Medical Device Design Service: 3 Factors to Consider

Effective and reliable medical device designs share similar characteristics - they address solution specifications,  end-user needs, and ergonomic considerations, while also complying with healthcare industry standards and regulations. Designing medical devices that add value to an end user’s experience while fulfilling a host of other regulatory requirements, however, isn’t an easy task. Medical device designers must take a systems approach to their designs in order to successfully integrate the complex functions and mechanisms of their new products.

The systems approach is especially important with medical devices because of the inherent potential risk they pose to the end-user. From design initiation to series production, careful planning and meticulous execution of that plan are required to bring a safe and successful product to market. This article will explain the formal definition of a medical device and serve as an introductory guide to the design and development of successful medical devices.

What exactly is a medical device?

According to the United States Federal Drug Administration (FDA), a medical device is  defined as any instrument, implant, apparatus, in-vitro reagent, machine, or any article that is intended for use in any of three main areas:

1. Diagnosis of diseases and various conditions.
2. Cure, treatment, mitigation, or prevention of diseases and various conditions in either humans or animals.
3. Altering the structure or function of a human or animal body without chemical or metabolic action (e.g. joint replacement hardware).

Any device that is labeled or used for any of these three functions is regulated as a medical device and is subject to FDA’s laws and regulations. For any devices that emit radiation, such as medical imaging devices, there are additional requirements.

Designing factors for medical devices

1. Identify design requirements

Perhaps the most important factors to consider when designing medical devices, before development work even begins, are 1) definition of the scope of the project, and 2) identification and definition of design requirements. Medical device projects that are poorly defined may fail to include important features, and risk not only failing to meet regulatory requirements but may also deliver inadequate solutions and care to end-users.

Designing medical devices that meet customer demands requires significant attention to detail. From the beginning, designers should have a clear understanding of what is expected of their developed product. Designers should be able to answer the following questions about the product itself before wading too deeply into the design process:

1. What is the intended use of this device?
2. What components are needed for this device to be successful?
3. Will this device be used in tandem with other devices?
4. Are there any specific performance targets?
5. What sorts of risks can this device pose to the end-user?
6. What gaps do you have in the current product performance, and what weaknesses of competitors you can potentially improve upon?
7. What is the target cost per piece?

Additionally, designers should consider human interface  factors of the design, such as, but not limited to:

1. Body measurements (e.g. height, hand width, organ size, arm length, etc.)
2. Health conditions of expected end-users (e.g. acute or chronic conditions)
3. Usability

Finally, designers should consider and be able to answer questions related to the environmental conditions for their device, such as:

1. What kind of environment will this device be used in? (e.g. a calm, hospital setting or a bumpy car ride?)
2. What kind of lighting will be present when this device is being used?
3. What’s the noise level in the environment?
4. What kinds of materials will this device come into contact with?

The points described here are not an all-encompassing list of items designers should consider. By identifying design requirements from the start of the development process and continually asking themselves throughout the process if those requirements are being met, designers can ensure that their devices are designed appropriately and successfully.

2. Design verification and validation

After a design is completed, but before moving to mass production, designers must first verify and validate that their designs work as intended and are manufacturable. The best way to do this is through computer modeling of the design (thermal, mechanical stresses, and any other important concerns) plus evaluating prototypes made by a rapid prototyping method. With a prototype in hand, designers can determine whether a design-intent part meets the customer’s requirements for functionality, usability, effectiveness, and reliability. They can identify unneeded or irrelevant features and focus their attention on more critical aspects of the design.

Additionally, designers must conduct risk management analyses. Through system failure modes and effects analysis, designers can determine the probability and severity of risks to the end user’s health from using the new device. For example, hazards can arise from toxic or flammable raw materials, malfunctions of mechanical or electronic features, or from devices that don’t deliver the intended performance (e.g. ineffective drug delivery, loss of control of life-sustaining functions). To ensure the best possible design and mitigate risks to the end-user, designers may need to conduct several cycles of product design, prototype build, testing, analysis, and redesign before proceeding to mass production.

3. Regulatory design compliance

Before a medical device is introduced into the market, it must first comply with certain regulations. Therefore, from the project to design a new device is initiated, designers should consider what regulations and standards apply to their new product. In the USA, medical devices are regulated by the FDA to ensure the safety and effectiveness of the devices.

Devices are classified into three categories based on risk: class I, II, and III, with devices in the highest classification having the most potential risk. Devices intended for human use, regardless of class, must submit a premarket notification 510(K) and apply for premarket approval (PMA) to the FDA which then clears the device for manufacture after it has been evaluated and deemed safe and effective. There are several other requirements for devices such as labeling and reporting requirements.

Keep the end-user in mind...

Designing medical devices can be a daunting task, but the most effective devices all share a similar trait - they comprehensively address end-user demands by delivering ergonomic solutions that comply with the appropriate regulations. From the start of the development process to the start of series production, and throughout the life cycle of the product, designers should take a systems approach to ensure that the best possible design is selected for your new medical device product offering. Contact an ACHB representative today to discuss how we can assist you with your medical device manufacturing needs.