CPR 101

Why Do We Do CPR?

The main reason to provide CPR is to restore the flow of oxygenated blood to the brain of a victim who has suffered sudden cardiac arrest. After SCA, the victim is not breathing (or not breathing adequately) and the heart is not pumping oxygenated blood to the brain or vital organs. Clinically the victim is dead. Biologically though, the victim still has a chance at survival.

After 4-6 minutes without oxygen, permanent brain damage will occur. After 10 minutes without oxygen the brain is dead, biological death has occurred. Biological death is irreversible. The reason we do CPR is to keep the brain alive after SCA by pumping blood to the brain with external chest compressions and rescue breaths.

History of CPR

The origins of CPR can be traced back almost 300 years when the Paris Academy of Sciences and the Society for Recovery of Drowned Persons in Amsterdam officially recommended mouth-to-mouth resuscitation for drowning victims. Other recommendations included warming the victim, positioning the head to let fluids drain, and manual pressure to the abdomen (along with some rectal or oral fumigation with tobacco and some bloodletting). Other pre-CPR techniques came along from different water-based clubs around the globe with names like the “Society for Resuscitating the Drowned” and the “Society for the Recovery of Persons Apparently Drowned.” These societies were able to significantly reduce drowning deaths in their areas with rudimentary techniques.

Unfortunately, not much occurred for about the next couple hundred years. In 1891, the first use of chest compressions was documented by Dr. Friederich Maass, and then in 1903 external chest compressions were used successfully by Dr. George Crile. A bit more recently though, the CPR we know today began to take shape.

In the 1950s, scientific proof was provided that mouth-to-mouth breathing is sufficient to maintain oxygenation because there is enough oxygen in our exhaled breath to keep someone alive. Dr. James Elam and Dr. Peter Safar went on to invent mouth-to-mouth resuscitation. In 1957, Peter Safar published, “The ABC of Resuscitation” which is said to be the foundation for public CPR training.

In 1960, CPR was formally developed. Physicians were trained with close-chest message and that became the beginnings of CPR training. Other notable CPR history includes:

• Late 19^th Century - The ‘Silvester Method’ is described by Dr. H.R. Silvester where an unresponsive victim is laid on his or her back, and the arms are raised above the head for inhalation and then pressed against the chest for expiration of breaths at a rate of 16 times per minute.
• 1911 - The Holder Nielson technique was described in the first edition of the Boy Scout Handbook which was very close to the Silvester Method but performed with the victim face down.
• 1966 - The National Research Council of the National Academy of Sciences convened an ad hoc conference to establish standards for teaching and performing CPR.
• 1981- Dispatcher CPR program was developed in King County, WA so that dispatchers could give CPR instructions over the phone. This is the standard now for all 9-1-1 call centers.
• 1983 - Development of pediatric resuscitation begins though an American Heart Association national conference.
• 1988 - First pediatric basic life support and advanced life support courses become available.
• 1990s - Public Access Defibrillation programs are developed to provide training and resources to the public to increase the odds of survival with early use of an AED by citizen rescuers.
• Late 1990’s to today - CPR conferences occur at an international level every five years where researchers discuss the latest science. CPR techniques are updated based on the best resuscitation science with one goal in mind – increased survival of cardiac arrest.

CPR Facts and Statistics

• In just one year, 436,000 Americans die from a cardiac arrest.
• 3 out of 4 cardiac arrests occur at home (73.4%), so it’s likely that if you know CPR you may save the life of a loved one.
• According to a report from the US Occupational Safety & Health Administration, about 10,000 cardiac arrests happen in the workplace in the U.S. each year.
• Only 40% of SCA victims receive bystander CPR.
• About 9% of people who suffer SCA outside of a hospital survive.
• CPR compressions are the most important part of CPR. Untrained rescuers or anyone who is unwilling or unable to give rescue breaths can compress the chest hard and fast in the center of the chest (at least 2 inches) and help save an adult’s life.
• Immediate CPR may double or triple the chance of survival from an out of hospital cardiac arrest.
• The sooner an AED is used the higher the chance of survival.
• A SCA victim’s chance of survival reduces by 7% to 10% every minute that an AED is not used.

What is CPR Certification?

CPR certification is when a potential rescuer takes a CPR course and passes both a written and skills test in front of a certified CPR instructor. CPR certification is catered to two types of audiences: healthcare providers/professional emergency responders and the community or workplace responder.

CPR techniques for healthcare workers are slightly different than those for community rescuers. Healthcare providers share the tasks of rescue breathing and chest compressions. They are taught how to use a bag mask ventilation device and for medical professionals, an assessment of the victim’s pulse is required to start compressions.

Community rescuers start CPR when the victim isn’t breathing, a pulse check is not taught to the lay provider and tasks such as compressions and breathing are not shared.

CPR is taught by an authorized instructor using lecture, demonstration, and video examples to convey the necessary skills. Blended learning courses where students do the classroom portion online then meet with an instructor to practice and test are an alternative option to traditional classroom-based courses.

Practice on a CPR manikin is required for certification. At the end of a certification course students must pass a written exam and a skills test to receive a certification card. CPR certification is usually valid for two years before it expires.

