The difference between fully-automatic and semi-automatic AEDs

Automated External Defibrillators (AEDs) can be the difference between life and death for someone experiencing sudden cardiac arrest. AEDs are portable devices designed to deliver an electric shock to the heart in case of sudden cardiac arrest. Most AED suppliers offer fully automatic and semi-automatic AEDs, but what is the difference? With the information provided here, you can understand the differences between fully automatic and semi-automatic AEDs, allowing you to make an informed decision when selecting the best option for your needs.

Understanding the difference in shock delivery between fully automatic and semi-automatic AEDs

The difference between fully automatic and semi-automatic AEDs lies in how they deliver the shock. When the AED detects a shockable rhythm, it begins charging to prepare for shock delivery. A fully automatic AED will deliver the shock automatically and indicate completion. With a semi-automatic AED, the rescuer has to manually administer the shock by pressing the flashing shock button. Understanding this distinction is essential in selecting the suitable AED for emergencies.

The fully automatic in the left photo only has the green on-off button, the semi-automatic in the right photo also has the orange shock button in addition.

Advantages and disadvantages

Both fully automatic and semi-automatic AEDs have their advantages and disadvantages. The benefit of a fully automatic AED is its ease of use, making it a good choice for inexperienced users or public areas. It's important to consider the safety of shock delivery with fully automatic AEDs, as they may deliver the shock without the rescuer checking that nobody has physical contact with the victim. In contrast, semi-automatic AEDs allow rescuers to quickly check for obstructions and ensure the victim's safety before manually administering the shock.

Choosing between a fully automatic or semi-automatic AED

Based on our experience in ambulance rescue, we recommend considering a semi-automatic AED for the following reasons:

  • Familiarity: A semi-automatic is a popular choice for CPR and AED training. This familiarity can help the rescuer feel more confident using the device during an emergency.
  • Safety: Before administering the shock, the rescuer can manually check that no one has physical contact with the victim, which can prevent injury to both the victim and the rescuer.
  • Availability and Cost: Semi-automatic AEDs are more commonly available on the market and are generally slightly cheaper. 

While fully automatic AEDs have the advantage of requiring less manual action, it is important to consider the potential safety risks associated with automatic shock delivery. Ultimately, the decision between a fully automatic or semi-automatic AED will depend on the specific needs and circumstances of the intended user and location.