Infection Control Today: OR Topics

Sterility Assurance Through Quality Control
By Heide Ames, BS, and Sandra Lee, BSM, RN

Sterility assurance plays a veryimportant role in the delivery of quality patient care. In healthcare facilitiesworldwide, sterility assurance activities in the central service (CS) departmenthelp reduce the possibility of cross-contamination and the risk ofhealthcare-acquired infections. A comprehensive sterility assurance program isessential for effective infection control. Every step of the sterile processingcycle, from instrument handling in the operating room (OR) throughdecontamination, preparation, sterilization and sterility maintenance, should beaudited and/or monitored for quality to effectively support optimal patientoutcomes.

A critical part of this process is the chemical and biologicalmonitoring of steam sterilization cycles. Testing standards and recommendedpractices are provided in documents from the Association for the Advancement ofMedical Instrumentation (AAMI) and the Association of periOperative RegisteredNurses (AORN). These recommendations apply to any department or organizationthat sterilizes items for use in patient care.

In todays world of sterile processing, the CS or OR manageris not only responsible for ensuring that each instrument, basin and textilepack is processed, but that all processing tasks are completed efficientlyfollowing AAMI standards and recommended practices. This sometimes leads toperceived conflict between the AAMI standards and the continual pressures toincrease productivity, which can lead to shortcuts that may jeopardize patientsafety. For example, how many times have implantable devices been released priorto knowledge of the bacterial growth result? How often have in-pack indicatorstrips not been used?

CS and OR managers do not have to lose sleep at night worryingabout how to monitor their processes properly while maintaining productivity.The correct mix of biological and chemical indicators, along with a little bitof planning and documentation and an AAMI quality control program, will helpprovide a high degree of sterility assurance and patient safety in an efficientmanner.

A Good Quality Control Program Starts With the SterilizationEquipment

All steam sterilizers need to be verified for proper functionon a regular basis. This means that a microbial challenge must be processed inthe sterilizer weekly, and preferably daily, for each type of cycle that is runin that sterilizer. The microbial challenge must be in a test pack sufficient tocreate a difficult challenge to the sterilization process. Considering that the average sterilizer has at least two typesof cycles and usually two temperature choices, this testing quickly devours timeand money. In addition, the incubation periods for spore outgrowth requirebetween 24 hours and seven days, so the microbial testing can become even moretime-intensive and costly.

This time frame can be shortened considerably usingalternative monitoring technologies. Though AAMI standards still require aweekly spore outgrowth test, the remaining days of the week can be monitoredwith:

  • A biological indicator (BI) with enzyme-basedearly-readout capabilities

  • Multi-enzymatic products (without a biologicalindicator)

  • Class 5 integrator products

All of these should be placed withinappropriate challenge packs for this testing.

Not only do all of these systems meet AAMI standards andrecommended practices for a weekly conventional spore outgrowth test; they alsoprovide the fastest daily equipment check: one to three hours using biologicalindicators with enzyme-based early-readout capability; 20 seconds formulti-enzymatic products; or immediate results using integrator type products.

In addition to microbial challenges, steam sterilizers usingpre-vacuum cycles must also complete air removal tests as part of equipmentquality control. In this case, preassembled disposable test packs can provideadvantages for the user. First, preassembled disposable test packs may actuallycost less than self-constructed Bowie Dick test packs (although this is not acommon perception) since self-constructed pack costs include the laborassociated with washing and folding towels and the final assembly of each testpack. In addition, the inconsistencies among construction techniques forself-constructed packs can lead to questionable or invalid results.

Processes to Release Sterilized Items

To guard against equipment and process failures during theday, several products have been developed to monitor the performance of eachcycle and provide assurance of a sterile process prior to a loads release foruse. The goal of any of these products is to provide assurance that all criticalparameters of sterilization have been met within an appropriate test pack.Traditionally, this test has been conducted with a BI test pack requiring 24hours to seven days to provide final results. However, the newer alternativemonitoring products described above provide the same information more quickly. The fastest of these is the Class 5 integrator challenge pack.

Although integrator challenge packs are equivalent tobiological indicator test packs, the AAMI Standards and Recommended Practicesdocument recommends not using integrator challenge packs for the release ofimplants. A biological indicator with conventional spore growth or with anenzyme-based early-readout capability must be used for this purpose.

In order to optimize turnaround time, both types of packsshould be used: integrator challenge packs for the majority of cycles those without implants in the load and BI test packsfor the few cycles with implants. Efficiencies can be further improved byplanning for the processing of all scheduled implantable devices to be done inone or two separate loads.