Where Do CPR Guidelines Come From?

CPR guidelines come from a wealth of international resources. The International Liaison Committee on Resuscitation (ILCOR) was formed in 1992 to provide a forum for communication between principal resuscitation organizations worldwide. Various CPR-related authorities gather and review research to identify what works to improve cardiac arrest outcomes.

Previously, CPR guidelines were updated every five years with the most favorable research and science. However, in 2015, this process transitioned to an online format that uses a continuous evidence evaluation process rather than periodic reviews. These continuously updated guidelines are used to develop new teaching materials and techniques for rescuers.

Current members of ILCOR include:

• American Heart Association (AHA)
• European Resuscitation Council (ERC)
• Heart & Stroke Foundation of Canada (HSFC)
• Australian and New Zealand Committee on Resuscitation (ANZCOR)
• Resuscitation Councils of Southern Africa (RSCA)
• Inter American Heart Foundation (IAHF)
• Resuscitation Council of Asia (RCA)

How To: Compression-Only CPR

Compression-only CPR, sometimes referred to as hands-only CPR, can be an effective alternative to conventional CPR for anyone unable or unwilling to perform rescue breaths. It’s easy to learn.

If a person collapses in front of you, after dialing 9-1-1 to ensure medical help is on the way, follow these CPR steps:

1. Place the heels of your hands on the center of the person’s chest.
2. Push hard and fast.

Continue giving compressions until trained CPR or emergency medical services providers take over, the automated external defibrillator (AED) directs you to stop while analyzing, or the person shows signs of life (e.g., responding by breathing, moving, or reacting).

Note that compression-only CPR isn’t appropriate or recommended for children and infants. Rescue breaths are extremely important for children and infants because cardiac arrest typically results from asphyxia (e.g., choking on foreign objects, drowning, etc.) rather than having cardiac issues.

Once a child is in cardiac arrest, their oxygen level is already severely depleted, making rescue breathing essential. However, if you’re unwilling or unable to give rescue breaths, performing compression-only CPR is better than no CPR.

The Tools of CPR

HSI offers a wide range of supplies necessary for the safe application of CPR. Visit our online store to find the items that best suit your needs:

• CPR Manikins
• CPR Masks
• AED
• Personal Protective Equipment (PPE)

CPR Masks & CPR Face Shields

CPR masks and CPR face shields protect rescuers from direct contact with a victim’s mouth during rescue breathing. The CPR face mask is a molded plastic mask. It typically comes in a clamshell case, requires quick assembly (snapping into the mask shape) and insertion of a one-way valve or filter. The face mask covers the victim’s mouth and nose. Pinching the nose is not needed with the use of a face mask. It prevents the backflow of air or fluids into the victim’s mouth.

Bag Mask

A bag mask is a specialized device used by medical professionals to assist with rescue breathing. It consists of a non-rebreathing mask, self-inflating bag and oxygen reservoir. The bag mask can be used with or without supplemental oxygen. During CPR, use of a bag mask requires special training and two rescuers; one rescuer does CPR and the other uses the bag mask to deliver rescue breaths after every 30^th compression (adult CPR).

To use the bag mask, the rescuer has to be positioned at the top of the victim’s head and squeeze the bag with one hand while simultaneously using the other hand to open the airway and seal the mask on the victim’s face. It’s not an easy skill to master. To become proficient at bag mask ventilation requires a lot of practice.

Automated External Defibrillator (AED)

An AED is a computerized device that provides a life saving shock to the heart during sudden cardiac arrest. An AED can dramatically increase a SCA victim’s odds for survival from less than 5% to as high as 50% to 70% (depending on the study). For every minute after SCA without a shock from a defibrillator, the victim loses about a 7-10% chance at survival.

The sooner an AED is used the more likely it will work. AEDs are easy to use. Simply oress the power button and follow the verbal prompts:

• Bare the victim’s chest
• Apply sticky pads (electrodes) that come with the AED to the victim’s bare chest. Pads have simple diagrams for placement.
• Press the shock button when prompted and after you’ve checked to see that no one is touching the victim.
• Resume CPR after the shock.

Remember that if an AED is not present, the sooner 9-1-1 is called the earlier professional rescuers will arrive with a defibrillator of their own.

Personal Protective Equipment (PPE)

PPE is used by community, workplace, and professional rescuers to protect against exposure to a victim’s blood or body fluids. During an emergency, rescuers may be exposed to blood or body fluid. If the victim has a bloodborne pathogen (disease causing microorganism such as HIV, Hepatitis B, Hepatitis C) there is a risk that coming into contact with their blood (or body fluid contaminated with blood) may cause a transmission of the disease from the victim to the rescuer.

PPE reduces the possibility of coming into contact with blood or body fluid, thereby reducing the risk of exposure. PPE for CPR includes:

• Goggles
• CPR barrier devices
• Gloves

Additional Sources

Circulation, Vol. 147, No.8, Heart Disease and Stroke Statistics—2023 Update

Circulation, Vol. 136, No.10, The Effects of Public Access Defibrillation on Survival After Out-of-Hospital Cardiac Arrest

Heart Disease and Stroke Statistics—2023 Update

International Liaison Committee on Resuscitation (ILCOR)