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Articles from 2002 In September


State of the Art

Originally Published MPMN September 2002

REGIONAL FOCUS

State of the Art

Introducing an occasional series reporting on regions with a tradition of medical device manufacturing. First stop: Minnesota's Medical Alley.

Norbert Sparrow


(click to enlarge)

More than 800 registered device firms are located along a 300-mile corridor in Minnesota that stretches from Rochester in the south, through Minneapolis and St. Paul, to the north of the state. Known as Medical Alley, the region is the largest producer per capita of medical equipment in the United States. This concentration of industry has spawned a vast network of suppliers uniquely attuned to the needs of device OEMs. In this occasional series devoted to our nation's centers of medical technology, MPMN reports on how and why the device industry took root in the region, and the way in which area suppliers are helping it to meet current and future challenges.

A Med-Tech Mind Set

In the beginning, there was Medtronic . . . or maybe not. Conventional wisdom and a cursory overview of the history of the device industry in Minnesota suggest that the medical device powerhouse laid the groundwork for Medical Alley. But although Medtronic played a pivotal role in the regional emergence of the medical device sector, a number of other factors should not be overlooked, say local industry experts.

The internationally renowned Mayo Clinic in Rochester instilled in the populace a med-tech mind set early in the last century. "Physicians from the Mayo Clinic, as well as staff from the University of Minnesota, collaborated with engineers and entrepreneurs," says Don Gerhardt, president and CEO of Medical Alley, a trade association that represents more than 250 member organizations involved in healthcare activities. The current industrial landscape of the region was shaped by "those two organizations' inventiveness and drive for quality," says Gerhardt, "which was ultimately transferred to the adventuresome side of entrepreneurship."

The presence of information technology companies during that industry's early days also had an effect, according to Gary Tapp, a senior partner at outsourcing firm MedTech Development. "Medical tends to follow high tech," says Tapp, "and Minnesota was a high-tech community for a long time. In many ways, it still is."

To understand why the device industry flourished here, says Dale Olseth, CEO of the surface-treatment technology firm Surmodics and former CEO of Medtronic, one must take into account the character and values of Minnesotans. "This part of the world has its roots in the cultures of northern Europe, which have always had a strong work ethic," says Olseth. "We square the corners. There are no fast bucks here," he adds, citing 3M as a prime example. (The company is currently celebrating the centennial of its founding as the Minnesota Mining and Manufacturing Company in Two Harbors.)

"3M has never been what I would call a sexy company, but it squares the corners—it does things right. It has always looked after its people," says Olseth. "That has spawned a culture that works well with healthcare, where you want quality products and organizations." Medtronic was a beneficiary of this culture, and has helped to perpetuate it. Few know the company's history better than Olseth, who managed Medtronic's finances in the early 1960s, eventually taking it public, and served as CEO from 1976 to 1986. It's an experience he recalls fondly.

Earl Bakken, an electrical engineer who founded Medtronic as a medical equipment repair company in 1949 with partner Palmer Hermundslie, was a visionary, says Olseth. "The people at Medtronic were do-gooders, and I mean that in the best sense," Olseth says. "We wanted to do good." That ethos came directly from Bakken, he adds. "I used to have to balance his checkbook," says Olseth. "He just wasn't able to deal with it. His mind was on bigger things."

Bakken and Hermundslie initially set up shop in a 600-sq-ft Minneapolis garage. In one month during its first year, the company grossed $8 for the repair of a centrifuge.

Realizing that they had to diversify if they wanted to survive, the partners began representing medical equipment manufacturers in the upper Midwest. As they made their rounds, they became acquainted with medical practitioners and researchers throughout the area, who began asking Medtronic engineers to modify existing equipment and build custom devices for special tests.

An encounter with C. Walton Lillehei, MD, a pioneer in open-heart surgery at the University of Minnesota's medical school, proved to be a seminal event in the company's history. Bulky ac-operated pacemakers were the norm in the mid-1950s, and Lillehei and his colleagues teamed up with Medtonic engineers to develop a better system. Bakken created a wearable, external-battery-powered device that revolutionized medical technology. Many more innovations followed, and today the firm is a $6.5 billion medical technology multinational.

An Abundance of Suppliers

Precision coils and assemblies that are integrated into a range of medical devices, primarily to strengthen catheters, are supplied by St. Paul–based Vadnais Technologies.

The presence of Medtronic, St. Jude, Guidant, and several hundred other innovative device OEMs has fostered the development of a pool of suppliers offering an array of services. Many have developed a technological skill set and in-depth understanding of regulatory requirements that have made them players in the global supply chain.

