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Accuracy of instructional diagrams for automated external defibrillator pad positioning
Alexander G Foster1, Charles D Deakin2
1Faculty of Medicine, University of Southampton, Southampton, SO17 1BJ, UK.
Introduction:
Correct defibrillation pad positioning optimises the chances of successful defibrillation. AEDs have pictoral representation to guide untrained bystanders in correct pad positioning. There is a wide variation in this pictoral guidance and evidence suggests that correct anatomical pad placement is poor. We reviewed all currently available diagrams and assessed the resultant pad placement achieved by untrained bystanders following these instructions.
Methods:
Twenty untrained bystanders were presented with a total of 27 different pad placement diagrams (including one designed by the researchers) in a random sequence and were asked to apply them to the chest of an adult manikin. The lateral/medial and cranial/caudal position in relation to the optimal position recommended by the European Resuscitation Council guidelines was then measured for each pair of pads.
Results:
Overall, the sternal pad was placed an average of 6.0 mm cranial to, and 3.2 mm medial to, the optimal position. The apical pad was placed an average of 78.2 mm caudal to, and 59.3 mm medial to, the optimal position. The pad position diagram we designed and assessed out performed existing diagrams.
Conclusion:
All current defibrillation pad diagrams fail to achieve accurate defibrillation pad placement. A clearer, more effective diagram, such as the one we designed, is urgently needed to ensure bystander defibrillation is effective as possible.
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