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Articles from 1997 In February


Biocompatibility Testing Is Needed Despite Material Supplier Claims

Medical Device & Diagnostic Industry Magazine | MDDI Article Index

An MD&DI February 1997 Column


HELP DESK

When selecting materials, medical device manufacturers must perform biocompatibility tests, even if material suppliers claim their materials are biocompatible. Paul Sordellini, a consultant with Quality Solutions, Inc. (Annandale, NJ), and a member of the Ethylene Oxide Sterilization Association, explains why such tests are necessary.

Q. Our firm is developing a device, molded in-house, that will incorporate medical-grade polymers. The device, to be part of a more complex surgical kit, will be in contact with blood and compromised tissue. We have a certificate from each of the polymer suppliers attesting that the raw materials are medical grade and biocompatible. Do we need to perform any additional biocompatibility studies on the finished device?

Sordellini: During the design phase of device manufacturing, biocompatibility studies serve to eliminate materials that, when placed in a certain environment, such as in contact with blood, may produce an adverse biological response (e.g., releasing harmful substances into the blood or reacting with any blood component). Presently, the industry lacks a universally accepted definition of biocompatible.

As a result, certification by a raw material manufacturer or supplier should not be the sole criterion for the use of any material. Even those substances generally recognized as safe according to the list provided by 21 CFR 182 should not be automatically assumed to be safe without empirical confirmation by the device manufacturer.

As part of the design process, companies should perform a complete biocompatibility study on finished and sterilized device samples. Because a raw material may undergo chemical changes during manufacturing, the samples must be exactly what firms intend to market--not simulated product samples. Heat applied during molding can induce chemical mutations and toxic substances, or particulates may be deposited on the device during manufacturing.

In addition, biocompatibility studies on finished, sterile devices demonstrate that the sterilization process did not induce harmful bioincompatibility. For example, irradiation is the application of pure energy that can cause almost any material to react or cause two components within a device to react with each other. The high temperature of steam sterilization can also induce chemical reactions among some materials that, at normal ambient conditions, seem inert. Ethylene oxide, as well as other types of reactive gas sterilants, can alter bonds on a molecular level or react with the materials, producing harmful by-products.

Choosing materials that have already been determined by the supplier to be medical grade or biocompatible is a good starting place in the design of medical devices. But manufacturers are ultimately responsible for demonstrating the safety and efficacy of their devices (i.e., biocompatibility). Companies need to select and perform the biocompatibility studies most appropriate for their devices, based on the devices' components and their intended use.

For additional information, firms can refer to the following documents:

ISO 10993--Biological Evaluation of Medical Devices, Part I: Evaluation and Testing, Geneva, International Organization for Standardization, January 1994.

Park JJ, Biocompatibility of Medical Devices, Rockville, MD, FDA, Center for Devices and Radiological Health, April 15, 1993.


"Help Desk" solicits questions about the design, manufacture, regulation, and sale of medical products and refers them to appropriate experts in the field. A list of topics previously covered can be found in our Help Desk Archives. Send questions to Help Desk, MD&DI, 11444 W. Olympic Blvd., Ste. 900, Los Angeles, CA 90064, fax 310/445-4299, e-mail [email protected]. You can also use our on-line query form.

Although every effort is made to ensure the accuracy of this column, neither the experts nor the editors can guarantee the accuracy of the solutions offered. They also cannot ensure that the proposed answers will work in every situation.

Readers are also encouraged to send comments on the published questions and answers.


Copyright © 1997 Medical Device & Diagnostic Industry

EMI and Power Supplies in Medical Electronics

Medical Device & Diagnostic Industry Magazine | MDDI Article Index

An MD&DI February 1997 Feature Article

ELECTRONICS

Electromagnetic interference can be minimized by using care when selecting and mounting supply components, and when designing filter elements.

When designing power supplies for patient-connected medical electronics, one of the biggest challenges is controlling electromagnetic interference (EMI) while maintaining the low leakage currents necessary for safe patient connection. In most electronic devices, EMI is easily controlled by integrating filters between the line power and the power supply. Y-capacitor-type filters, which connect both line and neutral to enclosure ground, are especially effective against common-mode interference.

However, where this option is restricted by leakage-current requirements, designers must rely on the only available option: installing the high-impedance series elements known as inductors, which are far less effective than capacitors at controlling EMI. The high impedances described for such filters in textbooks are not realized in actual practice, at least at higher frequencies--parasitic paths become efficient above 100 MHz, and carelessly designed power supplies and filters fail to perform to expectations. Accordingly, designers must pay attention to minimizing effects of parasitic elements.

After describing the threats to medical power supplies from EMI and the coupling paths involved, this article presents design recommendations that will help to minimize EMI without sacrificing safety.

EMISSIONS AND IMMUNITY

In the European Union (EU), both immunity to external interference and emissions from medical electronic equipment are regulated. EMI immunity requirements, which are set forth in the International Electrotechnical Commission (IEC) 601 series of standards, include tests for radio-frequency interference (RFI), electrostatic discharge (ESD), electrical fast transients (EFTs), and surges.1 Of these four tests, those for EFTs and surges are most important for designers of power supplies.

At present, there are no mandatory EMI immunity requirements in the United States, but FDA has been showing increasing interest in the issue and is working with the IEC to establish uniform requirements.2 The agency has not yet shown a similar interest in regulating emissions, and the Federal Communications Commission has exempted medical electronics (and several other equipment categories) from emissions testing. Nevertheless, for reasons of safety as well as market access, it makes sense for U.S.-based manufacturers to comply with the European requirements for both immunity and emissions, even for domestic products.

