TSEAC
July 17 & 18, 2003
TOPIC #3
Questions for the TSEAC Panel:
1.
What
information in the published literature should be viewed as supportive data to
establish methods and procedures for reprocessing medical devices potentially
contaminated with TSE?
2.
Data in the published scientific literature or
developed from in-house studies with a specific medical device may not be
applicable to other medical devices.
For example, differences in device
fabrication material, device design, methods for cleaning, or changes in device
intended use may alter the effectiveness of a TSE inactivation procedure.
a.
Please
discuss which aspects of a medical device and its use should be considered when
determining whether a new TSE inactivation study might be needed for a specific
device?
b.
Please provide guidance on how these aspects of a
medical device should be included in the TSE inactivation study design.
3.
What
criteria should be considered when analyzing the results of TSE inactivation
studies? For example, is log reduction
of TSE infectivity, (expressed as), an appropriate endpoint for such
studies?
a.
If
so, what magnitude of log reduction in LD50 would be considered safe?
b.
Are
there other endpoints, such as the presence of PrPres that would be acceptable
surrogate markers for infectivity?
4.
The
extent of TSE inactivation required for any reprocessing procedure depends on
the amount of infectious agent present
in/on the device.
a.
Considering the scientific
literature describing the level of infectious material present in different
human tissues, please discuss what amounts of infectious material may be
present on contaminated medical devices.
b.
Please provide guidance on how
the level of infectious material on a medical device should be considered when
designing and interpreting a TSE inactivation study.
Questions for the TSEAC Panel:
1.What
information in the published literature should be viewed as supportive data to validate the methods and
procedures for reprocessing medical devices potentially contaminated with TSE?
1.
a.What elements (e.g.
the material used for device fabrication, device
design, method for cleaning, intended use) should be considered in designing a validation study to demonstrate
that a reprocessed medical device contaminated or potentially contaminated with
a TSE agent is safe for reuse?
1.
1.Medical devices potentially exposed to TSE can
include surgical instruments such as scalpels, neuro burrs, neuro drill bits,
neural electrodes, endoscopic devices, sterilizers and accessories such as
sterilization trays. These medical
devices are available in several different sizes, design configurations, and
materials.
Please
discuss the factors to consider when determining whether a validated
reprocessing method can be applied to any given device. When will additional validation
studies be needed for a specific device design?
1. 4. What criteria should be
considered when analyzing the results of such studies? For
example is log reduction of the TSE
infectivity, expressed as LD50, an appropriate endpoint for
such methods? If so, what magnitude of log reduction would be considered
safe? Are there other endpoints, such
as the presence of PrPres that would be acceptable surrogate markers for infectivity?
5. The extent of TSE inactivation required for any reprocessing
procedure depends on the amount
of infectious agent present in the device.
Please discuss
the current scientific information which describes the level of
infectious material found in different human tissues and possibly the contaminated
medical devices.
Please discuss how this
information should be considered in designing the validation
studies.