Synchronized Cardioversion

ALS Defibrillator Functions
(Part 3 - Synchronized Cardioverson)

ALS Defibrillator = Advanced Life Support Defibrillator
Defibrillators used by medical providers. Typically by EMS and in advanced care settings Hospitals, Free standing ER's, etc.

A lot of medical providers are uncomfortable using the ALS Defibrillator in their medical care settings. This is largely due to the lack of training and the variety of brands and models on the market. This often leads to intimidation and delay in treatment.

Therefore, this series highlights the main features of the ALS Defibrillator. We want to get you thinking about and looking at your facilities defibrillator……NOW……and not during an emergency. Hopefully, this helps boost your confidence!

4 Part series will include:

Part 1: Using AED Mode for Defibrillation

Part 2: Using Pacing Mode for Transcutaneous Pacing (TCP)

Part 3: Synchronized Cardioversion

Part 4: Manual Mode for Defibrillation

Steps for Synchronized Cardioversion

General steps for Cardioversion:

Apply pads and 3 leads to patient. There is currently 1 set of pads on the market, made by ZOLL, that has a 3 lead built into the pad and does NOT require the additional 3 lead cable. They are called One Step Complete with One Step Pacing. View their informational handout.

Turn on defibrillator

Check your lead view. You can view the rhythm from Pads, Lead I, Lead II, or Lead III. Pick the lead view that gives the clearest picture of the QRS as this is what the defibrillator will use to determine where to shock.

Press the Sync button. After you press sync – you should see triangles above the R wave and the word sync somewhere on the defibrillator.

Adjust the number of Joules 

Charge the defibrillator

Press and hold shock

Watch the video walking you through these steps. Additionally, the pictures below will show where to locate the sync & lead select buttons on various defibrillators.

Video demonstrating steps

Where to find the lead view & sync buttons.

Pictures of some of the most common ALS defibrillators: ZOLL, LIFEPAK, and PHILLIPS with guidance on where to locate the cardioversion functions. 

Blue will show you where to turn on the defibrillator.

Pink will show you where to find the Lead Select button and where it tells what lead it is showing.

Yellow will show you how to turn on the sync function and where to verify that sync mode is on. 


While several models of ZOLL Defibrillators are on the market they have similar visual features. 


While several models of LIFEPAK Defibrillators are on the market they have similar visual features. 


These pictured Phillips Defibrillators were commonly seen in the hospital setting. They have been discontinued and no longer being supported by PHILLIPS. They are included in this blog as some hospitals still have them for use. 

My understanding, is the only ALS defibrillator that they will be making is the prehospital care Tempus ALS.

They will still be manufacturing AED’s for the community setting. 


Hope you enjoyed the post and found it helpful.
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