When it comes to medical devices, design can be a matter of life or death.
No other industry has higher stakes or demands when it comes to instrument precision, long service life, low interference, and noise than the medical field.
The industry has evolved exponentially in the last century. In response to the ridiculous and often terrifying reports of medical quackery, the Food and Drug Administration (FDA) was formed in the United States, as was the National Institute of Health (NIH) and various industrial labs which emerged from large corporations like General Electric.
GE founder Thomas Edison set up the first industrial research lab in 1910 out of which emerged the X-ray machine. What once was as a big expensive machine which incurred some fairly heavy financial losses initially became one of the most important diagnostic tools in the modern world.
The NIH started its life after the stock market crash in 1929, initially focused on basic public health issues. NIH saw its role expand and came into its own after World War II. Wartime research provided a huge boost to the medical design field, which was suddenly flush with cash from private sector investment and universities.
Medicare arrived in 1966, as did the notion of medical inflation. While costs skyrocketed, so did innovation. Even NASA got in on the action, providing significant resources for basic science and specifically for material science research that became essential to medical device development.
In the 1970s, the NIH diverted many of its resources away from universities to other sources, prompting universities to seek out private partnerships—a trend that continues to this day.
Of course, entrepreneurship too has always been associated with the medical market, and after the dotcom boom and bust many entrepreneurs turned their attention to harnessing the power of technology and tying it to medical design.
Taking Medical Devices to a New Level
Today’s medical devices not only have to keep up with extremely stringent regulations, but also hospital and patient preferences. Most need to be waterproof for easy sterilization, portable, durable, able to work on backup power and deal with voltage dips and spikes if they require constant current. They also need to be affordable and quiet.
While the industry continues to be plagued by challenges such as cybersecurity concerns and uncertainties such as the fate of the medical device excise tax, the outlook for the future looks promising. The last couple of years have been landmark ones for medical device revenue and investors are bullish about future prospects. Medical technology sales are predicted to reach more than $529.8 billion by 2022, growing at an annual rate of 5.2%. R&D expenditures are precited to grow by 4.3% annually to reach $34 billion by 2022.
Particularly since the passage of the Affordable Care Act, the drive to reduce costs in the medical space has increased significantly. There has also been a move to shift hospital costs to medical therapies at home, and more and more people are using “wearables” to track their health on the go. This demand has launched a slew of new portable devices, many of which incorporate modules consisting of miniature diaphragm pumps and solenoid valves—fluidic components which can be tailored to the system criteria that best achieve the market demand objectives.
Electronics play a major role in medical devices. There isn’t much room for error in the medical industry. The same is true for the motors and gears that power the equipment medical professionals depend on every day. Motors used for medical applications must be robust in their design, they have to be reliable, and they need to operate quietly and efficiently while being cost-effective. Medical device components also often need to be washable or waterproof to varying degrees, portable, long-lasting, able to deal with voltage spikes, and be able to run on backup power if necessary.
Home is Where the Heart (Monitor) is
Advancements in medical technology and the development of non-invasive and minimally invasive surgical procedures have contributed to growth in outpatient and ambulatory care. In many cases, surgeries once requiring several days of postoperative observation and care have become same-day procedures.
Outpatient procedures are also significantly less costly, so there’s an increase in the number of procedures being performed as outpatient and ambulatory procedures that were once performed only on an inpatient basis.
This trend for medical practitioners to reduce patients’ hospital stays and shift treatments to home has required medical device companies to engineer systems to be more portable, quieter, and more cost-effective.
The high-technology diagnostic and therapeutic services now available in the home include transfusion therapy, dialysis, oxygen therapy, mechanical ventilation, compression therapy, and wound therapy. Needless to say, this changing healthcare landscape is driving explosive growth in the medical device field. The market will continue to accelerate as demographics and market drivers increase their pressure for new product offerings.
New Materials Expand Medical Horizons
“Today, we have things that are not just devices that go on your body, but devices that go in your body, and I think that’s the big transformative technology,” said Karen Panetta, IEEE Fellow and Dean of Graduate Engineering at Tufts University. “We have new materials like smart bandages that can detect infection or your rate of healing. We have microneedles, we leverage 3D printing and laser micromachining, we have new sensors that can target chemicals and look at your dietary intake for diagnosing diseases.”
