Center for Devices and Radiological Health William Midgette A Perspective On Medical Device Risk Management Heart Rhythm Society Washington, D.C. September 16, 2005

Center for Devices and Radiological Health Two Common Approaches to Analyzing Risk u Bottom-up (inductive, e.g., Failure Mode and Effects Analysis) versus top-down (deductive, e.g. Fault Tree Analysis) u Bottom-up – induce a failure and determine the harm it can cause u Top-down – select an undesired top-level event and identify the faults that can cause it

Center for Devices and Radiological Health Fault-Tree Analysis u Requires the selection of an undesired top- level event, e.g, life-saving shock not delivered for an ICD u The analysis should identify all faults that can cause the event u Risk control measures should be included in the analysis

Center for Devices and Radiological Health Risk Control Measures u Protective measures, e.g. default operating modes u Information for safety, e.g., warnings in labeling u Many measures require intervention –The correct response for the circumstances, e.g. a patient-specific response –Timeliness

Center for Devices and Radiological Health Hazardous Situations u Circumstances in which people are exposed to a potential source of harm u Examples of ICD Hazardous Situations –Life-saving shock not delivered –Pacing therapy not delivered u Usually require a “system” of risk control measures

Center for Devices and Radiological Health Hazardous Situation and Causes Cause #1 Cause #2 Cause #3 Cause #4 OR Hazardous Situation

Center for Devices and Radiological Health Hazardous Situations, Causes, and Control Measures Cause #1 Cause #2 Cause #3 Cause #4 OR Hazardous Situation Control Measure #1 Fails Cntr.Msr. #2,#3.#4 Fails AND OR

Center for Devices and Radiological Health Simplified Example: Part of the Risk Control System for a Hazardous Situation OR Alarm Failure Sensor Failure No Intervention Incorrect Intervention Inadequate Training Confusing Instructions Air Embolism > 0.4mm Enters Blood Stream OR Dialysis System OR

Center for Devices and Radiological Health Simplified Example: Part of the Risk Control System for a Hazardous Situation OR Premature Battery Failure No Daily Battery Check By Patient No Intervention Untimely Intervention Poor Patient History Life-Saving Shock Not Delivered OR No Scheduled Appt. Limited Access To Emergency Care AND No AED Rural Home ICD

Center for Devices and Radiological Health Conclusions