What this page is not
It is not a certification, a protocol, or a substitute for a class. Cardiac arrest is not something anyone performs well the first time from memory of an article, and the gap between having read this and having practiced on a manikin is large enough that it changes outcomes. A basic CPR and AED course takes a few hours, costs little or nothing, and is offered constantly. If you take one thing from this page, take that.
What a page like this can usefully do is remove the reasons people freeze. The two most common are not knowing whether to start and worrying about being blamed afterward. Both are addressable, and both are addressed below.
Call 911 first
When someone collapses and does not respond, the first action is getting emergency medical services moving, because everything a bystander does is a bridge to them arriving. If you are alone with an adult who has collapsed, call 911 yourself, put the phone on speaker, and start. If there are other people, do not shout at the crowd — everyone assumes someone else will act. Point at one person and give them one job: "You, in the green jacket, call 911 and tell them where we are." Point at another and send them for the nearest AED.
Stay on the line. The dispatcher is trained to coach bystander CPR and will tell you what to do, count a rhythm for you, and keep you steady. Following a dispatcher beats following a memory. Know the address you are at, since that is the question people go blank on.
Hands-only CPR for an adult who collapses
For an untrained adult bystander helping an adult who suddenly collapses, current public guidance is hands-only CPR: chest compressions alone, no rescue breaths. Two reasons. Interrupting compressions to attempt breaths reduces blood flow, and reluctance about mouth-to-mouth was leading people to do nothing at all. Doing nothing is far worse than compressions alone.
| Step | What it looks like |
|---|---|
| Check | Tap the shoulder, shout. No response and no normal breathing means act. Gasping is not breathing |
| Call | 911 on speaker, or point at a specific person and send them |
| Position | Person flat on their back on a firm surface, you kneeling beside the chest |
| Hands | Heel of one hand in the center of the chest, other hand on top, fingers interlaced |
| Push | Arms straight, shoulders over hands, push hard and fast — about two inches deep, 100 to 120 per minute |
| Release | Let the chest come all the way back up between pushes. Incomplete recoil is a common error |
| Continue | Until they respond and breathe normally, an AED is ready, or EMS takes over. Swap every couple of minutes if someone else is there |
Two things people get wrong. The first is stopping because they are not sure the person is really in arrest — the guidance is to start when there is no response and no normal breathing, because irregular gasping in the first minutes looks like breathing and is not. The second is pushing too gently. Proper compressions are hard work, and it is common for ribs to crack; that is an expected consequence of effective CPR on someone whose heart has stopped, not a reason to ease off.
The AED does the deciding
An automated external defibrillator is designed for people with no training. Turn it on and it talks you through everything: it tells you where to place the pads, it analyzes the rhythm itself, and it will only deliver a shock if the rhythm is one a shock can treat. It will not shock a heart that should not be shocked. That is the whole reason these devices are mounted in airports, gyms, schools and offices rather than locked away.
Practical points: expose the bare chest and dry it if wet, place the pads as the pictures on them show, make sure nobody is touching the person while it analyzes or shocks, and resume compressions immediately after a shock. Leave the pads on. If the unit has a pediatric setting or pediatric pads and the patient is a young child, use them, but an adult AED used on a child is better than no AED at all. Notice where the AED is in the buildings you spend time in, because the search is the part that costs minutes.
Children and infants are different
Pediatric and infant resuscitation is not the adult sequence scaled down. The compression technique, the depth, the hand or finger placement, and the balance between compressions and breaths all differ, and children in arrest more often got there through a breathing problem, which changes what helps. Those numbers and techniques belong in a hands-on class where you practice them on an infant manikin, and this page deliberately does not list them.
What is worth knowing now: a child who collapses still needs 911 immediately, and a dispatcher will coach you through pediatric CPR over the phone in real time. Choking is also handled differently in infants than in adults, and again that is a class. If you have small children in the house, a pediatric CPR and first aid course is a few hours well spent, and it also covers the household hazards worth removing.