Figure 1 shows the sources of the threats to medical device power supplies from both external interference and internal emissions. The first threat involves emissions that originate in the power supply itself. All ac supplies generate rectifier noise, including rectifier switching and snap-off, and switching-mode power supplies add switching noise to the system. Such interference can either be propagated back to the power line or forward to the load. Interference that travels to the power line will show up in a conducted test and may also show up in a radiated test, especially with switchers running above 100 kHz.

The second threat is the interference generated in the device electronics. High-frequency clock noise is the most notable but noise is also generated by electric motors, especially brushless motors and those with variable-frequency drives, and relay or other power switchers. In this case, the power supply simply acts as a conduit. The power supply designer cannot control the interference source, but must attempt to intercept the noise that is conducted from the device to the supply.

The third threat is external interference that enters the power supply and either attacks the supply directly or passes through it to attack the device electronics. All types of EMI (power disturbances, RFI, and ESD) can interfere with power supplies, but power disturbances such as EFTs and voltage surges are directed primarily at the supply. A high-frequency, low-energy test is used to determine immunity to EFTs, which will easily pass through the power supply and attack the electronics within. The surge test is low frequency and high energy, simulating a surge caused by a lightning strike. While the required immunity levels are similar, the threats are significantly different.

RFI can also assault a power supply directly or can be intercepted by the power cord and conducted to the supply (generally, lower frequencies will be conducted and higher frequencies will be radiated). If the energy is conducted, it may attack the power supply itself or simply pass through to attack the device electronics. ESD does not usually affect power supplies, but when it does, its effects are much like those of EFTs. The static discharge attacks the supply's regulator, causing temporary voltage sags (or surges), or passes through the supply to get at the digital electronics.

COUPLING PATHS

EMI coupling paths, which connect the interference source with a receptor, may be conducted, radiated, or a combination of the two. Differential-mode conductive paths, with signal or supply current or interference current propagating down a wire and coming back via an adjacent return line, are the norm. Common-mode paths occur when current travels down both the signal or supply line and the return line in phase; the return is an unintended path, often to a chassis ground or earth ground.

Interference almost always originates as differential mode, but both electric and magnetic field coupling paths are predominantly common mode, which means that the farther EMI gets from its source, the higher the percentage of common-mode coupling paths. Low-frequency energy ( Because common-mode interference, which is very difficult to filter, relies primarily on parasitic coupling paths, it is important for designers to keep those paths to an absolute minimum. This involves controlling both the parasitics in the component itself and parasitics between the intended current path (traces and components) and other system members, which include other components and traces, structural members, and perhaps a heat sink. When addressing this challenge, the following generalizations should be kept in mind:

  • Because of the length of their leads, capacitors have series inductance, which reduces their effectiveness at high frequencies. Capacitors will resonate at a surprisingly low frequency, becoming inductive above resonance.
  • As a result of interwinding capacitance, inductors have shunt capacitance, which reduces their high-frequency effectiveness. In addition, open-flux-path inductors have a magnetic field extending well beyond the inductor envelope.
  • Coupling paths from the intended current path to heat sinks and circuit board traces can be a significant concern.

(These issues have been addressed in detail in previous articles.3, 4)

COPING WITH INTERNAL INTERFERENCE

A clear-cut rule for designing for EMI is to control interference as close to its source as possible. The farther EMI is from the source, the harder it is to contain the energy. In the case of power supplies, internally generated high-frequency noise from the bridge and switcher is best controlled right at the source. Properly applied, filtering at these locations can be differential mode. For the switcher, the high-frequency currents can either be blocked immediately at the switch or returned immediately to their original path. For the bridge, it is not sufficient to include only a line-to-line filter at the input or output because imbalances in the bridge currents will leave unequal snap-off spikes, which will end up as common-mode voltages; filtering to a neutral common point will help to confine these spikes to the immediate area of the bridge.

Placing ferrites in-line may seem counterintuitive to some power supply designers, who believe switches should be slammed against the rails as fast as possible to keep losses down. But such rapid switching is the primary source of internally generated noise. The application's actual switching requirements should be considered carefully before rejecting use of in-line filters. Increasingly large ferrites can be tried until only a minimal change in rise time is perceivable on the switching waveform. In most supplies, there is really no need to pass 30-MHz interference from a 100-kHz switcher.

The best way to block high-frequency currents from passing from a medical device to the power supply is to insert high-frequency ferrites in series in all lines connected with the device (including power return). The low-frequency filter elements used in the power supply design will probably not suffice to control the higher noise frequencies.

Once everything possible has been done to control internal emissions at the source, the issue of coupling to adjacent circuit elements should be addressed. The magnetic field from an open-flux-path inductor extends far beyond the footprint of the inductor, so it is very difficult to provide adequate isolation. Using toroids or, even better, pot cores, in the power supply is recommended, but it is important to make sure they perform well at frequencies well above the supply's switching frequency. Inductors resonate at surprisingly low frequencies: Any inductor used in a 100-kHz supply will almost certainly resonate below 10 MHz, rendering it ineffective at controlling interference at 30 MHz or above. Inductor resonances should be checked on a network analyzer before installation. Similarly, it is important to ensure that differential-mode filter capacitors are effective at higher frequencies. Although the new tantalum units have been described as very good at high frequencies, it is probably better not to rely on them to filter current above 5 MHz.

