Patent attributes
A wearable cardiac defibrillator (“WCD”) system may include a support structure that a patient can wear, an energy storage module that can store an electrical charge, and a discharge circuit that can discharge the electrical charge through the patient so as to shock him or her, while the patient is wearing the support structure. Embodiments may actively take into account bystanders, both to protect them from an inadvertent shock, and also to enlist their help. In some embodiments the WCD system includes a speaker system that transmits a sound designed to assist a bystander to perform CPR. Optionally CPR chest compressions received by the patient can be further detected, and feedback can be given. In embodiments, a WCD system may include a user interface that can be controlled to output CPR prompts tailored to a skill level of the bystander.