Biomedical Engineering Reference
12.2 PMS and Its Role in Design
As stated earlier, all medical device companies must have an active postmarket surveillance
system in place. Some think this is only to capture complaints; it is not. The PMS is to capture
information about your device after it has hit the marketplace, be that good, bad, or indifferent.
It is common, therefore, to have a three-pronged attack. The first prong is to have a clinical lead
looking at the clinical literature and knowledge base. The second prong is to have the marketing
manager collect all information from your sales and marketing staff, and current market
literature. The third prong lies with the technical director whose job it is to collect all quality
related information and material from the technical knowledge base. The trick is bringing all
three prongs into one outcome. Hence all three strands need examining for every one of your
main products with a view to coming out with one of the following design outcomes:
This can only happen if you discuss all three inputs relative to your device. This need not be
every week but it should be more than once a year! A further input is, of course, the
emergency input for a design modification - the dreaded Preventative Action Notice. 1
Figure 12.1 illustrates a typical PMS meeting procedure. The three main areas - technical, market,
and clinical - would collect data and bring that data to the meeting. The meeting would then
discuss the data to decide which of the three outcomes is the most appropriate. The hard part of
this procedure is to ensure that everyone collects the data and does not leave it to the day before!
In this section I intend to illustrate some tools that may be of use in your PMS. It is impossible
to present all possible tools but these are ones I think are pertinent and easily adopted.
12.3.1 Process Control Chart
This is probably one of the oldest tools around. Primarily it exists to capture slowly changing
parameters before they grow into parametric defects. I have already presented to you the
need for continual evaluation of your products; this is a simple extension of that process.
For example, you have a product and deemed it necessary to randomly inspect samples from
every batch. You could simply file that inspection report with the batch documentation and
from thence it will only see the light of day if it is ever the subject of an audit. Or you could
use it as a part of your continual improvement process by passing the information onwards.
1 A preventative action leading to a design modification would be called if there is a design fault that can be
rectified quickly without the need for a recall.