It is also critical to mount filter components so as to minimize coupling to printed circuit board traces, adjacent circuit components, and mechanical elements. Capacitors should be mounted with short leads, and closely spaced inductors and transformers should be placed orthogonally, even if they are toroids. Designers need to consider which is the high-noise side of these inductors, as capacitive coupling to adjacent traces and heat sinks can be considerable.

COPING WITH EXTERNAL INTERFERENCE

Although the steps described above are directed specifically at controlling and preventing internally generated interference, they are also effective for external interference. However, they are not likely to provide sufficient protection, especially against conducted EMI.

External conducted interference can be controlled by filtering or transient suppression. Transient devices such as arc suppressors (crowbars) and clamps (metal-oxide varistors and zener diodes) are designed to handle high-energy transients, such as voltage surges, but their use in medical devices needs to be tempered by safety considerations. As with Y-capacitors, transient suppressors connected between line or neutral and ground present a possible leakage path. Therefore they should only be employed if their steady-state leakage current is low enough to meet the leakage-current limits for patient-connected devices and their breakdown is sufficiently high, typically at least 500 Vrms.

If at all possible, it is preferable to use filtering alone, without transient suppressors. Generally, this means that the power supply itself must be built to withstand as much interference as possible. The designer will need to select supply components capable of withstanding any high-voltage transients that can't be blocked. High-frequency filtering is effective against EFTs, but during surges, where the high voltage is of fairly low frequency, it is likely that excess voltages will get into the supply.

Among the supply components, the converters are most at risk from external interference. Any disturbance that reaches the feedback circuit in a regulator can cause out-of-tolerance supply voltages. RFI, being a continuous wave, will cause an output-voltage error unless filters keep it out of the feedback path. Generally, this will require placing a high-frequency capacitor at both the input to and output from the regulator (see Figure 2 below). As shown in the figure, capacitors must go from input and output to circuit common, not to chassis ground. Power line transients will also attack the feedback circuit. Even brief transients can cause a long-term sag or surge in the supply voltage. Designers need to keep such currents away from the regulator.

Figure 2. Isolation of the power supply regulator with capacitors at its input and output.

CONCLUSION

EMI problems in medical electronic equipment power supplies can be prevented if designers heed the following advice. Select supply components carefully to ensure their functionality at the frequency range of interest and design filter elements to intercept interference as close to its source as possible. Also, mount components carefully to minimize coupling paths to other components, especially those that connect to the outside world.

REFERENCES

1. "Electromagnetic Compatibility--Requirements and Tests," IEC 601-1-2, Geneva, International Electrotechnical Commission (IEC), 1993.

2. Kahan JS, "Medical Device Regulatory Requirements for Electromagnetic Compatibility," Med Dev Diag Indust, 17(9):86-92, 1995.

3. Kimmel WD, and Gerke DD, "Selecting Components to Minimize EMI," Med Dev Diag Indust, 17(1):212-218, 1995.

4. Kimmel WD, and Gerke DD, "Filtering Analog Signals in Medical Devices," Med Dev Diag Indust, 17(2):88-92, 1995.

William D. Kimmel and Daryl D. Gerke are principals in the EMI consulting firm Kimmel Gerke Associates, Ltd., based in St. Paul, MN.


Copyright © 1997 Medical Device & Diagnostic Industry

Responsiveness and Planning Ensure Success in Quality Management

Medical Device & Diagnostic Industry Magazine | MDDI Article Index

An MD&DI February 1997 Column

SNAPSHOT



Peter Chevalier has taken his work to heart, literally. Chevalier is not only a vice president and the chief quality and regulatory officer of Medtronic (Minneapolis), but he is also one of its customers. Nearly half of the pacemakers in the world are manufactured by Medtronic--his included.

Chevalier joined Medtronic in 1981 as director of clinical evaluation for the company's pacing business. He was director of research and development for Medtronic's heart-valve business from 1985 until his promotion to vice president of corporate regulatory affairs. In 1993, he was named chief quality and regulatory officer.

In his years at Medtronic, Chevalier has been responsible for several quality innovations. For example, he advocated the formation of an internal quality council, a monthly meeting of senior quality professionals representing all of Medtronic's business and geographic units. The quality council sets the overall company vision, which the individual quality managers must then implement in their areas of responsibility.

Chevalier credits some of the success of the council to a focus on supporting company managers, who have to actually implement the quality policies. "We try not to be too prescriptive," Chevalier explains. "We'd much rather have them understand what we're trying to accomplish and have them develop their own ways of doing it. That way they have greater ownership."

The council also helps to ensure a shared focus within an increasingly global company, although international differences in quality and regulatory standards are rarely a concern because Medtronic has continually revised its standards upward in anticipation of ISO 9000 and FDA's quality system regulation. "We've put in place a quality management system that meets all requirements around the world," Chevalier says.

In the past, many of the company's quality improvement decisions were based on data gathered on an annual basis. "As time has gone by, we've realized that, with the marketplace moving as rapidly as it is, a once-a-year approach is not going to be as effective," Chevalier says.

Now Chevalier places a greater emphasis on continuous feedback from the company's 30 so-called listening posts. These posts include everything from one-on-one meetings with physicians and buyer groups, to surveys distributed via the Internet, a recently introduced method welcomed by many physicians.

Chevalier came to the device industry with varied career experiences in both the public and private sectors. Before his arrival at Medtronic, Chevalier, who holds a doctorate in physiology, pursued a traditional career in academic medicine, first at the University of Delaware (Newark) and later at the Mayo Clinic (Rochester, MN), where he was professor of physiology and medicine.

