Every minute matters when someone's heart stops beating. Cardiac arrest can happen anywhere, to anyone, at any time, and the person nearest to the victim is often an ordinary bystander, not a trained medical professional. Knowing how to perform CPR correctly can mean the difference between life and death before emergency services arrive.
This guide walks you through each stage of the CPR process in clear, sequential order, covering adult CPR using the standards set by the American Heart Association. Whether you are a healthcare professional refreshing your skills, an employer preparing your team, or a community member who wants to be ready in an emergency, these steps will give you a reliable framework to follow.
By the end of this guide, you will know how to assess the scene, call for help, open the airway, deliver effective chest compressions, and use an AED if one is available. You will also understand when to keep going, when to stop, and how formal CPR certification builds on everything covered here.
One important note before we begin: this guide is educational and intended to supplement, not replace, hands-on CPR training from a certified instructor. Practicing on a mannequin under qualified supervision is the only way to develop the muscle memory and confidence needed to act quickly in a real emergency. If you have not yet completed a certified course, consider enrolling in one after reading through these steps.
Let's get into what you need to know.
Step 1: Assess the Scene and Check for Responsiveness
Before you do anything else, stop and look around. Rushing to a victim without checking your surroundings can turn one emergency into two. Scan the environment for hazards such as traffic, downed electrical wires, fire, unstable surfaces, or any other threat that could put you at risk. You cannot help anyone if you become a victim yourself.
Approach only when the scene is safe. Once you reach the person, tap them firmly on both shoulders and shout clearly: "Are you okay?" Do this loudly enough that someone who is dazed or disoriented would hear you. If there is no response, that is your first critical signal.
Next, look for normal breathing. Watch the chest rise and fall for no more than 10 seconds. This is an important distinction: gasping or agonal breathing, which sounds like irregular, labored gulping, does not count as normal breathing. It is a common reflex in the early moments after cardiac arrest and should not delay your response.
If the person is unresponsive and not breathing normally, they need CPR immediately. Do not second-guess yourself. The window for effective intervention narrows with every passing second, and acting imperfectly is far better than not acting at all.
Common pitfall: Many bystanders spend too long trying to confirm unresponsiveness. Do not check for breathing for more than 10 seconds. Every moment of delay reduces the chance of survival.
Success indicator: You have confirmed the person is unresponsive and not breathing normally. You are ready to move to the next step.
Step 2: Call 911 and Get an AED
The moment you determine someone needs CPR, help needs to be on the way. Shout for help immediately and, critically, direct a specific person rather than calling out to the crowd in general. Point at someone and say something like, "You in the blue jacket, call 911 right now." This counters a well-documented psychological phenomenon called the bystander effect, where individuals in a group each assume someone else will take action, and as a result, no one does.
If you are alone with an adult victim, call 911 yourself before starting CPR. Put the call on speaker so you can follow dispatcher instructions while keeping your hands free. Dispatchers are trained to guide callers through CPR in real time, so keep the line open throughout.
The rules shift slightly for pediatric emergencies. If you are alone with a child or infant, perform two minutes of CPR first before stopping to call 911. This is because cardiac arrest in children is more often caused by respiratory failure, making those first two minutes of CPR especially critical before you pause for anything else.
At the same time, send a second bystander to locate and retrieve the nearest AED. Most public buildings, schools, gyms, airports, and workplaces are required to have one on the premises. AEDs are designed to be used by ordinary people and will walk you through the process with audio and visual prompts. Getting it to the scene quickly matters enormously.
Success indicator: 911 has been notified, an AED is being retrieved, and you are ready to begin hands-on care.
Step 3: Position the Victim and Open the Airway
If the person is not already on their back, carefully roll them over. Support the head and neck as you do this, and move them as a single unit if possible. Place them on a firm, flat surface. This detail matters more than people realize: a soft mattress or couch will absorb much of the force from your compressions, significantly reducing their effectiveness.
Kneel beside the victim at chest level. This position gives you the best mechanical advantage for delivering compressions and allows you to monitor the chest for breathing and rise during rescue breaths.