The reputation of the region is such that Ireland-based Creganna Medical Devices, a supplier of metal and plastic components and subassemblies, opened its North American sales office in the Minneapolis area. Citing the concentration of medical device companies, the region's tradition of manufacturing acumen, and its central location, "Minneapolis is excellent in every respect," says president of sales and marketing Eoin O'Madagain.

When MedSource Technologies was incorporated in 1998 and embarked on a series of acquisitions to build a comprehensive outsourcing company catering to the device industry, it chose Minnetonka as its headquarters. For a company promoting the outsourcing model to device OEMs, it made eminent sense to set up shop in the device industry's heartland. The strategy has been a tremendous success, says Steve Mogensen, director of sales operations.

"Historically, the device industry has been vertically integrated," says Mogensen. "People were not willing to give up final control of a finished device, especially a Class III device." But the sector has undergone substantial change in the past few years, he adds. "Many larger companies have figured out that they're really good at R&D activities and sales and marketing, but that it doesn't make a lot of sense to spend capital on a building and machinery, and to hire a bunch of people to manufacture widgets. That is not their core competency," Mogensen explains.

MedSource has integrated an array of expertise and manufacturing capabilities so that OEMs can channel resources on their key activities. The company's services span development and design, prototyping, manufacturing, assembly, packaging and sterilization, and distribution.

Golden Valley–based MedTech Development is also an advocate of the outsourcing model, but it took a slightly different tack than MedSource.

"The company began about 11 years ago as a medical device project management company," says senior partner Gary Tapp. "Our job was to go to companies and educate them about quality project management." Eventually the firm began taking over projects that were not part of their customers' mainstream product lines. "We took that concept and put more of a structure around it," says Tapp, thereby evolving into a "group of companies, each a leader in its field, under one roof."

The company's philosophy, says director of business development Ron Schlenker, is to take the strategic sourcing mentality and orient it toward product development. "We implement the management philosophy and process, from intellectual property and contract manufacturing to distribution, across different organizations," says Schlenker. The organization comprises more than 25 CRO consultants, 135 engineers, and 110 manufacturing professionals, and it has contributed to the development of numerous medical products, including more than 80 types of stents and delivery systems.

These companies and more than a dozen other area suppliers are profiled in the following pages of this Regional Focus section (hundreds more can be found in our on-line suppliers directory at www.devicelink.com). Regardless of the product or service that you are sourcing, you will almost certainly find a company in Medical Alley with the expertise and capabilities to meet your requirements.

Copyright ©2002 Medical Product Manufacturing News

Validation Software Speeds Up Packaging Process

Originally Published MPMN September 2002

EQUIPMENT NEWS: Packaging and Assembly Equipment

Validation Software Speeds Up Packaging Process

Enhancements can shorten production times and increase safety

Susan Wallace

In order to assist manufacturers in complying with the ISO 11607 standard requirements for packaging process development, equipment manufacturers are increasingly incorporating validation software and equipment into their machines. Rod Jennings of Van der Stahl Scientific Inc. says that his company's new pouch sealer "will incorporate real-time seal-integrity monitoring to enhance validation compliance."

Enhancements to validation services can also "ensure the efficient and safe operation of our packaging solutions in the medical industry," says Michel Defenbau, president and CEO of Multivac Inc.

This article looks at various validation additions to packaging machinery and also at equipment designed to speed up the packaging process.

Enhancement Package for Validation Services

A three-part Multivac Inc. validation service for its RS30 rollstock medical device packaging system surpasses FDA guidelines and includes a factory documentation package, multiple machine features, and installation qualification.

"This enhancement service allows customers to significantly shorten time to productivity by ensuring problem-free validation of the installation, operational parameters, and packaging process," says company president Defenbau.

The R530 features measurement and control redundancy. Control monitors with independent redundant sensors enable a backup warning system to alert operators of potential problems that can affect system uptime.

Prior to shipping, each machine undergoes a documented factory checkout, ensuring that the customer receives specified features, capabilities, and sequence of operations. Documentation includes a software validation certificate, factory acceptance testing documentation, calibration certification of the instruments used in manufacturing, and certificates of accuracy for all sensors used on the machine.

Medical Pouch Sealer

The MS-350 pouch sealer from Van der Stahl Scientific Inc. checks all key set-point constituents.

A pouch sealer checks all key set-point constituents for good scientific validation. The Model MS-350 from Van der Stahl Scientific Inc. monitors temperature at the heat platen to ensure that temperature tolerances are within the set-point range. The unit does not rely on air pressure, and can deliver constant repeatable pressure with a robust electronic solenoid, despite possible fluctuations in the facility's system.