He then went on to spend two years as associate director of lung diseases for the National Heart, Blood, and Lung Institute (Washington, DC), an experience that exposed him to the inner workings of life within the beltway.

"Having come here with that perspective, it's made it a lot easier for me to deal with legislative committees and to really understand how the federal government operates," he says. That perspective has also helped make Chevalier a strong and effective proponent of FDA reform. Chevalier recasts the traditionally pro-business stance of calling for limits to agency regulation in terms of his concern for patients. "FDA needs to become a patient advocate--not a business advocate, and not a consumer advocate," Chevalier says. "Patients need and want access to the latest technology, devices, and therapies."

According to Chevalier, patients often do not get fast enough access to new products in the United States, where approvals for Class III products lag three to four years behind the rest of the world. Chevalier is hopeful, though, that the new Congress will pass pending legislation aimed at shifting product liability burdens away from manufacturers of biomaterials, and at forcing FDA to meet its statutory requirement of approving Class III devices within 180 days.

He hopes that FDA will evolve to face the realities of the global market. The ability to be responsive to a changing world

is, according to Chevalier, the key to succeeding in life as well as in business. Says Chevalier, "The health-care environment around the world continues to evolve, so we need to continually look at where we're headed."


Copyright © 1997 Medical Device & Diagnostic Industry

FDA's Third-Party Pilot in Need of Submissions

Medical Device & Diagnostic Industry Magazine | MDDI Article Index

Originally published February, 1997

Even after six months of operation, FDA's third-party product review pilot program isn't quite off the ground. Deemed capable by FDA of handling as many as 1500 premarket notifications a year, third parties have received only three since the program's inception.

The results of a recent informal MD&DI survey and comments from industry and third parties indicate that such low use can be attributed to a number of factors: the limited number of devices eligible for third-party review, the cost of contracting a third-party reviewer, and concerns about the reliability of the reviews.

The pilot, which began on August 1, 1996, was designed to offer manufacturers an alternative route for the review of low- to moderate-risk devices, one that potentially could yield faster product reviews than FDA. It was also intended to lessen FDA's workload by offloading certain 510(k) applications to third parties, enabling FDA to focus on higher-risk devices. The agency had originally intended to judge the program's performance during its second year, but concern about its infrequent use has prompted FDA to invite industry and others to comment on how to make the program more attractive to manufacturers. Otherwise, if pilot use remains low, FDA won't have enough data to test the feasibility of third-party review.

"FDA had a good philosophical approach, but a bad implementation," asserts Jeff Kimbell, executive director of the Medical Device Manufacturers Association (MDMA; Washington, DC). Arguing that manufacturers do not want to pay third parties for reviews that FDA is already completing in less than 90 days, Kimbell suggests that FDA expand the pilot to include Class II products that do not need clinical trials for approval.

Dee Simons, associate vice president at the Health Industry Manufacturers Association (Washington, DC), predicted such a problem with the program last year in a June 3 letter to FDA. "Manufacturers may not want to contract with a third party because FDA is already meeting the 90-day review time for most of the devices in the program." She also noted that FDA would not be significantly reducing its workload, estimating that the "review time saved is probably less than 5%."

Carole Stamp, 510(k) program manager at TÜV Product Service (New Brighton, MN), one of the seven third parties recognized by FDA, agrees that the number of eligible Class II devices needs to be increased. Citing many inquiries from manufacturers of Class II devices that are not eligible for participation in the program, Stamp believes that "these manufacturers seem to be more receptive to the third-party review program because they see a potential to significantly reduce the review time." She concludes that "as more Class II devices become eligible, manufacturer participation will increase."

MD&DI readers expressed other concerns. David Kunin, a manufacturing consultant who has experience with in vitro diagnostics, electronics, and disposables, asks, "Why pay twice for a tax-supported FDA activity?" MDMA's Kimbell, who represents 130 entrepreneurial device manufacturers, agrees that the additional cost is a burden on smaller companies.

Susan Alpert, director of FDA's Office of Device Evaluation (ODE), however, says FDA is surprised that more manufacturers aren't using the program. She realizes that it costs them additional money, but "generally all of us are willing to spend a little extra money when we can get something in return."

Another issue raised by readers was the uncertainty that third parties could perform reviews as fast as or faster than FDA. But, according to Nancy Sauer, president of RDD Consultants, Inc. (Louisville, CO), her firm's recent completion of the only two third-party reviews submitted to FDA and the agency's ability to finish its reviews, all in 51 days, shows that third parties and FDA can work together to reduce review time. Sauer explains that additional studies were required for these reviews and complete 510(k) submissions should be reviewed more quickly.

ODE's Alpert also feels that the program offers manufacturers the "opportunity to cut time from the review process by negotiating with an entity that doesn't have a lot of other work on its plate." Speaking at FDLI's annual meeting last December in Washington, DC, she noted that in-agency 510(k) reviews comparable to the ones completed by RDD Consultants were running a little over 100 days, a review time twice that required for the two reviews completed under the program.

Finally, readers are concerned about a third party's ability to handle 510(k) submissions. "Factors that would sway me to use--or not to use--a third-party reviewer include the third party's understanding of technology, product requirements, and the marketplace," explains Paul Martakos, senior research scientist at Atrium Medical Corp. (Hudson, NH).

