The Heart-Aid was developed to follow the ABC protocol of CPR assessment that was common in the 1970’s and 1980’s and included some additional safety measures that many of the defibrillators used by professional rescue personnel did not have.

THE ABCs:

Airway: This unit had a Oropharyngeal airway, a.k.a. OPA, (essentially a devise that would be pushed through the mouth down the throat of the patient) with an electric sensor and microphone on it.  It was thought that if the patient is responsive they would gag on the electrode and no further steps needed to be performed immediately.  If the devise was accepted into the upper airway the small microphone would pick up breathing sounds and, if detected, the machine would not operate further. Lastly, circulation was measured by a small computer chip that would detect the heart’s electrical activity between the OPA and the electrode placed on the upper abdomen of the patient and determine, independently, if a shock was needed.

As the Heart-Aid was developed for the non-professional to operate a design innovation made its debut – the sticky electrode pad, which is common on all AED devises today. It was determined that the shock paddles were too intimidating for an average bystander to use and so Heart-Aid used a sticky pad with the electrode embedded so that the operator could place and move away, increasing operator comfort and safety.

The last innovation was that of the human voice instructions that would tell the operator a step by step procedure to ensure the defibrillator was used correctly.  This allowed anyone who understood English and had the ability to follow the directions to use the devise in the event of an emergency.  Today AEDs also have pictures and can be programed in multiple languages, increasing its usability in public settings.

Further information about AED development and the Heart-Aid brand here:

https://emergencycare.hsi.com/blog/the-history-of-treating-sudden-cardiac-arrest