A menu-driven Hitachi microprocessor ensures that dynamic pressure is applied to each pouch and constantly monitors the servo's pressure at the seal bar. The unit can also be set to an autocycle mode, which allows the machine to be set in tenth-of-a-second increments up to 5 seconds for automatic cycling.

Because the sealer does not use a pneumatic-driven pressure bar, no air is required, just a 110-V receptacle. The machine features a 10-mm seal width, and is 350 mm long.

Pouch-Opening Machine

The QuickPouchMicro from Quickpouch holds a pouch open while it is being filled.

A pouch-handling machine can speed up pouch opening by a factor of two or more, according to Quickpouch The QuickPouchMicro is designed to reduce handling of the pouch by holding the pouch open while it is filled, enabling the operator to have both hands free. This can decrease operator fatigue, which can lead to carpal tunnel syndrome and other repetitive-stress injuries.

The pouch opener features intuitive adjustments for different-sized pouches, a foot pedal for operator triggering, an auto mode that will cycle the machine at a set speed, and built-in resettable counters. The unit's footprint is less than 12 in. wide by 18 in. long, and it weighs less than 25 lb. The base model opens pouches from 2.5 to 6 in. wide, and 4 to 8 in. tall.

Four-Side-Seal Packaging Machine

The 4SS Model 400 from Doyen Medipharm Inc. doubles the speed of the company's previous model.

A rotary side-seal packaging machine runs at 50 m/min and can produce more than 400 packs per minute. The 4SS Model 400 from Doyen Medipharm Inc. will package medical devices such as wound-care dressings, diagnostic devices, drapes, catheters, and sutures, and can also be used to produce three-side self-seal bags for hand packaging of devices. The maximum package size is 330 mm wide and 500 mm long.

The 4SS model doubles the speed of the previous model, according to the company. The increase in speed was achieved by improving the sealing characteristics through a combination of processes, including adding multiple sealing units and the company's pressure control system. The machine provides product changeover in less than 10 minutes and can store up to 50 package designs in the product memory.

The unit is supplied with complete installation qualification and operational qualification documentation, and is compliant with all QSR, OSHA, and CE requirements.

Medical Device Bagger

A machine is designed for fully automated packaging, beginning with a kit or a specified device entering the machine through a right-angle infeed conveyor. Once the product enters the filling station, the individual bag-opening section of the Medi-Bagger from Optima Machinery Corp. works to position the bag opening for product insertion. This is accomplished with a servo-controlled bag infeed conveyor and a vacuum system for accurate bag positioning.

The machine comes equipped with features including an infeed pusher and manually adjustable bag grippers and clamps. To assist in the sealing portion of the process, the unit incorporates a controlled sealing drive and a monitoring system. A hot-wire weld will generate a seal that can be validated by recording the correct values for time, temperature, and pressure.

Automatic Assembly Solutions

The Flexcell-S from Mikron Technology incorporates its own conveyor belt to control the individual cells.

A multipurpose system incorporates its own conveyor belt for independent commissioning of individual cells. The Flexcell-S from Mikron Assembly Technology measures 3 m in overall length and provides optimum flexibility during line reconfiguration. Each cell is autonomous, fitted with industrial PC control and built-in high-performance monitoring.

A numerically controlled indexing system is used for pallet flow control during assembly, processing, or special testing. Low-cost changeover of the pallet configuration is achieved by means of minimizing the customer-specific part of the pallets and retaining all the tooling in the cell.

Base configurations incorporate palletization and depalletization units, cam or NC pick-and-place units, testing units, and inspection stations.

The design of the cells and the use of permanently lubricated elements ensures ease of maintenance and conformity with the production requirements of a Class 10,000 cleanroom. The Flexcell can also be equipped with a laminar-flow unit that introduces clean, superfiltered air directly above the fixture pallets for use in cleanrooms exceeding Class 10,000.

Assembly Machines

A spring-loaded device assembly system from Kahle Engineering Corp. can process from 60 to 360 parts per minute.

A completely integrated spring-loaded safety device assembly system provides spring coiling, component assembly, 100% inspection and testing, a boxing system, and complete lot traceability. The system from Kahle Engineering Corp. can process from 60 to 360 parts per minute.

Each spring-coiling machine is linked directly to a nest assembly position of the assembly machine. If one of the spring coilers fails, the assembly machine automatically stops component loading and assembly operations on that individual nest position, while production in all other nest positions continues. When the spring-coiling machine comes back on-line, the nest position assembly is restarted, thus minimizing component waste and unnecessary machine operations.

