Influence of electromagnetic fields on function of automated external defibrillators.
OBJECTIVE
In this study, the authors tested whether electromagnetic interference (EMI) is able to impair correct electrocardiogram analysis and produce false-positive shock advice from automated external defibrillators (AEDs) when the true rhythm is sinus.


METHODS
Nineteen healthy subjects were used to test five AEDs available on the Austrian market in a prospective, open, and sequence-randomized study. The primary outcome variable was the absolute number of shocks advised in the presence of EMI. The secondary outcome was the number of impaired analyses caused by incorrectly detected patient movements or electrode failure.


RESULTS
Of 760 tests run, 18 (2.37%) cases of false-positive results occurred, and two of five AEDs recommended shocks in the presence of sinus rhythm. Of 760 tests run, no electrode failures occurred. There were 27 occurrences (3.55%) of motion detected by an AED in the presence of strong electromagnetic fields.


CONCLUSIONS
AED models differ in their response to EMI; it may be useful to consider specific safety requirements for areas with such fields present. Working personnel and emergency medical services staff should be informed about potential risks and the possible need for patient evacuation before AEDs are attached and shock recommendations are followed.
Fleischhackl
Roman
R
Department of Emergency Medicine, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna, Austria. roman.fleischhackl@meduniwien.ac.at
Singer
Florian
F
Nitsche
Wolfgang
W
Gamperl
Guenther
G
Roessler
Bernhard
B
Arrich
Jasmin
J
Fleischhackl
Sabine
S
Losert
Heidrun
H
Sterz
Fritz
F
Mittlboeck
Martina
M
Hoerauf
Klaus
K
D000328:Adult; D004554:Electric Countershock / Q000295:instrumentation*; D004562:Electrocardiography / Q000295:instrumentation*; D004574:Electromagnetic Fields; D019544:Equipment Failure Analysis; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D008297:Male; D009068:Movement; D011187:Posture; D011336:Probability; D011446:Prospective Studies; D012016:Reference Values