Kimbell isn't surprised at such skepticism. He believes that until FDA includes recognized leaders in medical treatment, manufacturers will be concerned about the lack of expertise.--Daphne Allen

Consolidations Put the Squeezeon Small Manufacturers

Medical Device & Diagnostic Industry Magazine | MDDI Article Index

Originally published February, 1997

Small medical manufacturers are feeling squeezed by rampant industry consolidation and see dwindling prospects for success and survival--at least, that was the underlying theme at "Winning in the New Era of Health-Care Industry Consolidation," a seminar sponsored by the Health Industry Manufacturers Association (HIMA) last December. Throughout the conference, repeated references to Columbia/HCA (Nashville, TN) drew participants into two camps--the small manufacturers who view the giant as a symbol of a system gone awry, and the analysts who lionize it as a model for efficient and dynamic management.

Speakers such as Ray Larkin, president and CEO of Nellcor Puritan Bennett (Pleasanton, CA), for example, avowed that Columbia "is not trying to beat the daylights out of its suppliers." Columbia, he said, has acknowledged the importance of maintaining reasonable margins and knows that it's impossible to form an alliance with a company that's going out of business. Molly Coye of HealthDesk (Berkeley, CA) pointed to an increase in the efficiency and profitability of a hospital recently taken over by Columbia, noting that the organization's vast capital resources were pivotal in instituting necessary upgrades to equipment and information systems.

On the other hand, some manufacturers expressed concern about their access--or rather, lack of access--to the big group purchasing organizations (GPOs). Francis Lavin, president and CEO of MicroAire Surgical Instruments (Valencia, CA), seemed to strike a chord when he stood up from the audience and explained, "We've been lowering our prices for the past three years. Our problem isn't that we're not willing to help, it's that we're not even being asked to sit down at the bidding table."

To judge from the tenor of the conference, it's evident that the GPOs, growing in size but decreasing in number, simply don't have time to talk to smaller suppliers. From their perspective, it's far more efficient to stay on top of a few huge deals than to manage a vast number of smaller contracts. And suppose a small manufacturer does win a contract from Premier Health Alliance (Westchester, IL) or a similar group--will that manufacturer have the facilities in place to handle an overnight jump to a 20% market share?

How are manufacturers expected to plan strategically in an industry that has seen, according to Connie Woodburn of Premier, one out of five community hospitals change hands in the last two years? Nellcor's Larkin suggested that in the long run, companies that don't have a differentiating technology or product and want to grow will have to have their products taken up as part of a larger company's line, simply because larger companies "are perceived as better partners." Suppliers need to reach a "critical mass" just to get noticed by the big purchasing groups, and decisions in the coming months might well determine whether a company finds itself on the buying or selling end of an industry deal.

Still, one participant recounted his success in assembling a group of small suppliers to target the gaps in the large purchasing contracts, focusing on those commodity items that are too inexpensive to receive coverage as part of a large plan. At that point, he said, "you switch from being a sales rep to being a resource provider."

More than one panel stressed the importance of being a resource provider rather than a mere product supplier. According to Bill Cleverley at the Center for Healthcare Industry Performance (Columbus, OH), "there is tremendous opportunity for cost reduction in the hospital industry" and those manufacturers who can help develop strategies and protocols to increase efficiency will gain a marketing edge.

Some hospitals, for example, are using the equivalent of statistical quality control to help physicians isolate their own best practices. Armed with quantified data about which products work best at each hospital, administrators will revamp their purchasing strategies and specify only those devices with a proven track record. Suppliers can curry favor by isolating which procedures truly benefit from a particular product and which applications are superfluous.

Naturally, some manufacturers will have a hard time swallowing this idea of "utilization reduction," which essentially boils down to teaching hospitals how not to use their products. Raising more than a few eyebrows, Brenda Clayton of Tenet Healthcare (Santa Monica, CA) suggested that suppliers might make concessions to permit more resterilization of disposable devices, intimating that the practice is already widespread. "Hospitals," she said, "would far rather work with the original manufacturer in this case than with a freelancer."

Part of being a resource provider entails developing the quantifiable data to support product claims. Gary Bang, president and CEO of Target Therapeutics (Fremont, CA), described an extensive campaign involving outside consultants to generate end-cost information simultaneously with clinical outcomes data. Hospital administrators, he said, look very carefully at return-on-investment information. Mike James explained how Medtronic (Minneapolis) assembled data showing that their pacing devices, when placed in elderly patients, could prevent broken bones caused by falls during cardiac episodes.

On the other hand, Bill Mavity, president and CEO of InnerDyne Medical (Sunnyvale, CA), described the extensive cost-savings analyses that his company performed. Even though the results were "quite positive," he said, "we still had trouble getting into the supply chain."

It's clear that sales can't be negotiated in the traditional manner and that physicians are relinquishing decision-making power. Manufacturers can only throw up their hands when an orthopedic surgeon flatly says, "If you've got a great orthopedic product, don't come to me with it because I can't do anything about it." As William Mohlenbrock, MD, of Iameter (La Jolla, CA), declared, "You're going to have to get out of the business of sending someone into my waiting room."

Ruth-Ellen Abdulmassih of Abbott Diagnostics (Santa Clara, CA) demonstrated the difficulty of identifying the appropriate management level for formulating deals, and predicted that in the future there will be less need for salespeople in targeted accounts and more need for technical assistance. Joe Mulroy of Amerinet (St. Louis) favors a sales strategy that begins with educational seminars for hospital executives and then works with individuals on the lower tiers. Manufacturers can help, he said, by being part of the group that works to overcome resistance down the ladder.

Manufacturers should also bear in mind that integrated information systems relay purchasing decisions to representatives across the country. As Clayton said, manufacturers will not get away with quoting one price for a hospital in South Carolina and another for California.