The system is designed with modular cam stations that enable the machine to cycle down to slower speeds to perform complex sampling inspections without product waste or assembly error.

Copyright ©2002 Medical Product Manufacturing News

Spotlight on Filtration Products

Originally Published MPMN September 2002

SPOTLIGHT

Spotlight on Filtration Products

Capillary-pore membranes

Capillary-pore membranes are made of polyester and are characterized by a defined pore diameter usually ranging from 0.1 to 10.0 µm and a defined pore density ranging between 105 to 109 pores per square centimeter. Multiple pores visible at the surface divide further into individual pore channels inside the RoTrac membranes, guaranteeing that all pores have the same diameter. Hydrophilic surface, hydrophobic surface, supported and reinforced, and black membrane variations are offered. Oxyphen AG, Gubelstr. 11, P.O. Box 4614, Zug 6304, Switzerland.


EMI filters

Ceramic chip components combine capacitor and inductor elements in a single distributed constant-circuit filter. The W2F-series surface-mountable chip filters provide low parallel inductance and offer decoupling capabilities for all high-di/dt environments while providing significant noise reduction in digital circuits up to nearly 5 GHz, according to the company. The units are rated at 100 V and 300 mA with capacitance ratings ranging from 22 to 47,000 pF. Current-carrying capabilities range from 330 mA to 1 A. Standard operating temperatures range from -55° to 125°C. AVX Corp., 801 17th Ave. S., P.O. Box 867, Myrtle Beach, SC 29578.


Air filters

Air filters are designed specifically for use with cooling systems in universal power supplies and power-generation enclosures. The Quadrafoam open-cell polyurethane material is treated with a thin layer of flame-retardant coating, resulting in a flexible and resilient product that is effective in power applications for deployment in harsh environments and high-temperature and high-humidity conditions. The foam contains an antimicrobial additive with a fungus growth rating of zero. Filter assemblies are available in a wide range of pore sizes. Universal Air Filter Co., 1624 Sauget Industrial Pkwy., Sauget, IL 62206.


Transfer and filter devices

Transfer and filter devices are available for a variety of fluid-transfer applications. The company's product line includes the Mini-Spike dispensing pin for preparing and dispensing diluent or additive from multidose rubber-stoppered vials and the Micro Chemo pin with 0.2-µm hydrophobic air-venting filter that prevents exposure to toxic fumes during drug reconstitution. Other products such as filter needles, vented needles, double-ended transfer needles, air-venting filters, hydrophilic in-line cone filters, and filter hubs in many configurations are also offered. Burron OEM Div., B. Braun Medical Inc., 824 Twelfth Ave., Bethlehem, PA 18108.


HEPA/ULPA filters

Compact, curved arc-shaped air filters provide a wall-to-wall clean-air shower that flows uniformly to exhaust grilles, carrying out contaminants generated in the room. Applications for the Vector air filters are hospital and outpatient surgery rooms, patient isolation rooms, laser treatment rooms, tissue culture laboratories, burn treatment rooms, and tuberculosis negative air isolation rooms. The units measure 24 in. wide and 24 in. high, with a 2.5-in. minipleat filter media. Glass media are 99.99% efficient at 0.3 µm, and PTFE media are 99.99995% efficient at 0.1 µm. Bio-Safe America, Sterilaire Medical Div., 3250 S. Susan St., Santa Ana, CA 92704.


Synthetic fabrics

Precision-woven synthetic fabrics are suitable for filtering blood in arterial, cardiotomy, and transfusion devices. SaatiCare fabrics are also used for drug-infusion systems, flow control devices, moisture barriers, and biopsy bags, and for EMI and RFI shielding. A narrow aperture-size distribution ensures accurate and predictable filtration, and the company's proprietary finishing system is compliant with USP Class VI. Fabrics are available custom manufactured into slit rolls, stamped parts, tubes, pleated elements, and bags. SaatiTech Inc., 247 Rte. 100, P.O. Box 543, Somers, NY 10589.


Filtration equipment

A wide variety of technologies are available from a representative for numerous filter manufacturers. Products are suitable for use as prefilters and for parenteral fluid filtration. Offerings include pleated-style membrane filters, hollow-fiber cartridges capable of reducing endotoxin levels in fluids, bag filters and housings, and sanitary and industrial-style filter housings of all sizes that incorporate one or more elements. Advanced Filtration Co., P.O. Box 324, Howell, NJ 07731.

