Page 220 - Safety Risk Management for Medical Devices

Production and Postproduction Monitoring 199

Each of the above answers would be counted as one instance in each of the five
severity classes. Let’s imagine that in a dataset of 97 hypoglycemia events we have the
following counts:

• Catastrophic: 0
• Critical: 2
• Serious: 20
• Minor: 25
• Negligible: 50

P 2 is agnostic of the Hazardous Situation. That means we want to know, for all
reported cases of hypoglycemia regardless of the Hazardous Situation that caused it,
what were the outcomes. So, if two different Hazardous Situations could cause hypo-
glycemia, we aggregate all the hypoglycemia cases together.
Continuing with our example, the total cases of hypoglycemia were: 97.
Therefore for the Harm of hypoglycemia P 2 numbers are:

• P 2 (Catastrophic): 0/97 5 0%
• P 2 (Critical): 2/97 5 2.1%
• P 2 (Serious): 20/97 5 20.6%
• P 2 (Minor): 25/97 5 25.8%
• P 2 (Negligible): 50/97 5 51.5%

To ensure effective feedback loops from postmarket to preproduction risk manage-
ment, it is advisable that the responsibility for maintaining the risk management file
be defined and assigned to specific staff.

24.4 BENEFITS OF POSTMARKET SURVEILLANCE

Clearly patient/user safety is enhanced by active surveillance of production and postpro-
duction information about marketed products. But the manufacturer also receives signifi-
cant benefit from the surveillance, namely, the opportunity to quickly identify and rectify
product/process defects. This in turn leads into reduced customer complaints, reduced field
corrective actions, improved reputation and customer loyalty, which means higher sales.
And if that’s not enough motivation, failure to perform product surveillance could result in
substantial fines, criminal prosecutions, seizure of product, and closure of the business.
Another benefit of postmarket surveillance is about the clinical Hazards list (CHL)
(see Section 11.5). The CHL is an invaluable tool of risk management. The CHL is
claimed to be complete, at any given time. The basis of that claim is that the CHL is
a living document, containing the best available knowledge at any given time. And, if
any new Hazards are discovered, they are added to the CHL. Without postmarket
surveillance data, we cannot make the claim of completeness.