Designing for scalability...
How to use design and engineering principles to develop a medical product that can be reliably manufactured at scale
In last weeks article, I provided an overview of the product development process in healthcare, emphasizing how each stage is interconnected and crucial to the successful creation of a medical device. Today, I write about the practical aspects of designing your device, with a focus on maintaining engineering and design controls that not only ensure product reliability but also facilitate safe, scalable manufacturing.
You will learn;
How design and engineering principles matter for healthcare specific products
Designing for easy manufacturability… that can scale
Designing for reliability— assessing potential failure points
Thinking about regulatory standards
How Design and Engineering Principles Matter for Healthcare-Specific Products
In medical device development, design and engineering principles are not just important—they are essential. Getting the design right is like building a strong foundation for a house. If that foundation is shaky, everything else is at risk. In healthcare, where lives are on the line, the stakes couldn’t be higher.
One of the primary considerations is user-centered design (something I will talk about in detail next week). This involves understanding the specific needs of anyone who will interact with the device— patients, healthcare professionals, caregivers, etc. You want to design something that;
Solves the problem
Intuitive and easy to use
Less prone to user errors
Minimum amount of training
Safe and efficacious
Once these design considerations are ready to be translated into a product, engineering principles come into play. The structural beams of this foundation, they ensure that the materials, electronics, and software all come together in a way that’s safe, reliable, and functional.
Electrical Components:
Using established safety standards and components, understanding the power requirements of your device and maintaining signal integrity are essential starting points, in the conception, phase as well as while planning for manufacturing.
In 2019, Edwards LifeSciences had to recall their inpatient blood pressure/pulse monitoring systems for a faulty power outlet where fluid leakage could cause them to short circuit and explode, thereby increasing the risk of fires in an environment that is full of oxygen tanks and other gases that can catastrophic!
Mechanical Components:
This control requires selecting materials that are robust and easily sourced, while also keeping the number of mechanical components to a minimum. You need to think about how the over-all assembly can be calibrated for precise functioning, while also keeping in mind the maintenance component. Having easily replaceable/repair-able parts increases the life of your device while also maintaining function.
In a 2014 recall, the Philips Respironics ventilator had a component that failed to provide mechanical breaths to patients, thereby risking lives. They came across the problem when production testing, but thousands of devices were already in hospitals, however no deaths/injuries were reported.
Software Components:
When designing software for healthcare, using an intuitive, minimal user friendly design is key in adaptability. Healthcare workers use several clinical software throughout the day and you don’t want to add to their cognitive load by creating complex applications. Software that integrates with existing system, allows exchange of data easily while maintaining privacy is key. Almost 90% of hospitals have experienced at least one data breach incident between 2016-2021, with 24% of all cyberattacks being in healthcare.
In 2018, Medtronic had to recall their Minimed Insulin Pumps due to a software security breach that could give hackers access to the remote controller that manages the delivery of the insulin. Since the remote controller was an optional component, Medtronic only had to recall that part and not the whole pump.While the additional remote controller might have seemed like a great new feature, it certainly created more problems.
Inadequate attention to these principles lead to design failures, and risk human lives. These device failure examples underline the importance of integrating sound engineering practices from the very beginning of the design/conceptualization process.
Designing for Manufacturability
So, you’ve got a great design. Now’s the tricky part—scaling it up so that it can be manufactured consistently and reliably, over hundreds of batches. This is where Design for Manufacturing (DFM) comes into play.
It starts with simplified designs—think about using standard parts that are easy to procure and assemble. This not only cuts costs but also makes the entire process smoother. By standardizing components and creating interchangeable modules, you can keep things consistent across different product models, which is a huge win for production and future expenses.
Next one is assembly efficiency. The goal here is to minimize the use of specialized tooling necessary for production and make the design as automation-friendly as possible. By integrating multiple functions into single components, you reduce the number of parts, which speeds up assembly and reduces labor costs. It also reduces the potential number of failure points.
Choosing the right materials is also crucial. It’s about finding that sweet spot between cost, performance, and durability. And having reliable suppliers and backup sources keeps the production line moving smoothly, even if something goes wrong.
Finally, think about scalability. Your manufacturing process should be flexible enough to scale up or down as needed. In the end, the goal is to create a product that’s not only high-quality but also easy and cost-effective to produce on a large scale. And, if needed (like the COVID pandemic), you should be able to ramp down production with minimum time and resources.
One of the most important steps here is testing the manufacturing process itself. You need to prototype and refine your manufacturing process, conduct quality control analysis. This helps catch any issues before you start large scale production.
Designing for Reliability: Building a Trustworthy Product
Reliability is like the glue that makes or breaks a device. It’s what ensures that your medical device will perform as expected, day in and day out, without fail.
To build reliability into your design, you need to think ahead and identify potential failure points. Tools like Failure Modes and Effects Analysis (FMEA) are critical here. They help you anticipate where things might go wrong so you can address these issues before they ever reach the patient… ideally, BEFORE they leave your warehouse!
Redundancy is another critical aspect. Think of it as having a backup plan. By incorporating backup systems, your device can keep operating even if a component fails. Additionally, designing fail-safe mechanisms ensures that if something does go wrong, it doesn’t lead to catastrophic consequences.
Stress testing is like putting your device through boot camp. You need to test it under extreme conditions—like high temperatures, humidity, cyclic testing and vibration—to make sure it can withstand real-world use. Lifetime testing helps predict how long your product will last and identify any potential weak points.
Finally, quality is non-negotiable. Implementing a Quality Management System (QMS) compliant with ISO 13485 ensures consistent product quality. Don’t forget document control—keeping detailed records of all design, manufacturing, and testing processes is crucial for accountability and continuous improvement and to traceback the development and improvement.
Thinking About Regulatory Standards: The Rulebook You Must Follow
Navigating the regulatory landscape for your device early on, helps you understand the rules of the game. These are standards set by bodies like the FDA or the European CE marking to ensure safety of patients and an effective device development system.
It sounds like a headache (and often is, in a good way), but incorporating these standards into your design from the beginning saves you time and frustration down the line. Plus, it’s not just about checking boxes; it’s about ensuring your product is safe, effective, and ready to make a positive impact on patients’ lives.
This means conducting thorough risk assessments, keeping meticulous documentation, and making sure your device meets all the necessary pre-market approval standards. Remember, the regulatory landscape is constantly evolving, so staying up-to-date is crucial. More on this in my next issue…
Wrapping It Up
Designing a medical device that can be reliably manufactured at scale is a bit like cooking up a complex recipe—you need the right ingredients, the right tools, and a clear understanding of the process from start to finish. By focusing on user needs, designing for manufacturability, ensuring reliability, and adhering to regulatory standards, you can build a product that not only works but works well on a large scale.
Thank you for reading and stay tuned for more about developing your next medical product!
Keep Innovating,