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ABCs versus CAB

Does it really make a difference?

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In 2015, when CPR and first aid guidelines were last reviewed,
the ABCs were (in certain cases) modified in an effort to increase the speed
and effectiveness of CPR and related care.

Understanding the ABCs and CAB of CPR is key to understanding techniques
such as compression-only "CPR" and important priorities that make all
the difference when seconds count.

The most significant change enacted by the Emergency Cardiac Care (ECC) Committee 

of the American Heart Association consists of rearranging

the ABCs to CAB for victims of Sudden Cardiac Arrest (SCA).

According to Sudden Cardiac Arrest Association, Sudden Cardiac Arrest
is the leading cause of death in the United States. SCA claims more than
325,000 lives each year.
During a Sudden Cardiac Arrest, heart function ceases, abruptly and without warning. 

When this occurs, the heart is no longer able to pump blood to the rest of the body 

which keeps the vital organs alive. 

Death occurs in 95% of victims.

Adults typically collapse (or go down) because of Cardiac issues.
Children typically go down because of Respiratory issues.

The Chain of Survival in both cases would be -
- ABCDE for hypoxic victims (lack of Oxygen)
- CABDE for victims (who you witness) suddenly collapse (Cardiac Arrest)

The "ABCs" refer to "Airway, Breathing, Circulation".

A - Open the airway and make sure it is clear.
B - Look, Listen and Feel for Breathing. If not found, give 2 breaths.
C - Check for Circulation (the Carotid pulse in the neck).
S - Check for Spinal Injury
S - Check for Severe Bleeding

CAB refers to "Compressions, Airway, Breathing"

C - Compressions. If there is no severe bleeding begin 30 chest compressions.
A - Open the Airway and make sure it is clear.
B - Look Listen and Feel for Breathing. If not, give 2 breaths.

How CAB Works

The change is designed to get compressions started as quickly as possible
for victims that have oxygenated blood.
Think about it. 

The patient was breathing until the moment of collapse.

The heart stopped due to an electrical problem, not a lack of oxygen.
Giving compressions immediately starts the oxygen-rich blood moving
through the body, delivering oxygen to the brain and other vital organs.
Taking time to give breaths delays the care the victim really needs.

How Compression-Only "CPR" Works

CAB also explains why compression-only "CPR" works for a short period of time.
Since the patient has oxygen in his system, performing compression immediately 

is a more critical care step.

A recent study published in the New England Journal of Medicine showed
no significant difference between the survival outcomes of patients 

given compression-only "CPR" and standard CPR.

Compression-only "CPR" is easier to perform, especially for bystanders without protective breathing devices.

When Do We Use the ABCs?

The ABCs should still be followed for victims who are hypoxic (without oxygen). 

This includes the majority of children, infants and cases of respiratory issues

which can then lead to cardiac arrest due to oxygen depletion.

Take a drowning victim for example.
This begins as suffocation in water, but the heart usually keeps beating until
the oxygen in the blood is used up. 

That is when cardiac arrest occurs.

This victim needs ventilations first and then compressions if the heart stops (standard ABC CPR).
Giving compression first, or compressions only, to this victim may not be effective 

due to lack of oxygen in the bloodstream.

When Do We Use CAB?

CAB is used when you witness a victim collapse due to a Cardiac issue.
When the heart's electrical system stops working properly, the heart cannot
send the oxygenated blood to the brain and other organs to keep them alive.
Some of the causes of Sudden Cardiac Arrest include Electrocution, 

Sudden Trauma to the heart or to the brain, a Drug Overdose or Chemical Poisoning

to name but a few.

What are D and E in the Chain of Survival (ABCDE)?

D - Defibrillation, using an Automated External Defibrillator (AED)
An AED stops the heart for a moment, hoping the heart starts again
in a regular sinus rhythm.
You can add a D to either the ABCs or CAB for a more comprehensive solution.

E - Emergency Medical Services
As soon as you see someone suddenly collapse, EMS should be called.

Does using the ABCs or CAB really matter?

Time and getting EMS on scene as soon as possible does save lives.

You now have a better understanding of the differences between the two

and the effects of both.

However, in a Medical Emergency, when you are in Adrenaline Rush Mode

and trying to remember all the training you have taken, you may forget.

The important thing to remember is to get the professionals there as soon as possible, 

if the victim is not breathing, breath for him, and if the heart is not working, you need perform compressions.

Do your best until the professionals get there and take over.

By doing CPR (and using an AED if available), you can help Save a Life!

Contact us at to schedule a class.

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