One of the most popular—and one of the most essential—techniques in emergency medicine is cardiopulmonary resuscitation, more commonly known as CPR. First developed in 1960, CPR involves a series of chest compressions and recovery breaths to patients suffering from cardiac arrest. Its primary function is to restore the flow of oxygenated blood to an individual’s brain and heart in order to delay tissue death and brain damage in the event of an effective resuscitation.

Contrary to popular belief, CPR alone is unlikely to restart a patient’s heart, but patients who do receive CPR are significantly more likely to be successfully resuscitated. Because of its potential to save lives, everyone should have at least a basic understanding of CPR.

Identifying Cardiac Arrest

Time is muscle during heart attacks or episodes of cardiac arrest, and therefore, it’s critical to be able to identify the signs so you can react as quickly as possible. Typical signs of a heart attack or cardiac arrest include sudden collapse or loss of consciousness; discomfort in the chest or in other areas of the upper body, including the jaw, neck, back, or stomach; shortness of breath or cessation of breath altogether; nausea; lightheadedness; cold sweat; and other symptoms.

Alternatively, if you encounter an unconscious person, try to shake them and ask, “Are you OK?” You may also want to check their pulse or breathing. If they remain unconscious, if they aren’t breathing, or if they don’t have a pulse, then you should begin CPR.

Get Help and Check the Scene (Assuming the Scene is Safe)

In any situation where you need to provide emergency medicine, your first move should always be to call 9-1-1 so that paramedics will head to the scene. Additionally, before you begin CPR or other emergency care, make sure that the scene is safe. You don’t want to risk further harm to the patient or to yourself by remaining in a dangerous area such as a busy road or underneath a structure that could collapse on you, for example.

Begin Compressions

Once you’ve assessed the patient and checked to see that the scene is safe, then it’s time to begin administering CPR. Have the patient lie flat on their back and lift their chin in the air so that their airway remains open. Then, place your hands on top of each other in the center of their chest and press down by about two inches at a rate of 100 compressions per minute (to the tune of the Bee Gees’ “Stayin’ Alive”). You can use your bodyweight to help you deliver these compressions.

Give Rescue Breaths

After the first set of 100 compressions, give the patient rescue breaths. Their head should be tilted slightly to open the airway, and following that, you should pinch their nose shut and place your mouth over theirs to form a complete seal. Then, blow into their mouth twice, and continue compressions.

Continue compressions and breaths until paramedics arrive, until you are no longer able to do so without hurting yourself, or unless the scene becomes unsafe. Additionally, if an automated external defibrillator (AED) is available, then you can follow the instructions provided and use it to help resuscitate the patient.