Copyright ©2002 Medical Product Manufacturing News

Advances in Adhesive Products

Originally Published MPMN September 2002

PRODUCT UPDATE

Advances in Adhesive Products

Epoxies and equipment offer increased functionality

Zachary Turke

Adhesives are an integrated part of many medical devices. Transcending their traditional role of simply holding components in place, however, these products now offer manufacturers sterilizability, chemical resistance, electrical insulation characteristics, and a range of other properties that can increase device functionality. But with what seems like an almost unlimited number of different epoxy formulations on the market, it can be difficult to determine which one will work best with a specific product.

To help alleviate this dilemma, this article examines several recent advances in adhesives and related equipment. The accompanying Buyers Guide grid beginning on page 60 provides a comprehensive list of these and other companies that supply such products.

Semirigid epoxy accommodates varying rates of thermal expansion

Supplied by Master Bond Inc., an epoxy allows the bonding of components with different rates of thermal expansion.

Suited for the assembly of disposable and reusable devices, a two-component epoxy resin system from Master Bond Inc. cures semirigidly to allow the bonding of elements with different rates of thermal expansion. "Many devices are required to undergo thermal cycling, something that can put stress on the components used to hold them together," explains vice president of technical support Robert Michaels. "Our EP21LV adhesive cures with a combination of flexible and rigid properties to eliminate this concern. It isn't rubbery like silicone, but it has some give, and simultaneously offers toughness and durability," he says. Providing bond strengths of 500 to 5000 psi, the epoxy is compatible with most metal, plastic, glass, ceramic, and rubber substrates.

Certified to USP Class VI specifications, EP21LV epoxy does not contain solvents or other volatile ingredients. Applied by manual or semi- or fully automated methods, the material offers limited sterilization capabilities. "Under most conditions, it will withstand three to five sterilizations by gamma, EtO, chemical, or autoclave methods, though in certain situations it could last for up to 10 cycles," says Michaels. According to Master Bond, the epoxy cures readily at ambient temperatures, or more quickly when heat is applied. When fully cured, the polymer offers resistance to vibration, impact, thermal shock, and chemicals. Acceptable operating temperatures span –80° to 250°F.

The EP21LV adhesive is suited for bonding, sealing, and casting applications. Commonly used with endoscopes and diagnostic equipment, the material can also be used for potting and encapsulation. Because it withstands brief exposure to harsh acids and bases, and offers electrical insulation properties, the epoxy is compatible with adverse environmental conditions.

Low-fluorescence adhesive enhances signal detection

Developed by Adhesives Research Inc., an adhesive system exhibits low autofluorescence to enhance signal detection in molecular technology applications. Used for bonding cover films to biological assays, the pressure-sensitive adhesive reduces the risk of undesirable background interference. "The precise evaluation of fluorescence levels is essential for analyzing biomolecules, drug discovery, DNA sequencing, and a range of other applications," says director of marketing William Meathrel. "This adhesive ensures that researchers will be able to perform these tasks without worrying that background fluorescence is affecting sensitivity."

Other beneficial properties of the adhesive include dimensional stability and the ability to withstand temperature and moisture changes. According to company sources, the material does not flow into microfluidic channels, and adheres to surfaces without creating voids or gaps that would allow the migration of assay components. Available in flexible or rigid formulations, the clear adhesive is resistant to chemical reagents and offers compatibility with electrophoretic and other means of separation.

Potential applications for the adhesive include multiwell platforms, microarrays, microfluidic devices, and biocards. To ensure a good fit with an application, the company can modify the adhesive to offer hydrophilicity and other properties.

Dispense valve minimizes dead space to increase deposit control

A needle valve is constructed with a minimum of dead space to allow the application of adhesives in deposits as small as 0.007 in. in diameter. Unlike traditional products, the 741 MD-SS MicroDot valve from EFD Inc. features an internal needle that is seated in the hub of the dispensing tip rather than the valve body. "This construction eliminates the need for a tip adapter, minimizing dead space to within the cannula itself," says technical director Bob Tourigny. "As a result, the MicroDot valve gives manufacturers the ability to set deposit amounts very precisely and maintain that volume over time."

Another feature of the valve is a two-ring calibration knob that eases the task of needle replacement. "When changing needles, the important thing for consistency is to maintain the same stroke and tip-to-substrate distance, tasks that are complicated by the inevitable tolerance variations between components," says Tourigny. "Our valve makes it easy to restore the same settings by simply turning the knob until you're back where you need to be." Tourigny estimates that the calibration knob shortens needle replacement time to 30 seconds from 4 to 5 minutes.