Common first aid, and the mistakes that make it worse
| Situation | Helps | Makes it worse |
|---|---|---|
| Burn | Cool running water for several minutes, remove rings and watches early, cover loosely with a clean dressing | Ice directly on the burn, butter or ointments, popping blisters, pulling off stuck clothing |
| Bleeding | Firm direct pressure with a clean cloth, add layers on top, keep pressing | Lifting the cloth to check, pulling out an embedded object |
| Suspected broken bone | Keep it still and supported, ice over cloth, get it seen | Trying to straighten it, pushing bone back, making them walk on it |
| Seizure | Clear hard objects away, cushion the head, note the time, roll them on their side once it stops | Putting anything in the mouth, holding them down, giving food or drink |
| Nosebleed | Lean slightly forward, pinch the soft part of the nose for ten unbroken minutes | Tipping the head back, packing tissue deep into the nostril |
| Choking adult | If they can cough or speak, encourage coughing; if they cannot, act and get 911 called | Blind finger sweeps, slapping the back of someone who is coughing effectively |
Burns that cover a large area, or involve the face, hands, feet, genitals or a joint, or come from electricity or chemicals, need medical care regardless of how they look. A seizure lasting more than about five minutes, or repeating without recovery in between, is a 911 call. If someone was in a fire, smoke inhalation matters as much as visible burns — see the home fire safety guide for the escape side of that. Heat illness has its own rules, and the one that matters is that a confused person is a 911 call, covered in the heat wave guide.
The fear of being blamed
Every US state has some form of Good Samaritan law protecting people who voluntarily help in an emergency, and the general shape is consistent: someone acting in good faith, within what a reasonable untrained person would do, is protected from liability for the outcome. The details differ by state and nothing here is legal advice, but the practical reality is that bystanders who perform CPR are not the ones who end up in trouble. Calling 911 and staying on the line also leaves a record of what you did and why.
So the useful takeaway is short. When an adult collapses and is not responding or breathing normally, call 911 or send someone to, then push hard and fast in the center of the chest and do not stop. Send someone for an AED and let it make the decisions. And then, on some ordinary weekend when nothing is happening, sign up for the class — because the difference between a person who has read this and a person who has done it once on a manikin is the difference that shows up in the room.
Questions people ask
Does reading this mean I can perform CPR?
No, and it is worth being blunt about it. Background reading reduces hesitation and tells you what the first move is, but competence comes from a few hours of hands-on practice with an instructor and a manikin, where you find out how hard compressions actually are and how quickly you tire. CPR and AED classes are run constantly by the Red Cross, the American Heart Association, hospitals and many fire departments, they take an afternoon, and they cost little or nothing. If you take one action after reading this page, book one.
Do I have to give rescue breaths?
If you are an untrained bystander and an adult has collapsed in front of you, current public guidance is hands-only CPR: compressions alone, no rescue breaths. Pausing to attempt breaths interrupts blood flow, and hesitation about mouth-to-mouth was causing people to do nothing at all, which is by far the worst outcome. Push hard and fast in the center of the chest and keep going until help arrives or the person starts breathing normally. Rescue breathing is taught in a certified class, along with the situations where it matters more.
Can I hurt someone by using an AED wrongly?
An AED is built to be used by people with no training. You turn it on and it gives voice instructions for everything, including where to put the pads. It analyzes the heart rhythm itself and will only allow a shock when the rhythm is one that a shock can treat, so it will not shock a heart that should not be shocked. Make sure nobody is touching the person during analysis or shock, place the pads on bare dry skin as the diagrams show, and go straight back to compressions afterward.
Is CPR the same for a child or a baby?
No. Compression technique, depth, hand or finger placement, and the role of rescue breathing all differ for children and infants, and pediatric arrest more often begins with a breathing problem, which changes the approach. Those specifics belong in a hands-on pediatric class rather than in an article, which is why they are not listed here. In the moment, call 911 immediately — the dispatcher can coach you through pediatric CPR on the phone in real time. If small children are in your household, a pediatric CPR and first aid course is a few hours well spent.