Panetta attributes much design development in the medical space to sensors and the development of sensor technology, as well as the massive leaps forward in computing power, combined with additive manufacturing and 3D printing. New materials, she says, are also revolutionizing the industry. “Silk tissue has been a fundamental game-changer,” she noted.
Indeed, spider silk has become a bit of a darling in the medical industry, with its high tensile strength, recognized as some of the strongest natural biomaterial on earth. While a limiting factor is that spider silk is relatively difficult to mass-produce at consistent quality, researchers have found that when combined with fibroblast cells from mice or other lab animals, it can form a sort of “bio-ink” which can be fed into a 3D printer and printed out where it goes from a gel-like state to a firm one rather rapidly.
The silk molecules wrap themselves around the animal cells to form a sort of porous matrix for growth, enabling scientists to print out tissue-like structures that are both stable and functional. This has allowed researchers to “print” things like heart muscle tissue out of spider silk, providing a huge boon to patients who have suffered from heart attacks and or strokes.
Some companies, such as Swedish-based Spiber Technologies AB, add in items like genetically engineered bacteria and protein purification technology to increase the quantities of spider silk protein they can generate in a variety of shapes and sizes, from fiber to foam, to film and even mesh. The company says the material can remain stable at temperatures of up to 267°C (512°F) and can be used for heart tissue regeneration, skin cell growth, bone reconstruction, and even vaccines.
In addition to groundbreaking new materials like spider silk, even more mundane material changes like switching from metal to enhanced plastics make a big difference, especially when it comes to lowering costs for new medical devices.
Plastics can be used to replace even the strongest and stiffest steel devices by incorporating simple design modifications.
High-performance polymers, for example, can offer the same level of strength and rigidity as some metals at ambient temperature, with various advantages including lower costs, enhanced aesthetics, and ergonomic improvements. High-performance polymers can also be colored, which may sound vain, but is incredibly useful in a busy operating room where various devices need to be located and differentiated from one another quickly. Polymer-based devices are also strong, durable, and can be repeatedly exposed to disinfectant.
Sensor Sensibility
Panetta also had much to say on the subject of sensors, which, conceptually sound larger than they actually can be thanks to nanotechnology and 3D printing.
“With 3D printing, you always think of something as a giant, but you can 3D print something that can go inside the body on a nanoscale. These are sensors that can go into your body and replicate. They can measure things we could never measure before without being intrusive.”
Panetta gave an example of sensors being built for Parkinson’s patients, which can be embedded in the body, measure one’s risk of having tremors at any given moment, and then use some electrical stimulus to stop those tremors.
“Not only are we nano-scaling sensors, but we’re also building them out of the natural materials we discussed before, like spider silk, and these types of sensors are incredibly versatile and can be used for all kinds of things—even things like time-release medications directly into the system.”
Panetta said what’s doubly fascinating about these types of methods is that they aren’t just using traditional scientific methods and techniques, but also borrowing from fields like acupuncture when it comes to where best to place sensors.
The exponential increase in computer power has also revolutionized the industry.
“Today we have the power to simulate and use artificial intelligence and huge computing power to profoundly experiment and really look at all the different scenarios,” said Panetta. This, theoretically, should make the path to approving new devices quicker, and yet it is taking the FDA time to catch up.
Regulations: A Help and a Hinderance
Even as the FDA’s influence helped improve overall health care, the regulatory restrictions remain stringent. Indeed, any medical designer, scientist or engineer knows the pain of navigating the FDA’s bureaucracy.
To start, designers building a new device must first determine the appropriate FDA classification for their medical device or diagnostic product, and then select a premarket submission pathway.
It is also worth noting that any changes to a product, even an existing one, can be a very big deal. For example, if one is redesigning a product that has been on the market for a decade, and a decision has been made to switch out the motor or change anything related to the drive system, the product will have to be resubmitted to the FDA in some fashion. Large companies often have ways of expediting this process, but a good rule of thumb is to plan on about nine months just for the filing to be completed.
It’s also not immediately obvious what items should be filed under.
Typically, and there are plenty of exceptions to this, if a technology is the same as (or substantially equivalent to) a currently marketed device, then one has to file a 510(k). This can take between nine months to a year to get approved. If not, or if the device falls into Class III (the riskiest medical devices), then one has to obtain premarket approval (or PMA). These can take about two years to get approved.