Occasionally, a medical emergency may occur in which animplantable device is needed immediately, before the final biological indicatorresults are available. In such cases, the implants may be released as long asthe early release is documented by the sterilizer operator, and the operatorreviews the sterilizers cycle printout and other indicators used to monitorthe cycle. BI test packs containing a Class 5 integrator provide immediateassurance that all the critical parameters of sterilization have occurred, whichare correlated to the death of the organisms on the biological indicator.Ultimately all results must be recorded and the early release documented perAAMI standards (ST 46 and ST 37).

Quality Control of Packs

Although the load release monitoring products described aboveprovide information that the sterilization cycle completed satisfactorily, theydo not address the conditions within each pack. Successful sterilization of theitems within a pack is dependent on thorough decontamination, properpreparation, proper packaging, and appropriate placement of items in thesterilizer. A non-sterile pack could lead to considerable cost ramifications forboth the hospital and the patient if a healthcare-acquired infection occurs.

The best way to control the quality of packs is to use in-packmonitoring with Class 5 integrators. These products confirm that the internalconfines of the pack were exposed to all the critical parameters necessary tokill a BI.

Documenting Your Program

Of course, a quality control program will not be effectiveunless all data is documented. Establishing and following policies andprocedures, including the recording of the results of all the tests we havediscussed here, are critical for maintaining quality awareness and proceduralconsistency in a sterility assurance program. Both written formats and computerprograms are available for documenting and tracking a departments criticalprocess monitoring data. The bottom line is: documenting everything helps toensure that no sterility failures are missed.

Sterility assurance is critical in any quality control programfor limiting the risks associated with cross contamination andhealthcareacquired infections. CS and OR managers can operate an efficient,consistent, and reliable sterility assurance program by following AAMI standardsand recommended practices. By executing those guidelines with effectiveplanning, proper use of todays new technologies, and the right combination ofbiological and chemical indicators, any CS department and OR can maintain bestpractices while improving overall efficiency. ICT

Heide Ames, BS, is associate product manager, and Sandra Lee,BSM, RN, is senior manager of professional education for the STERIS Corporation.

Epidemiologists Trace Outbreak of Antimicrobial Resistant Organism

BALTIMORE, Md. Infection control experts at the Johns Hopkins Hospital (JHH) say tighter rules governing use of a hand-held, highpressure, water-pumping tool to wash and clean wounds should be adopted to improve the safety of wound care. The Hopkins finding comes in response to the investigation of an outbreak of the antimicrobial-resistant bacterium Acinetobacter baumannii at JHH during a two-month period in 2003. The organism infected 11 patients and was traced back to use of pulsatile lavage equipment for wound care. Three of these patients required admission to the intensive care unit for sepsis and respiratory distress.

In the future, staff using the water-gun like equipment will have to wear masks, gowns and gloves during procedures, which must also now be performed in private treatment rooms that are fully disinfected between patients to reduce the chances of cross contamination between patients and staff. As an added response, the Food and Drug Administration (FDA), which supervises device safety, along with a leading manufacturer of the device, have agreed to change the products labeling to include use of routine infection control procedures.

Hopkins already has instituted the new infection control procedures. Changes at Hopkins and results of the study should change the way this common procedure is performed at other acute-care hospitals and long-term care facilities, says senior study investigator and hospital epidemiologist Trish Perl, MD, an associate professor of medicine and pathology at the Johns Hopkins University School of Medicine.

The Hopkins case study is believed to be the first investigation to relate an outbreak of this bacterium to the pulsatile lavage device, and its results were published in the latest edition of the Journal of the American Medical Association online Dec. 22, 2004.

The Hopkins investigative team traced the infection to the pulsatile lavage tool made by Bard-Davol Inc., and determined that the equipment sprayed the potentially dangerous bacteria into the air and onto surfaces in an open treatment room, with other patients nearby.

This was true even though staff correctly followed procedures for its use, Perl adds. Germs were spread when patients and staff came in close contact with each other during procedures and possibly when fewer equipment parts were changed between patients. Guidelines for its use also applied only to healthcare workers, not to patients, prior to the outbreak.

Since finding the cause of the outbreak at Hopkins, the specific strain of the bacterium involved in the outbreak has not reappeared, even after 11 months of follow-up testing.

Antimicrobial resistance is a growing problem for patient safety in healthcare settings, such as hospitals and long-term care facilities, because traditional drugs are not effective for treating these infections, particularly among vulnerable groups of sick and elderly patients, Perl notes. To solve the problem, we are increasingly forced to rely on our basic tools of scientific investigation: finding the initial contact point, or source, of infection and putting in place the necessary steps to prevent an outbreak from happening in the first place.