Defibrillators Failing Too Early and Too Often

In a newly released white paper from the FDA detailing the "External Defibrillator Improvement Initiative", the following design and manufacturing practices were identified as examples of industry practices contributing to continued safety concerns that the FDA identified during its review of external defibrillators:

Engineering Design Practices.

Review of past recalls suggests that manufacturers of external defibrillators sometimes use design practices that lead to inconsistent device performance. In one example, a firm designed its voltage-monitoring circuit to draw power from the same power source it was intended to monitor. Because of this design, a momentary drop in the voltage caused a false signal to shut down the AED and the device was unable to deliver a shock, which may have caused a patient’s death. In another case, a firm used the wrong kind of component in one of the circuits, causing the device to be susceptible to interference from noise coming from the device’s power line. Good engineering design practices also require user interfaces (like dials, monitors, alarms, and connectors) meet users’ needs. Recent surveys suggest that improvements in user interfaces may be warranted.

Manufacturing Practices.

The FDA’s analysis of recalls and inspections identified problems in how manufacturers test and incorporate components used in the manufacture of external defibrillators, as well as how they evaluate changes to the device before they are implemented to assure that device modifications do not adversely impact the safety and effectiveness of the technology. Between 2005 and 2010, the FDA issued nine warning letters to external defibrillator manufacturers, seven of which cited the firms for failing to appropriately control these aspects of their manufacturing process.

In several cases, manufacturers purchased components from suppliers who did not meet the manufacturers’ required specifications. In some cases, the problem with the component was due to a change in how the component was manufactured by the supplier. However, it is the manufacturer’s responsibility to assure that the components it receives meet its specifications.

Design and Manufacturing are two key areas where DfR can help your company prevent problems! For more information, please contact Cheryl Tulkoff, ctulkoff@dfrsolutions.com.