Around 90% of medical devices brought to market in the U.S. go through the 510(k). About 70% of 510(k)s are traditional, 22% are special, and 3% are abbreviated. Only about 5% of devices brought to market are PMAs.
For reference, it costs about $31 million to bring a medical device onto the market under the 510(k) pathway, compared to about $94 million for PMA.
The remaining 5% of devices are brought to market using one of five additional pathways: de novo, the humanitarian device exemption (HDE), the product development protocol (PDP), the custom device exemption (CDE), and the expanded access option (often referred to as the compassionate use or emergency use provision).
Changing Definitions
Classifying some of the newer innovations can prove challenging.
“The definition of medical devices has changed. They used to just be instruments before, then we moved into the digital stuff and now we have medical devices that are approaching artificial heart and body organs, with living tissue which now falls under medical devices,” said Alam Hallan, director of pharmacy at Guelph General Hospital in Guelph, Ontario, Canada.
“Think what the definition of cyborg was back in the day and compare it to some of the experiments and successful trials that have been done, where amputees have been able to work with machines to control their artificial limbs using neural networks. We’ve come to a point where we have very dexterous mechanical limbs that connect to your own nervous system. I think that’s what the definition of the cyborg is.”
Indeed, robotics and human machine interfaces are incredible, but also incredibly frustrating to get through the regulatory system, as they require human trials which are not easily conducted or cheap.
“Human machine interface is the next horizon—it’s no longer a far-fetched dream.”
Women’s Health (And do Modern Medical Devices Actually Enhance it?)
All progress is good progress, right? Not exactly, as it turns out, especially in areas pertaining to women’s health. One case where innovation hasn’t done much to improve outcomes is in fetal monitoring.
Fetal heart monitors, as the name suggests, monitor fetal heart tones through the mother’s abdomen. The history of listening to heartbeats goes back to the early 1800s, when French physician René Théophile Hyacinthe Laënnec invented the stethoscope. Laënnec’s first stethoscope was just a rolled-up sheet of paper he made into a sort of ear trumpet, which he used to listen to a young woman’s heartbeat instead of putting his ear directly onto her chest. Surprisingly perhaps, the crude tool did a fine job, and later the paper version was recreated in wood.
By around 1822, listening to the fetal heartrate through the mother’s abdomen with a wooden stethoscope became common practice and worked well. Meanwhile, the first fetal electrocardiogram (EKG) recording took place in 1906, though continuous electronic fetal heart rate monitoring wasn’t introduced into hospitals before the 1970s. When it was, however, it was brought in without any evidence to support it from clinical trials. The machine had a powerful lobby and a lot of marketing effort behind it, with its makers claiming (with no solid scientific proof) that it would be a breakthrough, able to predict fetal distress and bring an end to cerebral palsy, still the most common childhood motor disability today. Hospitals embraced it with open arms, as did physicians and nurses, and yet women patients were not told that the EFM was entirely experimental and unchecked.
In today’s hospitals, EFM machines are a nonnegotiable in any labor and delivery room, though they still lack scientific evidence to show they have benefits over simple auscultation. Indeed, the site Evidence Based Birth notes that “as the use of EFM during labor increased, so did the Cesarean rate, and it is possible that these two trends are connected.”
In fact, between 1970 and 2016, the Cesarean rate in the U.S. increased from 5% to 32%, with “non-reassuring fetal heart tones” the second most quoted reason for first-time Cesareans in the U.S. according to ACOG (The American College of Obstetrics and Gynecology). Not all progress, then, it seems, is entirely useful.
The Next Decade of Devices
As we move into the next decade, with burgeoning computer power for better simulations and modeling, the medical device industry is on a continuing boom trend, while organizations like the FDA struggle to keep up and adapt to the sheer volume and pace of innovation.
Tech behemoths like Google, Microsoft, Amazon, and Apple have also entered the healthcare sector, applying an army of resources and talent to the pool.
Floods of data are expanding our capabilities in the design of clinical trials, while improved imaging is also significantly changing the way physicians are able to diagnose and deliver care.
Coupled with the rise of artificial intelligence, machine learning, IoT, and mobile technologies, the future is going from sci-fi to sci-fact really fast.