The compact, pneumatically operated valve is compatible with most assembly fluids, including UV-cured adhesives, solvents, lubricants, and adhesives. The product can be used with automated equipment, robots, x-y-z machinery, and workbench or stand-mounted dispensing stations. Common medical applications include the assembly of disposable plastic products, microelectronics, and fiber-optic devices. Typically, the component is used in conjunction with the company's Valvemate 7000 controller, which allows the adjustment of dispense times in increments of 1/1000th of a second.

UV-cured adhesives feature USP Class VI certification

A UV-cured adhesive from Tangent Industries Inc. is free of solvents and nontoxic when fully cured.

Available in a variety of formulations, UV-cured acrylate adhesives from Tangent Industries Inc. are certified to USP Class VI and ISO 10933 specifications. Capable of bonding glass, stainless steel, and polycarbonate and other plastics, the Vitralit series of adhesives are free of solvents and nontoxic when fully cured. Suited for filling cracks and encapsulation, the materials cure readily when exposed to UV light. "Typical curing times range from 1 to 2 seconds to a couple of minutes, depending on the nature of the assembly and the thickness of the adhesive," says vice president Richard Wick.

Compatible with manual to fully automated application processes, the Vitralit adhesives withstand limited gamma, EtO, and vapor sterilization. Common product uses span the bonding of anesthesia masks, blood pressure transducers, blood oxygenators, stopcocks, fittings, adapters, and arterial filters. Other applications include the joining of stainless-steel cannulae to flexible PVC infusion lines or transparent or translucent hubs and syringes. Though the product line includes a number of formulations, the company will custom design an adhesive to suit individual specifications upon request.

Copyright ©2002 Medical Product Manufacturing News

One-Way Valve Improves Venting Control During Surgery

Originally Published MPMN September 2002

PROFILE

One-Way Valve Improves Venting Control During Surgery

An adjustment knob maintains the proper amount of negative pressure

Norbert Sparrow

An adjustable one-way vent valve developed by 3-T and Geneva Medical Products prevents the accumulation of high blow-off pressure.
(click to enlarge)

One-way vent valves play a crucial role during open-heart surgery by redirecting blood from the heart to a heart-lung machine. The duckbill valve must prevent reverse flow and airflow back to the heart, which could cause an embolism. Chet Czaplicka, a partner at medical device OEM 3-T (Dearborn, MI), identified flaws in the design of existing valves during his years spent as a perfusionist. He vowed to build a better valve at 3-T and enlisted the help of Geneva Medical Products (Walworth, WI; www.genevamedical.com), a supplier of thermoplastic medical products, to develop a safer, more-efficient one-way vent valve.

Czaplicka lists three primary concerns in traditional vent-valve designs: an unreliable mechanism to control negative pressure, the presence of high blow-off pressure, and inefficiencies in the prevention of canula occlusion.

To improve control over the fluid and airflow entering the valve, an adjustment knob has been incorporated into the 3-T valve. When the knob is screwed shut, the venting function of the valve is at its minimum, thus maximizing fluid flow. The ratio is slowly reversed as the knob is turned. Flow control in many other valves of this type is typically a function of the user placing his or her thumb over the air vent. This method is less reliable than turning a knob, explains Czaplicka, and it requires considerable dexterity to modulate the flow.

The adjustment knob serves a secondary function in the prevention of cannula obstruction. Surgery can be interrupted when the drainage cannula comes into contact with the wall of the heart or aorta and becomes occluded. To resume drainage, the surgeon must interrupt the operation and reposition the cannula. With the 3-T valve, the perfusionist simply pushes the adjustment button to free the cannula, allowing the surgeon to concentrate on the task at hand.

Controlled Venting

Other valve designs may also foster a buildup of positive pressure between the valve outlet and the pump. "One-way vent valves must vent, or blow off, positive pressure," says Czaplicka. "If it is excessive, it can collapse the valve, allowing reverse airflow to the heart." To remedy this problem, the 3-T device has an umbrella valve beneath the duckbill valve. This design maintains a blow-off pressure two to three times lower than competitive products, according to the firm.

Czaplicka chose Geneva Medical Products as a partner in the project because of its expertise in the design, development, and manufacture of valves. The company has more than 30 years of experience in the manufacture of medical thermoplastic components and assemblies.

In addition to design assistance, the firm provided the tooling and prototyping, manufacturing, and validation services. To accelerate the development process and minimize tooling modifications, Geneva Medical Products used 3-D modeling and Gantt charts to keep the project on track. The company also ran a battery of tests on the product, including open inflow vacuum differential, occluded inflow vacuum relief, flow-rate and vacuum-level variation, and retrograde flow testing.

The 3-T valve is constructed of a clear plastic that allows the surgeon and perfusion personnel to view its status at all times. The material meets USP Class VI requirements.

