FDA notified healthcare professionals that it is investigating energy levels in external biphasic defibrillators with shocks of less than or equal to 200 Joules (J). FDA received reports of 14 events since 2006 in which a 200 J biphasic defibrillator was ineffective in providing defibrillation/cardioversion therapy to a patient, whereas a subsequent shock from a different 360 J biphasic defibrillator resulted in immediate defibrillation/cardioversion. The majority of events occurred during attempts at cardioversion of atrial fibrillation, but there was at least one instance with defibrillation of a ventricular arrhythmia as well. Analysis of the 14 cases does not suggest the need for any change to current clinical practice, and as FDA continues its evaluation of this situation, providers are encouraged to follow the American Heart Association's guidelines/algorithms for treatment of cardiac arrhythmias, and to follow manufacturers' instructions for using defibrillators.
FDA is seeking additional information in order to interpret the significance of these events, and to determine whether FDA activities are advised. If you suspect a problem with a defibrillator, such as a situation where a patient received shocks from multiple devices, the problem should be reported to the FDA'sMedWatch Safety Information and Adverse Event Reporting Program online (atwww.fda.gov/MedWatch/report.htm,) by phone 800/332-1088, or by returning the postage-paid FDA form 3500 (which may be downloaded from the MedWatch"Download Forms" page) by mail (to address on the pre-addressed form) or fax (800/FDA-0178.)
[11/05/2009 --http://www.fda.gov/MedicalDevices/Safety/AlertsandNotices/ucm189259.htm-- FDA]