Now open the airway using the head-tilt chin-lift technique. Place one hand on the person's forehead and gently tilt the head back. With two fingers of your other hand, lift the chin upward. This movement straightens the airway and prevents the tongue from blocking it, which is one of the most common reasons an airway becomes obstructed in an unconscious person.
If you have reason to suspect a spinal injury, such as after a fall, diving accident, or vehicle collision, use the jaw-thrust maneuver instead. Push the jaw forward by placing your fingers behind the angles of the jawbone and lifting, without tilting the neck. Protecting the spine takes priority in these situations.
Before moving on, take a quick look inside the mouth. If you can clearly see an object blocking the airway, remove it. Never perform a blind finger sweep, reaching into the mouth without being able to see what you are doing can push the obstruction deeper.
Success indicator: The airway is open, the head is tilted back, and the chin is lifted. You are ready to begin compressions.
Step 4: Deliver Chest Compressions
This is the most critical skill in CPR. Effective chest compressions manually circulate blood to the brain and vital organs, buying time until the heart can be restarted. Quality matters here: depth, rate, and recoil all affect how well compressions work.
Start by finding the right hand placement. Place the heel of one hand on the center of the chest, directly on the lower half of the breastbone. Place your other hand on top and interlace your fingers. Keep your fingers lifted off the chest so that only the heel of your bottom hand is making contact.
Straighten your arms and position your shoulders directly above your hands. This alignment lets you use your body weight to drive compressions rather than relying solely on arm strength, which fatigues quickly and leads to shallow compressions.
Push down at least 2 inches deep for adult victims. The American Heart Association recommends a depth of at least 2 inches but no more than 2.4 inches. Compress at a rate of 100 to 120 compressions per minute. If you need a mental reference, the beat of the Bee Gees song "Stayin' Alive" falls right in this range and is a commonly used mnemonic in CPR training.
After each compression, allow the chest to fully recoil back to its natural position before pressing down again. Do not lean on the chest between compressions. Full recoil allows the heart to refill with blood, which is what makes the next compression effective. Without it, you are circulating progressively less blood with each push.
Minimize interruptions. Any pause in compressions should last no longer than 10 seconds. Every time you stop, blood flow drops to near zero and takes several compressions to rebuild.
Common pitfall: Many people do not compress deeply enough, often out of concern about causing injury. Rib injuries, while possible, are far less serious than the alternative. Effective compressions require firm, deliberate pressure. Do not hold back.
Success indicator: You are maintaining a steady rhythm at the correct depth and rate, and you are allowing full chest recoil between each compression without leaning on the chest.
Step 5: Give Rescue Breaths When Trained and Appropriate
If you are trained in CPR and willing to give rescue breaths, follow a 30:2 ratio: 30 chest compressions followed by 2 rescue breaths. After completing 30 compressions, re-open the airway using the head-tilt chin-lift technique.
Pinch the nose shut with your thumb and index finger. Create a complete seal over the person's mouth with your own. Give a breath lasting approximately one second while watching for the chest to rise. If the chest rises visibly, the breath was effective. Give the second breath the same way, then return immediately to compressions.
If the chest does not rise on the first breath, reposition the head to ensure the airway is fully open and try once more. If the second attempt also fails to produce chest rise, return to compressions without further delay. Do not spend excessive time troubleshooting the airway at the expense of circulation.
Here is something worth knowing: if you are untrained, unwilling, or uncomfortable giving rescue breaths, Hands-Only CPR using continuous compressions without rescue breaths is still highly effective for adult victims of sudden cardiac arrest. The American Heart Association recognizes Hands-Only CPR as a valid response for adults precisely because the blood already in the body contains enough oxygen to sustain circulation for several minutes of compressions alone.
For infants and children, the situation is different. Pediatric cardiac arrests are more commonly caused by respiratory failure than by a primary cardiac event, which means rescue breaths carry greater importance in those cases. If you are ever in a situation involving a child or infant, prioritize getting rescue breaths in from the start.
Success indicator: Each rescue breath produces visible chest rise without over-inflating the lungs, and you are returning to compressions promptly after each set of two breaths.
Step 6: Use an AED as Soon as It Arrives
The moment an AED reaches the scene, use it. Do not wait. Early defibrillation is one of the most important factors in survival from cardiac arrest, and every minute without it reduces the odds of a successful outcome.