3-T was founded in 1995 and provides medical tubing guides, suture guides, vein graft cannulae, myocardial temperature probes, and vent valves. The firm continues to collaborate with Geneva Medical Products to enhance its product line. Current projects include a blood reservoir for autotransfusion and a blood filter for person-to-person transfusion.

Copyright ©2002 Medical Product Manufacturing News

Plastic Alloy Enhances Image Clarity

Originally Published MPMN September 2002

PROFILE

Plastic Alloy Enhances Image Clarity

Material reduces interference in MRI applications

Zachary Turke

Thermoformed from the Kydex alloy supplied by Kleerdex Co., this phased-array neurovascular coil used with high-power MRI equipment does not cause interference.

For more than 10 years, Medrad Inc. (Pittsburgh) has produced fixtures and receiving coils for magnetic resonance imaging (MRI) equipment. Thermoformed from acrylonitrile butadiene styrene (ABS), these components record the energy emitted by hydrogen atoms in the body in the presence of a strong magnetic field. But when test data revealed that the ABS coils caused interference when used with newer, more-powerful MRI machines, the company realized it was time to find a new plastic material and turned to Kleerdex Co. (Aiken, SC).

"ABS was a fine material to use when MRI machines were long, narrow tunnels," explains Kleerdex marketing representative Richard Rapp. "But as designers have made these machines more open to allay patient anxiety, they have increased their magnetic power correspondingly to retain image clarity and accuracy. This causes problems for the plastic," he says. Like the human body, ABS contains loosely bound hydrogen molecules that are excited by the presence of the large magnetic fields produced by newer machines, resulting in the interference noted by Medrad. Kleerdex identified this shortcoming and suggested its Kydex alloy as an alternative material.

Made of acrylic and PVC, Kydex has more tightly bound hydrogen molecules than ABS. Medrad tried the alloy in some test coils and found that the material successfully reduced interference below detectable levels.

Clearer imaging is not the only benefit offered by Kydex. "MRI machines are typically placed in the center of high-traffic rooms, subjecting them to a lot of bumping, impacts, and repeated-use strain," says Rapp. The material helps to offset this wear and tear by offering an impact resistance of 18 lb∙ft, roughly double that of ABS. Certified as fire retardant to UL 94V-0 and V-5 standards, the material features a tensile elongation of 5800 psi, a modulus of elasticity of 347,000 psi, and a Rockwell hardness of 106. "Also, Kydex is cost competitive with flame-retardant ABS, and exhibits a broad chemical resistance. It also withstands repeated cleaning with strong cleansers without staining or fading," adds Rapp.

The Kydex alloy is compatible with a wide variety of manufacturing processes, including injection molding and vacuum, pressure, and thermoforming. Acceptable secondary processes for the material include sawing, filing, taping, gluing, and general machining. According to Rapp, Medrad was so pleased with these and other features of the material that they have made it the de facto standard for all their new parts. Rapp also sees applications for the material beyond MRI equipment. "Essentially, it's suitable for any medical instrumentation application where flame retardancy, high impact resistance, formability, and cleanability are important design criteria," he says.

Copyright ©2002 Medical Product Manufacturing News

My Favorite Bookmarks

Originally Published MPMN September 2002

E-NEWS

My Favorite Bookmarks

David Rivera
R&D Engineering Specialist
Allegiance, a Cardinal Health Co.

Zachary Turke

David Rivera

American Association for Respiratory Care (www.aarc.org) is a comprehensive one-stop source for information relating to respiratory care. We produce a variety of related products, including medication nebulizers, breathing circuits, and oxygen-therapy devices, and the site is helpful for understanding the day-to-day concerns faced by our customers. Covering a variety of pertinent topics, the page is host to a variety of studies, abstracts, and news articles.

American College of Chest Physicians (www.chestnet.org) contains clinical and technical information relating to cardiopulmonary medicine. The site's best feature is its exhaustive search function that allows you to pull up a list of relevant abstracts using a single keyword. In most cases, this search is more than sufficient to provide the information I'm looking for, but when it isn't, there is also a handy list of hyperlinks to other Internet sites that can serve as resources.

OnlineConversion.com (www.onlineconversion.com) is where I go when I need to convert something. The page contains more than 5000 units and 30,000 conversions, so I've always been able to find the equation I needed. And while this site is certainly functional, it also has its humorous side. Click under the Fun Stuff heading, and convert your age to dog years, find out how many days until your retirement, or even pick lottery numbers.

