In this article, Karen Greene of DDL, Inc. and Stuart Long of Life Packaging Technology report on best practices and insights for the design and development of the medical device packaging system.
For manufacturers of terminally sterilized medical devices, compliance to the Intl. Organization for Standardization ISO 11607:2006-"Packaging for Terminally sterilized medical devices"-Part 1 and Part 2 is a requirement. A published tool to guide and assist you in compliance with ISO 11607 is the Assn. for the Advancement of Medical Instrumentation AAMI TIR 22. TIR 22 is a technical information report published by AAMI for compliance assistance. It is not a balloted standard but is reviewed by an AAMI technical committee. This article does not address Part 2, equipment and process validation.
Packaging Essential #1: Packaging design requirements
It is imperative to define the packaging system in order to produce a successful package design. The packaging engineer/designer must collaborate with project team members to create a packaging-design requirements document that provides a clear expectation of the function, limitations, special features, aesthetics, product/company branding, cost limitations, size limitations, sterilization method, labeling requirements, hospital/clinic storage requirements, case count, and possible adverse conditions of use and/or distribution and storage.
Do not limit your consultation to your marketing and product development representative. Valuable and detailed input can be obtained from the clinical team member, the end user, such as the clinical nurse, the O.R. technician, the Cath Lab technician, and the physician. Also, consult your field sales representative for insight into competitive products. Plan a trip to a local clinical site to see firsthand the environment in which your packaged device will be deployed. Prearrange a visit, and you will find a warm reception from the clinical staff, as people love to provide their opinions.
Packaging Essential #2: Packaging system hazard analysis
The goal of a thorough packaging system hazard analysis is to eliminate all high-severity hazards and reduce as many medium- and low-severity hazards as possible. Two prime high-severity hazards are breach of the sterile barrier (for a sterile barrier package) and damage to the medical device, which is not easily detectable and may impact the safe and effective use of the device. Annex A (medical devices) and Annex B (in vitro diagnostics) of ISO 14971 provide a set of questions to help illicit the identification of hazards. The package/device system can be reviewed by a number of analysis techniques, including top-down and bottom-up approaches. A typical bottom-up approach is an FMEA, or a failure modes and effects analysis. An FMEA facilitates focus on a specific component or element, e.g. a sterile barrier system. A typical top-down approach is an FTA, a fault tree analysis. You start with an undesired consequence, such as breach of the sterile barrier, and then identify the initiating and contributing events that must occur to produce it.
In summary, perform a packaging system hazard analysis early on after the package design requirements have been established and then move through the next few essential activities of defining the clinical storage, handling, and use environments as well as the distribution and handling environments so that you can begin the valuable activity of prototyping the packaging system design.
Packaging Essential #3: Evaluation of similar or competing devices
The value of evaluating similar or competing devices may appear to be obvious but is not rigorously put into practice. Identify your key competitors and/or comparable devices and get yourself out into the clinical setting to determine what your target customers love and hate about these packages. Inquire about every facet of the packaging design and ask your customers to prioritize their top three requirements for the package. Consider the following:
• Labeling for product identification, directions for use, bar coding, and inventory management requirements
• Examination of existing storage systems for integration
• Ease of use of package/device
• Package size as it relates to storage and use
• Packaging materials utilized (primary, secondary, and tertiary packaging systems)
• Is it imperative that the package is see-through and why?
• Does the primary sterile barrier package impede removal and aseptic technique?
• Does a coiled device present a significant hurdle to good clinical application because the device has taken an unacceptable "set"?
• Does the package facilitate one-handed opening and removal?
• If the device is a procedural kit, are all the expected and necessary components contained within the kit package?
You will not have the time or resources to gather a statistically significant data set on these package design considerations, but the value of a firsthand experience in the clinical setting, including a dialogue with the clinical staff on their input and the reasons for their opinions, will prove invaluable toward a successful package design. As a packaging design professional, you will be able to quickly discern what will or will not work based on firsthand clinical input.
Packaging Essential #4: Clinical application of the sterile medical device
In Packaging Essential #3, you researched how your packaging system would be stored and staged for use on your patients. In Packaging Essential #4, you gather information on the direct use of your sterile medical device on the patient and the specific role your packaging system plays in the safe and effective use of the medical device. An extremely valuable experience for the packaging designer is to witness a like or identical clinical procedure with the devices. You will experience firsthand how the technicians, nurses, and doctors access the pack and, if necessary, utilize the package design to successfully execute the procedure.
Packaging Essential #5: Distribution, storage, and handling of the medical device
Today's increasingly complex medical devices require the package designer to perform a thorough investigation of the anticipated distribution, storage, and handling conditions of their medical device. Clinical trial packages require focused attention, as frequently shipping, storage, and handling activities contain exceptions such as prolonged storage at temperature extremes at small clinical settings.
Devices are occasionally carried in luggage by members of the project team to the clinical site. Perhaps the device is temperature-sensitive and requires thermal insulation. What is the temperature profile of the seasonal shipping event as well as the device temperature and humidity stability range? For air shipments, do altitude and corresponding pressure differentials create a problem for maintenance of package integrity (seals)? Seek out and discuss these issues with project team members responsible for the execution of the clinical trial (as applicable) or your shipping and logistics team for a flowchart of the distribution channel of your medical device. At this stage in your project, you are now ready to prototype your package system design.
