Scope
As a medical device manufacturer, it is essential to specify the lifetime of your medical device, and also the maintenance instructions for it. Given the absence of a precise definition of device lifetime, Team NB has released a paper on medical device lifetime so as to provide consistency and guidance to manufacturers.
Did You know that within EU MDR, there is no explicit definition for the “Medical Device Lifetime”? Nevertheless, as a component of the general safety and performance requirements (GSPR – Annex I of the MDR), the regulation mandates manufacturer obligations concerning the lifetime of the medical device. Which is why, on 15th December 2023, Team Notified Body released a paper to further clarify this important aspect for medical device manufacturers.
This article moves in the direction to provide an overview on this Team-NB position paper.
Manufacturers are advised to establish their lifetime specifications through prudent risk assessments, taking into account the seriousness and probability of device failures. Comprehensive pre-clinical tests, clinical evidence, and post-market follow-ups are vital for accurately determining a device’s lifetime. The service interval denotes maintenance frequency and should not be confused with the device’s total lifetime. To avoid confusion, manufacturers must clearly define the lifespan in terms of years of usage or the number of uses, backed by evidence to substantiate their decision.
The position paper covers different device types, including implantable, active, software, and biological devices, and emphasizes the importance of post-market surveillance and clinical data in determining device lifetime.
- Active Devices: Active devices have a typical device lifetime specified in years, aligning with the reasonable risk associated with failure modes and their severity. Manufacturers employ various analyses to ensure safe and effective use, including evaluating device characteristics, conducting component/material analyses, and performing statistical determinations. Maintenance activities are determined throughout the device’s lifecycle, considering usability and verification/validation processes. The post-market phase involves ongoing monitoring and evaluation, including clinical follow-up duration for endpoints. Manufacturers must make residual risks and device lifetime information available to users through the device instructions for use.
- Software Devices: For medical device software (MDSW), manufacturers are required to provide a statement regarding the device’s lifetime and outline plans for managing various aspects, including software changes, end-of-life considerations for operating systems or tools, updates to software components, and maintenance of security and compatibility. Manufacturers must also ensure that the device remains safe for its intended use, including when incorporating artificial intelligence algorithms, and demonstrate ongoing awareness of technological advancements relevant to the software’s functionality. All residual risks and the device’s lifetime information should be accessible to users through the device’s instructions for use.
- Implantable device: Implantable devices, which are surgically implanted within the body, necessitate safety considerations for the entire duration of their implantation, extending beyond stated performance specifications. Key analyses for ensuring safe and effective use include evaluating device characteristics, conducting component/material analysis, and assessing pre-clinical data such as functional testing and biocompatibility. Considerations also include the power source lifetime for active implantable medical devices, usability throughout the intended lifetime, and post-market monitoring for clinical endpoints. Residual risks and device lifetime information must be provided to users through the device instructions for use.
- Biological Devices: Biological devices, which may include medicinal products or exhibit pharmacological, immunological, or metabolic actions, require special consideration for device performance lifetime. These devices may involve substances or materials that persist in the body until removal via absorption or excretion.
The typical device lifetime is determined based on reasonable risk for failure modes and severity. Key analyses for safe and effective use involve evaluating device characteristics, rate of action and absorption, determination of functional lifetime, mechanical integrity, and risk-benefit assessments. Manufacturers should mitigate risks as much as possible and provide users with residual risks and device lifetime information through instructions for use.
Team-NB recommendations include:
- Manufacturers must define the device’s lifetime or expected service life in technical documentation, ensuring it’s accessible to users through instructions for use. The definition should cover all pertinent device characteristics, ensuring safe and effective use over the device’s lifecycle and in line with current regulatory standards.
- Unlimited or undefined lifetimes are not feasible. Manufacturers must quantify lifetimes in terms of years, usage, or operational periods according to relevant standards. Functional testing should be conducted based on typical usage scenarios.
- Device lifetime should be integrated into design inputs and verification processes, especially for non-legacy devices. Verification should account for normal use conditions, single fault safety, and foreseeable misuse.
- Clinical data, including post-market surveillance and follow-up activities, can support the device’s lifetime. Performance and safety must remain consistent throughout the expected lifetime, maintaining a positive benefit-risk profile.
- In the absence of clinical data, literature reviews or PMCF studies may suffice. Pre-clinical evaluations should cover aspects like absorption rates and safety impact.
- Manufacturers can justify their device-specific testing methods during conformity assessment, considering risk severity, likelihood, and state-of-the-art technologies. Durations of safety and effectiveness, including body presence, should be accounted for.
Conclusion
Regulations and guidance define medical device lifetime in terms of safe and effective use, which varies by device type. Manufacturers should specify lifetimes based on reasonable risk, supported by pre-clinical testing and clinical data, including PMCF studies. Service intervals should not be confused with device lifetimes, which may extend to decommissioning or removal.
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