Turn the AED on immediately. Most modern devices power on when you open the lid or press a clearly marked button, and they will guide you through every step with audio instructions and visual prompts. You do not need to memorize a sequence. Follow the device's directions.
Attach the pads to bare skin. One pad goes below the right collarbone. The other goes on the left side of the chest, below the armpit. Each pad has a diagram printed on it showing exactly where it should be placed. If the person's chest is wet, dry it quickly before applying the pads. If they have a hairy chest, many AED kits include a razor for this purpose.
Before the AED analyzes the heart rhythm, make sure no one is touching the victim. Stand clear yourself, and announce loudly: "Everyone stand clear." Any contact during analysis can interfere with the reading.
If the AED advises a shock, ensure everyone is still clear, then press the shock button immediately. Resume CPR right away after the shock, starting with compressions. Do not pause to check for a pulse. If the AED advises no shock is needed, resume CPR immediately. The device will re-analyze the rhythm every two minutes and prompt you accordingly.
Leave the pads attached and the device on throughout the entire resuscitation. Do not remove the AED or turn it off. Let it guide you until emergency responders arrive and take over.
Success indicator: The AED is attached, the analysis is complete, and you have either delivered a shock or confirmed that no shock is needed and resumed compressions without delay.
Step 7: Continue CPR Until Help Arrives or the Victim Recovers
CPR is a sustained effort. Once you start, keep going. Continue cycles of compressions and rescue breaths until one of three things happens: emergency medical services arrive and take over, the victim shows obvious signs of life such as breathing normally or moving purposefully, or you are physically unable to continue.
Fatigue is a real factor. Compression quality degrades quickly as the muscles tire, and shallow compressions are far less effective than deep ones. If other bystanders are present, rotate the role of compressor every two minutes. This keeps compression quality high and ensures the person receiving CPR has the best possible chance. The person stepping in should take over immediately at the end of a compression cycle without any unnecessary pause.
Do not stop to check for a pulse during CPR unless the victim shows clear signs of recovery. Checking for a pulse is difficult even for trained professionals, and unnecessary pauses reduce blood flow to the brain.
When EMS arrives, give them a clear and brief handoff. Tell them when the person collapsed, how long CPR has been in progress, whether an AED was used, and whether a shock was delivered. This information helps the arriving team make fast, informed decisions.
After the emergency is over, take care of yourself. Performing CPR on another person, especially someone you know, can be emotionally intense. It is completely normal to feel shaken, distressed, or overwhelmed afterward. Debriefing with a mental health professional or a peer support group is encouraged and is nothing to be ashamed of.
Success indicator: You maintained continuous, high-quality CPR until a qualified provider took over or the situation clearly resolved.
Putting It All Together: Your CPR Readiness Checklist
Performing CPR correctly comes down to seven clear actions: assess the scene, call for help, open the airway, deliver compressions, give rescue breaths when appropriate, use an AED, and keep going until help arrives. Reading through these steps builds awareness, but true readiness comes from hands-on practice.
A certified CPR course gives you the opportunity to work through these steps on a mannequin, receive real-time feedback from a qualified instructor, and build the muscle memory that kicks in during a real emergency. At Midwest CPR Center, we offer a range of courses designed for every level, from community members taking their first Heartsaver CPR AED class to healthcare professionals completing BLS Provider or ACLS certification. Our certified instructors create a supportive, practical learning environment so you leave confident and prepared.
Use this quick checklist as a reference:
Scene safety confirmed before approaching the victim.
911 called and AED requested as soon as unresponsiveness is confirmed.
Victim positioned on a firm, flat surface with the airway open using head-tilt chin-lift.
Compressions delivered at least 2 inches deep at a rate of 100 to 120 per minute with full chest recoil.
Rescue breaths given in a 30:2 ratio if you are trained and willing, or Hands-Only CPR continued if not.
AED attached and used as soon as the device arrives on scene.
CPR continued without unnecessary interruption until EMS takes over.
Don't wait until an emergency happens to equip yourself with these skills. Schedule your CPR certification class now and gain the confidence to respond when every second counts.