Packaging Essential #6: Prototype the packaging system
Medical device prototype packages can be used to evaluate the performance of the product/package prior to the commitment of the validation. Prototyping packages can incorporate multiple design options that will allow you the opportunity to evaluate the performance of different designs without going into production. Parallel path development of multiple design options will help prevent the dreaded "starting over at the beginning" if an unexpected packaging design flaw presents itself.
In order to develop a medical device packaging prototype, you must first understand the package design input requirements. These are the requirements to which the package must perform. Basic package design input requirements include new or redesigned packaging, product characteristics and hazards, device classification, sterilization method, shelf-life requirements, atmospheric hazards, aseptic transfer, materials, materials compatibility, visual appearance, mechanics, manufacturing processes, performance testing, and also sustainability. Brought together, the packaging prototype is an indispensable tool to be used to determine which design options will work, and which options will not.
When developing a medical device packaging prototype, there are two primary sources for your packaging prototype. One is the packaging design and prototyping firm. These firms specialize in designing packaging prototypes. Packaging design and prototyping firms offer an unbiased approach. This is advantageous in that you will not be obligated to a specific material combination, and the complete packaging system is developed by one source. Typically, costs from the packaging design and prototype firm is structured on an individual unit or low-quantity basis.
The other primary source for the medical device packaging prototype is the materials manufacturer. The materials manufacturer is an expert with their materials. The prototype will typically be to the exact specifications of the manufactured materials. The packaging material supplier is usually able to offer packaging prototypes at little or no cost, based on the stipulation that there is a degree of confidence in securing the production materials business.
Medical device packaging prototyping is a specialized and precise discipline. A package failure recognized at the validation stage is as unacceptable as a failure in the operating room. When done right, the medical device packaging prototype can make the difference between the success or failure of a medical device.
Packaging Essential #7: Package system performance testing
A design process is always iterative. After you sort and filter through the input on your package system prototype, modify your package system design such that these top three issues can be successfully addressed:
• Package can be effectively sterilized via the designated method (including materials sterilization compatibility).
• Package does not render the device useless or a risk to patient safety.
• Package/device can be assembled with a time standard (rough) acceptable to your manufacturing team.
You have now sourced sufficient input to develop a package system that you can run through package performance and seal integrity testing to refine your package system design for maintenance of sterile barrier integrity and to deliver a safe and effective medical device.
For a terminally sterilized medical device, you will be pursuing compliance to ISO 11607-1:2006. This article does not present an outline for compliance to this document, however, these activities support the compliance requirements specified with ISO 11607-1:2006.
For appropriate test methods to evaluate the performance of your packaging system prototype, reference Annex B within ISO 11607-1:2006.
It is important to secure actual medical devices or simulated devices to be included in this package performance testing. Inclusion of the medical device or simulated or like device will provide input toward determining the hazards of shipping and handling on the safety and efficacy of the device and device/package system. Assemble the device/package system and sterilize the test units with the production sterilization process. Consider challenging the packaging system in order to bring forth design weaknesses. Evaluate and correct the design as necessary (see Suggested test methods sidebar, below).
Analysis of test results
You have now executed a feasibility test, package system performance test, or a notebook study. The test results from the package integrity tests, seal strength, and device evaluation and performance will support the completion of the risk assessment portion of the risk management process. Findings such as physical breaches to the sterile barrier materials (films, pouches, trays), compromised seal integrity (open seals, channels) and damaged or compromised medical devices will require a package system design modification to eliminate the failures as well as possible modification to the medical device to eliminate the package failures and/or device failures. Package performance testing will be repeated with the modified package system to evaluate the improvements.
Following these seven packaging essentials effectively and efficiently supports the required compliance to ISO 14971:2000 & 14971/A1:2003 "Application of Risk Management to Medical Devices" with regard to executing a risk assessment and provides valuable input toward compliance to ISO 11607-1:2006 relative to package sterile barrier integrity and medical device functionality through the hazards of handling, distribution, and storage. The competitive advantage for the medical device manufacturer of executing these suggested seven essentials is a successful medical package design.
Conclusions
• Engage early in the medical device development process.
• Gather package design input from multiple relevant sources.
• Prototype your package system design.
• Performance-test your prototype package design (with device or simulated device).
• Evaluate package integrity and medical device performance.
• Iterate as required to eliminate high-severity hazards and minimize medium to low hazard.
Suggested test methods
• Conditioning of packaging materials, packages: American Society for Testing and Materials ASTM D4332:2001.
• Performance testing: ASTM D4169:2005 Practice for performance testing of shipping containers, ISTA 1, 2, 3 Series International Safe Transit Assn. Preshipment Test Procedures.
• Package Integrity (porous packages): ASTM F1929:1998 Standard test method for detecting seal leaks in porous medical packaging by dye penetration.
• Package Integrity (internal pressurization): ASTM F2096:2004 Standard test method for detecting gross leaks in porous medical packaging by internal pressurization (bubble test).
• Seal Strength: ASTM F88:07a Standard test method for seal strength of flexible barrier materials.
• Visual Inspection: ASTM F1886-98 Standard test method for determining integrity of seals for medical packaging by visual inspection.
• Medical device evaluation: Return the devices to your product development partner for their evaluation and input.
Editor's Note: Karen K. Greene, CPP, is the technical director for DDL, Inc., a third-party testing organization specializing in package, product, and material validation testing for the life sciences industries, including medical device, pharmaceutical, biopharmaceutical, and biotechnology. Stuart Long is principal of Life Packaging Technology, dedicated to unbiased packaging engineering solutions within the life sciences, medical device, pharmaceutical, biotechnology, electronics, and consumer products sectors.
