Multi-shock accessory device

A system, comprising:

• a defibrillator comprising:
• a first treatment circuit comprising a first capacitor configured to discharge a primary electrical shock to first electrodes configured to be disposed on skin of a subject;
• and
• a first processor configured to:
• determine that a multi-shock accessory device is coupled with the defibrillator;
• and
• in response to determining that the multi-shock accessory device is coupled with the defibrillator, cause a multi-shock instruction to be provided to the multi-shock accessory device, the multi-shock instruction indicating a time interval between the primary electrical shock and a secondary electrical shock;
• and
• the multi-shock accessory device comprising:
• a housing configured to removably couple the multi-shock accessory device with the defibrillator;
• a second treatment circuit comprising a second capacitor configured to discharge a secondary electrical shock to the subject;
• and
• a second processor configured to:
• receive, from the defibrillator, the multi-shock instruction;
• and
• in response to receiving the multi-shock instruction, cause the second treatment circuit to discharge the second capacitor to output the secondary electrical shock to second electrodes configured to be disposed on the skin of the subject, the secondary electrical shock being temporally overlapping with the primary electrical shock.