Device Design Modifications Informed by In Vitro Testing of Bacterial Attachment Reduce Infection Rates of Cochlear...

Area of Science:

• Biomedical Engineering
• Infectious Diseases
• Medical Device Design

Background:

• Implanted medical device infections are often caused by biofilms, driving antibiotic use and resistance.
• Reducing device-associated infections can improve antibiotic stewardship and patient morbidity.
• Cochlear implants, while successful, can be explanted due to intractable infections.

Purpose of the Study:

• To determine if implantable medical device design modifications reducing bacterial attachment impact device-associated infection rates.
• To investigate bacterial accumulation on Cochlear™ Nucleus^® CI24RE™ devices.
• To assess the clinical impact of design changes on infection incidence.

Main Methods:

• In vitro bacterial attachment assays and examination of explanted devices identified bacterial accumulation features.
• Macro-scale design modifications were incorporated into CI500™ and Profile™ series Nucleus implants.
• Mandatory post-market vigilance data from 198,757 CI24RE and 123,084 CI500/Profile implantations were analyzed.

Main Results:

• Design modifications aimed at reducing bacterial attachment were identified.
• These design changes correlated with significantly reduced infection rates in clinical practice.
• A reduction in device-associated infections was observed post-modification.

Conclusions:

• A design-centric approach mitigating bacterial attachment effectively reduces infections in Cochlear Nucleus devices.
• This strategy offers a simple and effective means to lower device-associated infections.
• The findings are likely applicable to improving the design of other implantable medical devices.