Medical Devices
Useful articles:
Here is a list of interesting articles dealing with the reliability issues in medical devices. Be aware that it has not yet been proven that device malfunctions are due to soft error issues, as investigations are still under way. However, some environmental considerations lead to investigations of failure modes caused by radiations.
- IEEE 2008/Soft error reliability improvements for implantanble medical devices
- IEEE Special issue on medical electronics
- American heart Association article
- Daily News Central article
The problem/the issue:
While recalls in the cardiac rhythm device industry are not new, the sheer magnitude of potentially affected patients recently leads to a great deal of concern, frustration and even anger. Physicians are uncertain when (and if) to recommend device replacements in an environment where the magnitude of the risk and the potential consequences of device failure have not been well defined in a timely way. Several factors, including soft error from either cosmic rays, or local environment are responsible for these reliability issues.
By environment, one should understand that:
- Altitude and geographical location makes a difference on the aggressiveness of natural radiations.
- Hospitals for instance present a highly risky environment for patients, or employees, using Implantable devices like pacemakers. The following paper explains some of the risks.
Why should the problem be addressed?
According to the FDA (Food and Drug Administration), "Good Clinical Practices (GCP) refers to the regulations and requirements that must be complied with while conducting a clinical study. The primary regulations that govern the conduct of clinical studies are included in the Code of Federal Regulations, Title 21 (21 CFR)." Design control under 21 CFR § 820.30 requires that early in the design development process, design inputs or design requirements are identified. The design input should address topics such as user and patient needs, the intended use, performance characteristics, chemical and physical characteristics, safety, toxicity and biocompatibility, electromagnetic compatibility (EMC), reliability, regulatory requirements, historical data such as consumer complaints and MDRs, human factors, labeling and packaging, reliability, compatibility with accessories and auxiliary devices, compatibility with the environment of the intended use, risk analysis, voluntary standards, sterility, manufacturing processes, etc. A risk analysis is also mentioned in § 820.30. According to the FDA, design validation, conducting risk analysis early in the design process enables designers to identify unreasonable risks and work to reduce or eliminate them during the early phases of design development.
In light of all the recalls and modifications that happened in the past years on implantable devices, a proactive approach of assessing the risk of potential Soft Error threat and validating safe design becomes almost mandatory.
How can iRoC help?
As independent specialist of the topic, we offer a wide variety of solutions to run the risk assessment at the early design phase and validation in the pre marketing phase of the product. We can also run crash investigation program to give companies the best input so they can design the best recall strategy if needed. Please check our solutions here and contact us for specific questions.