The Rigid Container Story: Looking Back to the Future

June 1, 2002

The Rigid Container Story: Looking Back to the Future

The Rigid Container Story: Looking Back to the Future

By Bryant C. Broder, CSPDT, ACSP

Rigidcontainers were first developed in Tuttlingen, Germany in the mid-1890s. Theseoriginal containers were made of stainless steel, but chrome-plated containers(in response to the needs of military hospitals and aid stations) had become thecontainer of choice by the early 1900s. The main function of these earlycontainers was to transport sterile instruments and dressings. In that era itwas not unusual for sterile supplies to be kept in a few containers for anentire day's operating schedule. At about this time the first steam sterilizerwas created: the "Schimmelbus." Steam and container working as oneproved to be the most effective sterilization method for the operating room atthe beginning of the 20th century.

It wasn't until the early 1930s when reusable filters were introduced,replacing existing valves and sliding vents. Rubber gaskets were added shortlythereafter to ensure a more effective seal between the lid and container bottom.In the 1960s anodized aluminum containers were introduced, providing optimalheat transfer properties. The lightweight anodized aluminum construction allowedfor easy handling and stacking. As technology advanced, disposable non-wovenfilters replaced textile filters within containers as a more secure barrier.

At the Association of Operating Room Nurses Congress in 1980, the concept of"rigid packaging for sterilization" was introduced in the UnitedStates. This new and exciting concept positioned itself directly opposite thetraditional wrap. The paper or cloth packaging originally employed forinstrument sets was challenged for the first time. Several issues emerged: microtears along paper edges, sterility during transport and excessive moistening ofthe sets (due to the limited drying capacity of the material). Hospitalmanagement became increasingly concerned about the high costs associated withdisposable paper sterilization wraps.

With time, sterilization containers gained the confidence of hospitalprofessionals. They are both durable and cost-effective, aid in set organizationand they tend to protect instruments better than wraps. There are dozens ofdifferent container sizes and shapes to accommodate most commonly usedinstruments. From instruments to scopes to drills to cameras, varying containersizes seem to offer a viable alternative to wrap. Yet, with all of the recentpopularity and all of the history, questions still remain. "Are containerssafe?" "Are they really cost-effective?" And, "Whatcontainer system is best for me?"

First, let's examine what we know about our sterilization needs:

  • Safe, effective and reproducible sterilization of equipment is a critical component of patient care in today's operating room.

  • The supply of sterile equipment places high demands on quality management regarding sterility, hygiene and infection prophylaxis in hospitals.

  • Sterilization of instruments and equipment should be cost-effective.

  • Handling of sterile equipment should be simple, fast and safe.

The Safety Issue

When considering issues related to safety and containers, familiarity withthe manufacturer's sterilization validation studies is paramount. Sterilizationvalidation is a test conducted by the manufacturer that demonstrates thesterility of container contents under defined parameters. The manufacturershould be able to provide data proving that instrument sets can be sterilized intheir containers -- including information about load weight, type of process andlength of cycle. The manufacturer should also be able to provide a copy of itsFDA-approved 510(k) clearance as a Class II device. If a container will bestored for an extended period before use, make sure to find out what shelf-lifedocumentation the container manufacturer can provide.

Based on the history of the product, safety-relevant design features must beincorporated into the construction of the system. Relevant tests and validationprocedures must confirm safety aspects, especially the all-important microbialsafety of a container.

Some points to ponder:

  • Make sure the bottom and lid secures the sterilized goods against mechanical damage and thereby against recontamination after sterilization during transport and storage.

  • Develop a "worst case" limit at your institution for set load. This may be based on the manufacturer's recommendations or your own experience.

  • The container design allows it to stay germproof after sterilization, during transport and during storage. Below are three basic requirements of the filtering system:

1. Change of atmosphere during the steam sterilization phase. Physicalrequirements: air and steam must pass with a low flow resistance.

2. Cooling-down phase outside the sterilizer. Physical requirements: hot airinside the container cools down, non-sterile air will be sucked into thecontainer, which must enter the container without contaminating the contents.During the cool-down phase a huge volume of air has to be filtered back out.

3. Transport and storage phase. Physical requirements: under load and duringtransport, due to atmospheric pressure differences, there is a pressurecompensation and therefore an exchange of a small volume of air. The filteringsystem must allow this without allowing contamination. During transport thereare vibrations, and there is a rapid change of volume. The filter must workefficiently and effectively during transport.

Assuming the validation process is satisfactory and meets all FDArequirements provided to you by the manufacturer, the next logical question is:"Is 'containerizing' cost-effective?"

The Cost Issue

The initial cost to the capital budget regarding the process of converting tocontainers can be overwhelming, and this has prevented many institutions fromadopting the technology. If a large capital-budget expenditure is a concern,some manufacturers offer monthly payment programs designed to move containersinto the hospital's operating budget. Even in this situation, it may bedifficult to justify the container expense to management. When making such aninvestment, one must consider the long-term financial return. Containers savemoney mainly by lowering expenses associated with wrap, but for some sets thissavings may not be enough to justify the container investment.

Consider the "soft cost" savings of containers as well:

1. Lower risk of instrument damage, lower risk of loss

2. Excellent storage space utilization (stacking of sets)

3. More efficient transfer from facility to facility

4. Fewer packaging material integrity breaches

5. Easier back-table setup in the operating room

The first step to analyzing the costs associated with containers is to lookat the facility's usage of high-volume sets. Some hospitals require that aninvestment such as this return savings equal to the acquisition price within aset period, known as the "payback" period. This period will vary basedon the financial models used at your institution, but many use an 18-month totwo-year period for payback to justify an expense. To calculate a simple paybackfor your set, use the following formula: Cost of container and lid (number oftimes a set is used per month) multiplied by the cost of wrap, tape andindicators minus the cost of the container filter and lock. The resulting numberis the number of months that it will take to pay back that initial investment.Many additional variables can be added, and of course you may wish to usedifferent measures than payback.

The only question remaining is: "Which container system should Ipurchase?"

Choosing a Vendor

There are a number of manufacturers in the container market, making forhealthy competition among issues of technology and cost control. However, if youdo your homework, you may find that some vendors stand out from the others.Consider these factors when choosing a container vendor:

  • Only work with a vendor that can produce FDA 510(k) Class II clearance.

  • Make sure their sterilization validations included very dense and difficult loads (worst case scenario) as well as difficult mechanical components (like motors).

  • Consider the vendor's reputation within the industry (tenure, quality and commitment).

Considering the above points should help you make a confident decisionregarding sterilization needs for your hospital. The future in sterilization isbright, and the innovation and production of visionary methods that surroundthis industry continues to advance the central service/sterile processingprofession.

Bryant C. Broder, CSPDT, ACSP, is manager of surgery processing at SaintMary's Mercy Medical Center in Grand Rapids, Mich. and president of the AmericanSociety for Healthcare Central Service Professionals (ASHCSP). The author wishesto thank John Cox and Jeff Smith from AESCULAP for providing information forthis article.