Medical devices: hygienic design combats pathogens

Medical hygiene does not just play a key role during the COVID-19 pandemic. Preventing the transmission of infectious diseases and especially the spread of multidrug-resistant organisms is paramount even in non-pandemic times. While hygiene practices in hospitals and medical offices are essential, the industry can also make an important contribution with hygienic product design.

During the virtual.MEDICA 2020, Dr. Sebastian Buhl’s lecture highlighted the hygienic design of medical devices at the MEDICA TECH FORUM. In this MEDICA-tradefair.com interview, he describes the aspects of this design and reveals how it can be implemented.

What exactly is "hygienic design" as it pertains to medical devices?

Dr. Sebastian Buhl: Hygienic design of medical devices essentially means that they are easier to clean or the risk of contamination is reduced. There is an emphasis on material choices and constructive design details and solutions. The material should be suited for surface treatments and preferably also be resistant to commonly used disinfectants.

Since there are no specifications for medical devices, detailed solutions usually adopt other standards such as food safety and hygiene standards. It is important to avoid problems such as sharp edges, cracks, and crevices. To assist in this endeavor, we are currently collaborating with a VDI task force on a sanity and hygienic design guide for these types of surfaces.

Which medical devices benefit the most from hygienic design?

Buhl: This design is critical wherever surface hygiene is crucial and clinically relevant pathogens often persist, subsequently creating a greater risk of contamination for patients or staff members. However, it is sometimes difficult to assess "hygienic relevance". Apart from the surface itself, the surface environment also plays an important role. A surface in a patient room on a general ward requires a different type of assessment than a surface in an intensive care or burn unit.

We are also collaborating with VDI to provide support in performing a standardized assessment or classification of hygienic relevance in our guidelines. In general, a hygienically optimized design is paramount for all medical devices that are at risk of infectious disease spread and consequently an increased risk of infection for patients or employees.

What are the available antimicrobial technologies today?

Buhl: Many antimicrobial surface coating technologies are already in use today. This year, our VDI task force published the "Antimicrobial Surfaces for Infection Prevention" status report, which gives a great overview on these types of surface technologies. A literature review that was conducted as part of the Anti-Microbial Coating Innovations to Prevent Infectious Diseases” (AMiCI) network has shown that about 30% of surfaces are silver-based systems, 17% use chitosan and 14% rely on titanium. Copper and zinc-based coatings are also an option. One must also differentiate between passive surfaces that prevent or limit the adhesion and the attachment of bacteria, and active surfaces that kill bacteria and viruses.

What will the future of hygienic design and antimicrobial technologies look like? What trends do you see in this setting?

Buhl: Thanks to the current pandemic situation, both users and manufacturers have shifted their focus on hygiene. We have come to realize that effective and efficient treatment of medical devices can play a big role in breaking the chain of infection. That is why hygienic design is more important than ever in the medical device planning stage, prompting some manufacturers to include hygiene experts or consulting firms in the development process.

We also noted an increasing demand for the hygiene assessment of medical devices. This is where antimicrobial surfaces come into play since many companies integrate them as an additional "hygiene feature" into their products. Having said that, one must always check whether the finished product still exhibits the promised antimicrobial activity. Sustainable optimized hygiene in the healthcare sector therefore requires lab, field, and benchmark testing to accurately evaluate the effectiveness of antimicrobial materials and agents, also as it relates to new sterilization and disinfection procedures.