Several speakers and audience members offered hope that future sales pitches will be made on the consumer level as health-care delivery aspires to the same high status as Nike sneakers. The baby boomers, if adequately informed, can bring tremendous market pressure to bear on the purchasing decisions of health-care delivery centers. As one audience member suggested, "If the baby boomers think that innovation will stop just when they need it, you can bet there will be a new interest in innovation." The Internet, for example, is becoming far more accessible and user-friendly, and manufacturers might use this technology to sway consumers directly.

Most of the small manufacturers represented at the conference feel more threatened by industry consolidation than by FDA crackdowns. "Managed care" in reality has come to mean "managed cost," and margins are reportedly shrinking all over. In the view of these manufacturers, the health-care industry has always relied on the technical innovations generated by small suppliers, and without such innovation the industry will certainly crumble.

But the picture is not necessarily bleak. Dominated by a philosophy of disease management, the health-care industry is already beginning to emphasize diagnostics over therapeutics. Linda Sonntag of Axiom Venture Advisors (San Francisco) predicted that the human genome project will revolutionize health care in the next 10 years. "Population-based managed care won't work," she declared, because it requires large expenditures for diagnosis and treatment of existing disease.

But in the future, she said, physicians will diagnose predispositions rather than conditions. By enabling physicians to deal with an individual's condition at an early stage, the genome project will bring patients back to health care's center stage. That doesn't mean that physician care will again function as a cottage industry, but a return to more personalized health care will present greater opportunities for manufacturers of all sizes.--Gabe Spera

MR Innovation to Allow Scansof Standing Patients

Medical Device & Diagnostic Industry Magazine | MDDI Article Index

Originally published February, 1997

The painful back and knee problems that convince patients to seek medical attention are not always obvious on magnetic resonance imaging (MRI) scans. Fonar Corp. (Melville, NY) believes one reason may be that the forces causing at least some of the pain are reduced when lying down. For that reason, Fonar is developing the first MRI scanner that images patients while standing.

Shown as a work in progress at the annual meeting of the Radiological Society of North America last December, the stand-up MRI is essentially a Quad 7000, the company's 0.35-tesla scanner, flipped on its side. Sandwiched between two electromagnets, the patient would stand on a platform that rises or drops into a position suitable for scanning the target anatomy. "Every magnet has what's called a sweet spot--the area where its imaging uniformity is best and you get the best images," says Kurt Reimann, Fonar's director of marketing. "So depending on what's being imaged, we can raise or lower the patient to get him or her right in the sweet spot of the magnet."

A commercial product is still at least two years away, as engineers are now tweaking the design. The market is expected to be sports medicine clinics and trauma centers.--Greg Freiherr

Manufacturers Move Ahead to Meet New Regulations

Medical Device & Diagnostic Industry Magazine | MDDI Article Index

Originally published February, 1997

Many manufacturers are not hesitating to begin following FDA's new quality system regulation. A recent survey of the medical device industry in Minnesota by Medical Alley (Minneapolis) found that 9 out of 10 respondents have already started to bring their procedures in line with the new requirements. On the survey, which had a response rate of about 30%, nearly half of the respondents reported being near to completion of their efforts to comply, and 16% said that they have actually completed this process. The standards will require ISO 9000 record-keeping systems, and half of the respondents reported that they were already ISO 9000 certified.

The regulation does not come into effect until June 1, 1997, and the design control provisions will not be enforced until after June 1998. According to this survey, many companies will be ready to meet these new standards. Three-fourths of respondents also reported they felt the timetable for compliance was acceptable.

Tom Meskan, the president of Medical Alley, says, "We weren't sure what to expect from this survey, and it was interesting to see that such a large percentage of manufacturers were already getting started meeting the requirements." According to Meskan, however, the most important result of the survey was that it provided the opportunity for a useful interchange between FDA and industry. Meskan says that the association plans to conduct future surveys of industry on this issue.

Medical Alley, with 230 members from medical device companies, hospitals, clinics, health plans, research facilities, and other groups interested in regulatory issues, also plans to continue its efforts to communicate with FDA. The survey results were announced last November 14 at a joint meeting of Medical Alley and the Minneapolis district office of FDA.--Leslie Laine

Medical Device Packagers Honored for Innovation

Medical Device & Diagnostic Industry Magazine | MDDI Article Index

Originally published February, 1997

Four medical device packagers were recently honored for their products by the Institute of Packaging Professionals (IoPP; Herndon, VA). Winning awards in the medical device packaging category of IoPP's AmeriStar Package competition, the companies were recognized at a reception during Pack Expo last November in Chicago.

In 1996, the four winners in the medical device category were one Gold Star recipient and three recipients of the Judges Award of Merit. Sabin Corp. (Bloomington, IN), the Gold Star winner, was honored for producing the first ultraviolet light­absorbing and transparent laminate suitable for sterile medical device packaging. The clear laminate protects devices from ultraviolet rays. Working in conjunction with Courtaulds Performance Films (Martinsville, VA), Sabin spent three years developing the packaging.

The merit award winners were Rexam Medical Packaging (Vernon Hills, IL), for its Integra tear bag, made of a proprietary blend of heavy-duty, coextruded low-density polyethylene; Boston Scientific Corp. (Watertown, MA), for its thermoformed tray and lid, designed to protect the company's Symphony nitinol stent, a permanent implant that is used in blood vessels and bile ducts; and Tolas Health Care Packaging (Feasterville, PA), for its T-VL pouches for packaging high-profile medical devices such as orthopedic implants and artificial joints.

The competition was open to both members and nonmembers of IoPP. For more information, contact IoPP at 703/318-8970.--D.A.