IHS Health Group (www.ihshealthgroup.com) supplies unbiased market information on the domestic and international healthcare industry. With reports available for download in a pdf format complete with charts and graphs, the site helps to identify growth markets and keep tabs on industry trends and developing technologies. The page also contains a regulatory section that can serve as a supplement to FDA resources.

Allegiance, a Cardinal Health Co. (McGaw Park, IL; www.allegiance.net) supplies surgical instruments, procedure packs, oxygen masks, intravenous solutions, patient-care supplies, diagnostic instrumentation, and other products worldwide. The company also offers contract services spanning clinical and productivity consulting, supply packaging, and just-in-time delivery.

Copyright ©2002 Medical Product Manufacturing News

Steven Label Offers On-Line Order Tracking

Originally Published MPMN September 2002

E-NEWS

Steven Label Offers On-Line Order Tracking

Zachary Turke

www.stevenlabel.com.
(click to enlarge)

A label manufacturer has added on-line order-tracking capabilities to its Web site to facilitate supply-chain management among its customers. Dubbed the Stat system, the tracking service from Steven Label (Santa Fe Springs, CA) can be found at www.stevenlabel.com and gives OEMs greater control over the ordering process by providing more information. "Users just log on to the page, and they can proof their labels as pdf documents, see where their order is in our plant, and find out when it is due to ship," says president Steve Stong. The Stat system also allows companies to access complete order histories, and contains courier service links that enable product tracking during shipment.

According to company sources, the tracking system helps to ensure that OEMs receive the components they need at the appropriate times and in the required quantities. "To successfully produce a medical device, manufacturers need to bring a lot of different parts together at the same time and this site helps them achieve this goal," explains Stong. "It allows users to see exactly what they're getting and when, something that's particularly useful in situations where the purchaser and recipient are not at the same location," he says. Because it allows users to view a complete order history with price figures, the service could also help to reduce costs by optimizing ordering patterns.

Steven Label produces instruction labels and cards, polycarbonate overlays, Tyvek lidding, die-cut foam parts, membrane switches, spacers, and insulators. Common product applications include infusion pumps and medical electronics.

Copyright ©2002 Medical Product Manufacturing News

Web Conversion Tools Simplify Tape Specification

Originally Published MPMN September 2002

E-NEWS

Web Conversion Tools Simplify Tape Specification

Zachary Turke

www.adchem.com
(click to enlarge)

Hosted at www.adchem.com by Adchem Corp. (Riverhead, NY), an on-line conversion tool kit automatically calculates conversions unique to the tape industry to simplify product ordering. Featuring equations for roll length, area, thickness, weight, force, pricing, and other factors, the time-saving tool kit was designed with nonengineers in mind. "We specifically made the site simple to use so everyone could benefit from this tool," explains business development manager Walt Polifka. "Just enter one or two variables, hit the calculate button, and it does the rest," he says. Among other tasks, the kit can be used to determine required tape quantities and to ensure the size compatibility of tape spools with OEM process machinery.

Adchem supplies a variety of adhesive tape systems, including films, tissues, foams, fabric and double-coated papers; transfer tapes; one-side-coated products; and specialty materials. The tapes are available with solid adhesives or solvent acrylic and rubber adhesives. Sample product applications include sterilization bags and surgical drapes.

Copyright ©2002 Medical Product Manufacturing News

Device Tests Curved and Straight Needles

Originally Published MPMN September

HOTLINE

Device Tests Curved and Straight Needles

Both penetration and bend testing can be accomplished

A needle tester can measure the performance of both curved and straight needles. Traditionally, the test of needle sharpness is the measurement of the force required for it to penetrate a consistent membrane. Curved needles have been difficult to analyze because side loading is eliminated, which can skew the measurement of force. Read more...

 

Cutting-Edge Technology Yields Sharper Blades

Ion-beam milling produces ultrafine surgical instruments

Combining MEMS micromachining with high-energy physics, a process uses focused-ion-beam milling to produce cutting edges that are sharper than those obtained by previous methods. "Your average razor blade has a 600–1000-Å radius of curvature," explains Martin Newman, a principal with MDW Technologies (Newport Beach, CA). Read more...

 

Molded Plastic Gears Find Niche in Glucose Monitors, Magnetic Imaging Devices

Compact, lightweight components are suited for mobile devices

Although they can be as small as 12 mm OD and weigh less than 1 g, molded plastic gears can achieve reduction ratios up to 8000:1. Wave Drive technology, developed by Oechsler AG (Ansbach, Germany), has numerous applications, but the components' compact size and light weight make them particularly suitable for use in medical devices, according to project manager Frank Poehlau. Read more...

Copyright ©2002 Medical Product Manufacturing News