities employ flash sterilization, which is simply steam sterilization with no drying or packaging, quite differently. Some facilities flash sterilize single instruments that have become contaminated; others routinely flash anything and everything. Most follow protocols that are somewhere between these two extremes.

When you flash sterilize, you do need to take extra care to make sure the items are properly decontaminated, that the steam reaches all surfaces of the instruments, and that the items are not re-contaminated upon removal from the sterilizer. In this article, I'll explore the theory and practice of flash sterilization and present some guidelines to help you address these three important concerns. One note: This article will not attempt to define the circumstances under which flash sterilization is appropriate. There really is no good answer to that question that would apply to every facility.

Decontaminate Thoroughly
As with all types of sterilization, cleaning is the most important step-you cannot sterilize a dirty instrument. In Central Service departments, the decontamination activity appropriately takes place in a negative pressure area physically separated from the prep, pack, and sterilization areas. But too often, flash sterilization takes place in a busy, patient-care area, by staff that is not trained in proper cleaning techniques.

If you are routinely flash sterilizing complete sets between cases (which I do not recommend; it's better and safer to take the time to sterilize wrapped packs), you must dedicate a secured place and trained staff for the all-important job of decontamination. Make sure your staff understands the basics of how to separate clean instruments from dirty, disassemble and reassemble complex instruments, and properly use washer/decontaminators and ultrasonic equipment. Make sure the decontamination function is supervised by someone who has the time and training for the job.

Don't Overload
If you can sterilize a single surgical instrument in three minutes, you may think, why not sterilize two? Or three? Or perhaps an entire set?

The kinetics of effective steam sterilization require the steam to condense on the surfaces of the items being sterilized, where it gives up its latent heat to the object and then evaporates. It's this condensation and the associated heat transfer that allow items to be heated much more rapidly in steam than in dry heat. This evaporation creates a temporary vacuum that pulls fresh steam to the surface where more heat is transferred until a stable condition is reached (when the steam and the object being sterilized are the same temperature). This is called the conditioning phase.

The length of the conditioning phase will vary depending upon the amount of metal mass in the load, the source and quality of steam, and the type of cycle used (gravity, pre-vacuum, or steam-flush pressure pulse [s-fpp]).

If you load the sterilizer with too many instruments, or instruments that are too heavy, you will prevent this transfer of energy from occurring in the short amount of time that a typical flash cycle usually takes. Therefore, keep sets simple and the instruments spaced so that steam reaches all surfaces uniformly.

Do not attempt to flash sterilize power tools-there are too many hidden crevices and places to trap air. You can flash lumened instruments in gravity cycles for 10 minutes, pre-vacuum cycles in four minutes, and s-fpp cycles in three minutes. Make sure you open all hinged instruments and ratchets, disassemble all complex instruments, and place instruments with concave surfaces so that the surface does not pool water or trap air.

Never flash sterilize implantables. Implantables need to be quarantined until you obtain the results from the biological monitoring of the sterilization cycle.

Recommended Steam Sterilization Parameters for 270oF/1320C
Load Contents	Temperature	Gravity displacement cycles Time (min)	Vacuum-assisted cycles Time (min)	Steam-flush pressure pulse cycle Time (min)
Metal instruments; no porous items	270oF/1320C	3	3	3
Metal instruments combined with porous items (e.g. towels, rubber or plastic items, items with lumens)	270oF/1320C	10	4	3
Single wrapped instruments: no lumens or porous items	270oF/1320C	-	Express 4 minutes	3
Note: AAMI states, "Chemical indicators are not considered porous items. If used, the sterilization cycle does not need to be extended 10 minutes."

Transport with Care.
Because the sterilized items are hot and wet when the sterilizer door is opened, they are extremely susceptible to contamination by airborne particles. For this reason, you must protect these items from the time you open the door and as they travel from the sterilizer to the operative field. The distance from the sterilizer to the operative field should be as short as possible. Ideally, the sterilizer should be in the same room. Under no circumstances should you transport an open tray down corridors-not even so-called "sterile" corridors.

If the sterilizer is in another room, you need to protect the top and bottom of the tray from airborne contamination while en route to the sterile field. There are several ways to do this.

The least optimal but most often used option is to cover the tray with a sterile towel. If you use this option, have the sterile towel ready when the sterilizer door is opened. The towel should be large enough to cover both the top and bottom of the tray. Do not simply toss the towel over the sterilized items, rather, place the tray on one end of the towel and fold the other end over so that both the top and bottom of the tray are covered.

Another solution is to place a tray cover on its edge during the cycle and then simply use it to cover the tray before removing it from the chamber.

A better solution is to single-wrap the items and use a vacuum assisted cycle for four minutes or s-fpp cycle for three minutes.

The best solution is to use a flash approved container in a vacuum assist or s-fpp cycle according to the manufacturer's recommendations. Under no circumstances should you use a sterilization container in a gravity cycle unless and until you test your heaviest load with appropriate biological, enzyme, or chemical integrators placed inside the container wherever air can be trapped.

Final Thoughts
- Here are some of my own recommendations that I have formed over many years of observing flash sterilization activities:

- Use mesh bottom trays rather than solid or perforated trays. They sterilize and drain better.

- Do not attempt to cool down hot instruments out of the flash sterilizer by pouring sterile water over them-this is messy, cumbersome, and fraught with potential contamination problems. If handling hot instruments is a major problem, I recommend having a dedicated basin filled with sterile water handy so that the hot instrument can be dipped and then dried with a sterile towel.

- Do not "crack-the-door" and leave it open after the cycle to allow the contents to cool down. This allows the sterile hot air to rush out of the chamber and lets potentially contaminated cool air rush in over the hot, wet instruments. Always cover and bring out the instruments immediately after you open the sterilizer door.

- I strongly recommend against flooding gravity flash sterilizers. They do a good job of dislodging debris from the instruments but then allow the debris that is in suspension to reattach to the instruments as the water is drained. The hot steam then cooks the debris onto the instruments, which compounds the problem. If you have a flooding gravity flash sterilizer, I recommend using it as a boat anchor.

- Have enough instruments so that you do not have to rely on flash sterilization for routine sterilization between cases. Though this may represent an initial capital outlay beyond your current budget restrictions, it will pay off in the long run. Instruments will last longer and need to be repaired and replaced less often.

- Buy state-of-the-art sterilizers. Gravity displacement sterilizers were adequate when only sterilizing single instruments. Their limitations are exaggerated when trying to use them for routine (between each case) sterilization.

Flash sterilization, done correctly, is a safe and efficient sterilization method. But before doing it regularly, make sure you do the following:

- Develop protocols to ensure proper cleaning and decontamination, inspection, and arrangement of instruments into approved sterilizing trays or containers prior to sterilization.

- Ensure that the physical layout of the department or work area ensures the direct delivery of sterilized items to the point of use.

- Develop, follow, and audit procedures to assure aseptic handling and personnel safety while transporting sterilized items from the sterilizer to the using area.

Dan Mayworm is the former president of Mayworm Associates, Inc., and publisher of the Journal of Healthcare Resource Management and Infection Control & Sterilization Technology.