Diagnostics & Imaging Week

The FDA's Center for Devices and Radiological Health has issued a new document outlining a program for bolstering its post-market surveillance of medical devices, with the document, at the same time, outlining a variety of rather high barriers that it terms "special challenges" for doing so.

Overall, the report emphasizes that CDRH "must shift to a culture that places more emphasis on the importance of our post-market efforts and on collaboration in identifying and solving post-market problems, both within the center and with outside constituencies."

The effort in improving post-market surveillance is obviously needed, according to the report itself.

One of the appendices to the report (Appendix B, "Epidemiologic Aspects of Postmarket Medical Device Safety") says that "the rates reported for medical devices have been comparable to those for drugs" – noting this statistic simply as "interesting."

It is extremely interesting indeed, since it puts this statistic in the context of the Institute of Medicine (Washington) report, To Err is Human, which estimated the deaths from adverse drug events at nearly 100,000 a year in U.S. hospitals.

And in the same appendix, it is noted that CDRH funded a one-year study of visits to emergency departments, with the study finding that "in a one-year period, 452,000 visits to emergency departments were for injuries associated with medical devices. Of these, 58,000 patients died there or were hospitalized." (The percentage of those who died and those hospitalized was not stated.)

In general, the report in a variety of ways focuses on the extensive under-reporting of adverse medical events associated with the use of medical devices.

To address this issue, the document says that, based on a 2005 study of its postmarket safety programs, it will seek to develop a "culture of collaboration" for improving these programs within the center, including the development of "world-class data sources and systems" for identification and dissemination of adverse events and problems with medical devices and radiation-emitting systems.

It says that a senior-level team made up of "CDRH management and outside consultants experienced in medical device safety and product regulation will help guide the center in this effort." It does not provide a timeline for when this team will be established or when it will report results.

Others that it indicates the center will pursue collaboration with in this effort include "already existing advisory panels," "medical and other professional societies" and "joint efforts among center components."

And the document promises broader dissemination of safety problems and improved "coordination, consistency, quality and timeliness" of compliance and enforcement.

Besides outlining the general goals of the "shift" to greater post-market surveillance and how this might be done, the document offers an interesting roundup of difficulties in monitoring the safety of medical devices already being marketed:

  • It notes that the detection of problems is difficult – especially in the case of rare events – because of what it terms the broad under-reporting of adverse events by device users.
  • CDRH, it says, receives "tens of thousands" of reports concerning adverse events each year but that a preponderance provide only "sketchy information" about how the device was used and details about the actual cause of the problem. "This makes it difficult to assess the nature of the problem, and to distinguish between separate problems that may affect the same device."
  • Healthcare providers "generally do not document device use in patient records," therefore making it difficult to determine the device used that resulted in the adverse event. "Devices lack unique identifiers, and manufacturers continually produce modified versions of their products. And device firms are often purchased by other companies, which compounds the problem of product identification. As a result, identifying information about the device often does not appear in large databases."
  • Off-label uses of a device make it hard "to determine whether an observed problem is inherent in the device, or whether it resulted from inappropriate use."
  • And the document also notes a "gradual shift" in the use of medical devices into patients' homes, so that devices are being used by non-professionals and thus producing "another element of uncertainty" in ascertaining the exact problem and the best solutions.

The problem of precisely documenting adverse events with use of devices, even when they are reported, is also noted throughout the report.

Thus, as part of the new program's data gathering efforts, CDRH said it "will champion the development of a system to provide unique device identification, a standardized and globally accepted nomenclature for devices, and mechanisms and incentives for device users to include this information in healthcare records."

It added: "We will work to develop an electronic reporting system, so that all postmarked information is available to all who need to use it."

And the above-noted appendix cites three requirements needed for accurate documentation of adverse device events in order to provide the necessary epidemiological studies:

  • "A rational system of codes for devices, such as the Unique Device Identifiers being developed in conjunction with the Global medical Device Nomenclature."
  • "Routine documentation in patient records of device use and device-related problems."
  • "If the device codes are placed on devices and device users recognize that the code describes the device, using the code in documentation and reporting will enhance communication of which device is being described."

Besides outlining steps for making the improvement in post-market assessment and surveillance, the document, titled "Ensuring the Safety of Marketed Medical Devices: CDRH's Medical Device Postmarket Safety Program," is intended to provide information concerning the ability of CDRH to do effective post-market surveillance under the Medical Device User Fee Act of 2002, it says, "if MDUFMA is reauthorized."