Quality Systems on the Fast Track Toward Implementation

Medical Device & Diagnostic Industry Magazine | MDDI Article Index

An MD&DI February 1997 Column

For more than three years, Kim Trautman has been at the center of FDA's efforts to revise the medical device good manufacturing practices (GMP) regulation. Now issued as a quality system regulation that incorporates GMP requirements, the new regulation will take effect on June 1, 1997. But getting the regulation published was far from the final step for Trautman, who has also been intimately involved in producing educational materials to get industry ready for the transition.

Now the burning question is, "How is industry responding?" In this interview with Steve Halasey, editor of IVD Technology, Trautman evaluates industry's progress toward understanding the requirements of the new regulation and explains FDA's next steps toward implementing it. From Trautman's description, it appears there's still a lot of work to do on both sides.

Q. What concerns has the agency heard from device manufacturers since the quality system regulation was published in final form in the Federal Register last October?

A. In general, companies are asking the agency to be more prescriptive. That seems a little odd to me, since industry comments on the drafts issued over the past three years have urged us not to be prescriptive. The new regulation leaves it up to manufacturers to determine, develop, and document their procedures. They're responsible for telling the agency how they're going to implement the regulation, and for justifying the way they choose to do so.

Q. Are companies suggesting that they want additional or more-prescriptive guidance documents?

A. Well, they just want the answers. They want to know how they're supposed to implement the regulation. But there are so many different ways of doing it that the agency really didn't want to be prescriptive. Companies may not like it, but the answer is that they will have to decide how to implement the regulation. They have to think about it with respect to the size of their own organizations and the risk levels of their products, and then devise an appropriate program.

Q. How will the new regulation change the ways that companies think about quality?

A. It's going to force manufacturers to integrate quality into every part of their process, and to think of quality more as a system than as a discrete function. They'll have to understand the relationships among corrective and preventive actions and the design, R&D, manufacturing, and management functions of their companies.

No matter how a company chooses to implement the regulation, it's going to force them to establish better communications among functional areas. QA professionals aren't going to be isolated anymore; they will have to interface with management, with R&D professionals, and so on.

Q. Are managers and others using FDA's educational materials as much as you'd like?

A. I'm still seeing the same types of people at conferences. Managers know the regulation is something new, and they're sending their people to conferences, but I don't think managers have begun to go to the conferences themselves yet.

Hopefully, once the RA and QA people get educated they will convey to their bosses what management is responsible for, and then maybe the bosses will start wondering what they have to know. We have to let the RA and QA people have enough time to learn the new regulation and give feedback to their management.

All of this should help RA and QA personnel to implement the regulation. Just like anywhere else, when you have command emphasis from your boss it gives you a much stronger leg to stand on.

Q. Overall, is the phase-in period that lasts until June 1 going as smoothly as you had hoped?

A. It's going smoothly, but I'm still very disappointed at how few people have read the preamble to the regulation. The preamble is an important statement because it expresses the intent of the regulation and provides an administrative record of its development. The preamble can also be used in a court of law to establish the agency's intent, and that gives it legal standing higher than that of a guidance document. More practically, the preamble helps manufacturers understand the complications that have arisen over the years, and why the agency decided on the rules that are included in the regulation.

By reading the examples and guidance included in the preamble, companies can come to a much better understanding of the regulation as a whole. But I can tell from the questions I receive at conferences that some companies haven't done this homework yet. For example, attendees ask about the use of prototypes, which is covered by several paragraphs in the preamble [comment 80], or about the distinction between critical and noncritical devices, which was eliminated in the first proposed revision of November 1993 [comment 4]. These questioners clearly haven't read the preamble or the previous proposed versions.

To me, this is the single greatest source of frustration. The agency has made a lot of educational materials available, but the single most important source of information is the preamble. If I could get across one point to manufacturers, it would be to read that document.

Q. Are there particular sectors of industry--IVD manufacturing, for instance--where additional guidance from the agency might be necessary?

A. Not really. The quality system regulation is very broad and has been designed to cover a wide range of products. There are many kinds of medical device technologies, each with its own risks. Manufacturers know their own products and the risks they carry. Each manufacturer has to develop a quality system program commensurate with the products it's developing, keeping in mind the size of the company.

The questions that a manufacturer has about the regulation will tell it what needs to be justified, and that will lead the manufacturer to the point of considering what type of quality system to establish and how to justify that system. Companies have to adjust their procedures to fit their own cultures, but for most companies simpler is probably better.

But companies have to find a middle ground. Their procedures shouldn't be

so strict that they offer the company only one way to satisfy the requirements, nor should they be so loose that the company doesn't derive any benefit. If a company's procedures don't make good business sense, then something's wrong with the way it's approaching the regulation.

Q. What other pitfalls should companies avoid in devising their quality systems?

A. The regulation gives companies a lot of flexibility and frequently uses the phrase where appropriate. The worst thing a company can do is to adopt that phrase into its own procedures. The agency expects that the company's procedures will define the circumstances under which it will perform a certain test or task.

Using the phrase where appropriate in a procedure is probably one of the major red flags that I will be talking to FDA investigators about, because it means that company management has not provided its personnel with guidance. What does this phrase mean to manufacturing personnel? Will they know what to do when they encounter it? By giving manufacturers flexibility, the agency intends that they should use it, not just pass the buck.

