Ruggedising electronics for medical devices: Ensuring performance and reliability

In the healthcare industry, electronic devices play a crucial role in diagnostics, monitoring, and treatment. But they must be designed and assembled to perform in the most extreme conditions both inside and outside the human body. Here’s how.

Why ruggedisation matters in medical electronics?

Medical devices need to remain operational under the most extreme environmental and stresses of any sector. But they are also among some of the most delicate and highly calibrated equipment in use today.

What medical devices must be built to withstand:

• Extreme temperatures (both hot and cold)
• Exposure to moisture, liquids, and chemicals during insertion, cleaning and sterilisation processes
• Physical impacts from drops, collisions, or vibrations during transport
• Electromagnetic interference (EMI) in busy medical environments filled with other electronic devices

Given the high-stakes nature of medical care, ensuring that these devices remain functional under such conditions is crucial.  

Which is where the process of ruggedisation comes in.

Download our guide to outsourcing your medical device design and development

What are some key Strategies for ruggedising medical electronics?

Conformal coating for circuit protection

Conformal coating is one of the most effective ways to protect the delicate internal electronics of medical devices from environmental stress. This thin polymeric film conforms to the contours of the PCB (printed circuit board), shielding it from environmental contaminants such as moisture, dust, and chemicals. It prevents corrosion, ensures insulation, and enhances the overall durability of the electronics.

These coatings can also improve a device's resistance to temperature extremes and are particularly important for electronics used in environments where humidity, sterilisation fluids, or saline exposure are common. Conformal coatings typically include materials such as acrylics, silicones, and parylene, each offering unique protective properties tailored to specific medical applications.  They can be found protecting the electronic workings of implantable and wearable medical devices.

Hydrophilic vs. hydrophobic coatings

In addition to conformal coatings, specific hydrophilic and hydrophobic coatings play a significant role in protecting medical devices and enhancing their usability in wet environments.

How do they differ?

• Hydrophilic coatings are designed to attract and absorb water. These coatings create a lubricious surface that reduces friction, making them ideal for devices inserted into the body, such as catheters and guidewires. The low-friction surface allows these devices to move smoothly through bodily tissues, reducing patient discomfort and minimising tissue damage. Hydrophilic coatings are also beneficial for devices in cardiovascular, endoscopic, and neurovascular procedures where precision and ease of insertion are critical.
• Hydrophobic coatings, on the other hand, are highly relevant in the ruggedisation of electronics. These coatings repel water, preventing moisture from accumulating on the surface of medical devices, which could interfere with their functionality or lead to contamination. Hydrophobic coatings are particularly valuable for electronic medical devices exposed to cleaning agents, sterilisation processes, or bodily fluids. For instance, these coatings are applied to PCBs and sensors to protect them from moisture, ensuring the electronics remain operational even in humid or wet environments​.

Applications of hydrophobic coatings in medical electronics

• PCB Protection: Hydrophobic coatings shield the electronic circuits from moisture and condensation, reducing the risk of corrosion or short circuits.
• Displays and Touchscreens: In portable medical devices, hydrophobic coatings help keep displays clean and free from smudges or water droplets, which can obstruct visibility and touch functionality.
• Implantable Devices: Hydrophobic coatings prevent the accumulation of bodily fluids on devices like pacemakers or neurostimulators, ensuring they function reliably within the body.

Durability against physical impact

Medical devices are often transported and used in fast-paced environments, making them prone to drops and collisions. Designing devices with impact-resistant materials, such as reinforced plastics or metals, helps absorb shock and protect internal components from damage. Devices like portable patient monitors and handheld diagnostic tools benefit significantly from these design enhancements, which ensure they remain operational even after physical stress.

Thermal and EMI protection

Medical devices are frequently exposed to temperature fluctuations, whether in operating rooms or ambulances. To ensure stable performance, incorporating advanced thermal management solutions—such as heat sinks and thermal pads—is critical. These solutions protect sensitive electronics from overheating or condensation.

Additionally, EMI shielding is necessary to prevent electromagnetic interference from affecting device functionality. Hospitals often have many electronic devices operating simultaneously, and rugged medical electronics must include shielding technologies, such as conductive coatings or metallic enclosures, to prevent interference that could disrupt critical medical procedures.

Battery longevity and reliability

For portable devices, battery performance is essential. Ruggedised devices must have long-lasting batteries that operate reliably in fluctuating temperatures. Optimising battery life ensures that medical electronics, such as defibrillators or wearable devices, function during critical moments without the need for frequent recharging. Additionally, implementing battery backup systems provides redundancy in emergency situations.

Enhanced Usability and Compliance

While ruggedisation focuses on enhancing durability, it’s equally important to maintain usability. Medical devices must remain user-friendly despite being designed for durability. Buttons, touchscreens, and connectors must be easy to operate while still being protected from moisture, wear, and contamination.

Regulatory compliance 

Compliance is also crucial. Medical electronics must meet standards like ISO 13485 for quality management and IEC 60601 for electrical safety. Ensuring compliance while ruggedising devices requires close collaboration between designers and manufacturers to ensure that durability enhancements do not compromise regulatory approval.

Challenges in ruggedising medical electronics

Ruggedisation presents several challenges, particularly when balancing durability with usability and affordability. For example:

• Cost implications: Advanced protective materials and manufacturing processes can increase production costs, requiring careful trade-offs to ensure that ruggedisation does not make the device prohibitively expensive.
• Increased weight and bulk: Ruggedising often involves adding protective layers, which can make portable devices heavier and less ergonomic.
• User experience: Despite adding rugged features, it’s essential that medical devices remain easy to use by healthcare professionals, particularly in high-stress situations.

Conclusion

Ruggedising medical electronics is essential to ensure their reliability in challenging healthcare environments. From conformal coatings that protect circuitry to hydrophilic and hydrophobic coatings that enhance device functionality in wet environments, these strategies help protect devices from damage, ensure compliance, and improve patient outcomes.

By focusing on durability, usability, and compliance, manufacturers can create electronic medical devices that are not only rugged but also meet the needs of healthcare professionals and patients. 

Contract manufacturers with DfX and medical expertise can help optimise designs for the most demanding settings

Medical demand is accelerating even as costs escalate and technical challenges multiply.  As a result, it’s becoming more important than ever to find reliable contract manufacturers who have suitable certifications and experience to work in the medical device sector.  

And these were just the challenges the German company Carl Reiner faced, as they looked for help to design and manufacture their life-saving ventilators for use in surgery.   

Read our case study showing how ESCATEC helped them scale up the manufacture of durable and ultra-reliable electronic devices that could meet all the demands of the surgical environment.

For more information on Ruggedising electronics for medical devices: Ensuring performance and reliability talk to ESCATEC Mechatronics Ltd