Q. How can device manufacturers avoid this trap?

A. When the regulation uses the phrase where appropriate, the manufacturer might create a procedure that explains when the requirement is appropriate and presents its justification for that decision. But the situation may not always be that clear-cut. So the manufacturer might choose instead to include a decision tree or rationale that can be used to determine when the procedure is appropriate. Both approaches are acceptable.

Q. What about the use of electronic systems and automated tools for implementing the regulation? Have you seen an increase in their use by manufacturers?

A. Over the past four years there has definitely been an increase of activity in this area. A lot of companies are developing software for calibration, for documentation, for compiling the device master record or device history file, for complaint tracking, and so on. Each company has to decide which tools are appropriate for it, for its products, and for its environment.

The agency will avoid trying to determine which of these programs is better than another. All we're concerned about is if a manufacturer does use an off-the-shelf software package that it meets the requirements under 21 CFR 820.70(i), which requires that software be validated for its intended use.

Q. How will the agency be carrying out inspections for the new design control requirements?

A. A draft of the strategy was placed on the device center's web site in late December. We have tried to get as much comment as possible so we can be sure what we're adopting will meet with industry expectations. The tricky thing was that we needed to have industry comments by the end of January so we could compile them for the March 12 teleconference on design control inspections.

We're now working on finalizing the document so we can go ahead and teach both industry and agency personnel. The teleconference and regional meetings that will occur in April and May will address those topics--design controls and how we're going to inspect design controls. So when June 1 arrives, companies should not be surprised about what questions investigators will be asking.

Q. Is there a danger that the strategy document will make investigators fall into a checklist mentality?

A. That danger was on our minds, and that's why we didn't go to a pure checklist approach. Instead the strategy uses more of a leading-question approach. In fact, we didn't allow questions that would have simple yes or no answers. When it's all finished, the document will include the text of the requirements, the questions that investigators are supposed to ask, and blank lines for the investigator to fill in. The final report will act like a combined FDA-483 and establishment inspection report for design control.

The strategy is going to structure what investigators ask, but not so much that all they have to do is check yes or no. Both industry and investigators are going to have to do some work to complete the questionnaire. That way both groups will learn, and that's what we want to happen during the transition year--learning and understanding.

Q. What is your sense of how well prepared companies are for meeting design control requirements?

A. We're not sure. A lot of companies have been working toward ISO 9000 certification, and now they're adapting their systems in order to be ready by June 1. On the other hand, some start-up companies seem mesmerized and awestruck by the whole thing. That scares me.

At this point, since we're not yet inspecting, I have no idea which of these extremes is most typical. Unfortunately, most conference attendees are from companies that can afford to send their people, and they're probably a little bit better prepared than the companies we're not hearing from.


Copyright © 1997 Medical Device & Diagnostic Industry

Using a Matrix to Incorporate Values into Products

Medical Device & Diagnostic Industry Magazine | MDDI Article Index

An MD&DI February 1997 Column

DESIGNER'S TOOLBOX

Developing products that meet the needs of all stakeholders requires
a tool that measures and scores those characteristics.

It's easy for an engineer or industrial designer to get pointed at the wrong target and to develop wonderful solutions to the wrong problems. Using a Product Value Matrix helps design teams identify and focus on the right problems. This matrix is a unique research tool developed by Ronald J. Sears, PhD, at the Design Consortium (Worthington, OH). This flexible tool enables designers to focus on the value of the total product system, rather than just adding new features to existing designs.

Forming the Product Value Matrix starts by identifying all the people who have a stake in a product, both inside and outside the company. Internal product stakeholders include members of corporate planning, marketing, sales, manufacturing, engineering, shipping, and service department. External stakeholders include patients, clinical staff, and hospital administrators, as well as facilities managers, refurbishers, and others.

The design team identifies product interactions for each of the above stakeholders by interviewing or observing people using the product. Each person's interaction with the product and their related needs and values are placed into a matrix. For each interaction, the matrix has categories of value, including purpose, physical design, cognitive factors, aesthetics, and emotions. An example might be for the maintenance technician (a stakeholder) to change a filter or adjust a setting (product interaction). This matrix provides a specification of each stakeholder's values in the outcome of the product design. With this information, a research team can begin to explore the importance of these values and determine how essential each value is to the resulting product.

BENCHMARKING COMPETITION

Competitive products are benchmarked using the key product interactions already identified by stakeholders. Using the example of changing a filter, the team rates how easy it is to change a specific filter (low=1; high=4) and notes why the best design works well.

By calculating and plotting overall scores against market price, it is possible to map out which designs provide the greatest value for the stakeholders. The designer's goal is to ensure that any new product scores significantly better than currently marketed products.

Figure 1. Plotting benckmark scores of a product's value in relation to its market price shows how close it comes to its estimated fair value. For example, products D and E are priced fairly and product F is an exceptional value for the price.



The benchmark scores verify that the design team is addressing the issues most important to the most stakeholders. The team knows how well current products provide value in the interactions--where they have succeeded and where they need to improve. Benchmarking this information against competing products shows the design team additional opportunities for designing a more valuable product. The matrix also provides a chance for the designer to identify those situations where a single, efficient design improvement creates value for a large number of stakeholders. Designers can determine whether a task can be eliminated or simplified to improve ease of use.

This information becomes the basis for innovation sessions to launch the conceptual design with a targeted set of design opportunities. The design team can be confident that it is creating solutions that will be highly valued by product stakeholders. In addition, the benchmarking scores of current competitive products can be used to determine pricing and predict relative financial performance in the marketplace.

Jerry Proctor is a principal at Bally Design (Pittsburgh, PA).


Copyright © 1997 Medical Device & Diagnostic Industry