CPR
8 steps, 100 to 120 compressions per minute, 30 compressions to 2 breaths.
Call 911 and start compressions before anything else. This page is reference material for candidates already in training and does not replace a hands-on CPR certification course.
Study material, not medical direction. This is reference material for candidates in training. On a real call, work to your service's protocols, your medical director's orders, and the certification you hold, not to anything you read here.
Overview
- Cardiac arrest is a rhythm problem, not a breathing problem: the single thing that keeps a brain alive until a defibrillator arrives is uninterrupted chest compressions.
- Compressions started immediately can double or triple survival, and quality drops measurably after about two minutes, so rescuers swap on that interval whenever a second rescuer is available.
- If you are untrained, unwilling to give breaths, or alone with no barrier device, do compression-only CPR. Compressions with no breaths beat hesitating.
- Rate
- 100 to 120 compressions per minute
- Depth
- at least 2 inches (5 cm), and no more than 2.4 inches (6 cm)
- Ratio
- 30 compressions to 2 breaths
Size up the scene
Confirm the scene is safe to enter before you touch the patient, and put on gloves and eye protection.
Key points
- A rescuer who becomes a second patient has made the call worse, not better. Traffic, fire, electricity and unstable structures come first.
- Note the time you found the patient; the downtime is one of the first things the arriving medic will ask you for.
Check for a response
Tap the patient firmly on the shoulder and shout. An adult who does not respond to that is unresponsive.
Key points
- Shout something specific rather than a general noise, so bystanders understand that you are assessing and not shaking a sleeping person.
- Do not spend time on this. A patient who does not answer the first firm prompt is not going to answer the fourth.
Call 911 and send for an AED
Activate emergency services and get a defibrillator moving toward you before you start compressions.
Key points
- Point at one person and give them the job by name or description. A general call to a crowd gets acted on by nobody.
- Alone with a phone, put it on speaker and start compressions while the dispatcher talks. Do not leave an adult to go looking for a phone.
Check breathing and pulse
Scan the chest and check a carotid pulse for no more than 10 seconds. No normal breathing and no definite pulse means start CPR.
Key points
- Agonal gasping is not breathing. It is common in the first minutes of arrest and it is the most frequent reason a bystander does not start compressions.
- If you are not certain you feel a pulse inside 10 seconds, you do not have one. Start compressions.
Set your hands and your posture
Heel of one hand on the center of the chest over the lower half of the breastbone, second hand on top, fingers interlaced and lifted off the ribs.
Key points
- Lock your elbows and stack your shoulders directly over your hands so the compression comes from your hips, not your arms. Arm compressions fade inside a minute.
- Get the patient onto a firm flat surface. A mattress absorbs most of the depth you think you are delivering.
Give 30 compressions
Push hard and fast: 100 to 120 compressions per minute, at least 2 inches (5 cm), and no more than 2.4 inches (6 cm), letting the chest recoil completely between every one.
Key points
- Incomplete recoil is the most common quality failure. The chest refilling is what generates the next perfusion, so come all the way up without lifting your hands off.
- Keep interruptions under 10 seconds, including the pause to swap rescuers or place pads. Every pause drops coronary pressure that takes several compressions to rebuild.
Give 2 rescue breaths
Open the airway with a head-tilt chin-lift, seal, and give 2 breaths of about 1 second each, then return to compressions for a ratio of 30 compressions to 2 breaths.
Key points
- Watch for the chest to just begin to rise. Over-inflating forces air into the stomach and pushes gastric contents back up into the airway.
- If the first breath does not go in, reposition the head and try once more, then get straight back on the chest rather than trying a third time.
Use the AED the moment it arrives
Power it on, follow the voice prompts, place the pads on bare dry skin, clear the patient for the analysis and any shock, then resume compressions immediately.
Key points
- Compressions continue while the pads are being placed. The only hands-off moments are the analysis and the shock itself.
- Resume compressions straight after the shock without stopping to recheck a pulse; the AED will tell you when to reassess.
- Swap the compressor every 2 minutes, at the AED's rhythm check, and continue until EMS takes over or the patient starts moving.
By patient age
Everything above is the adult standard. These are the parts that change.
Adult and adolescent
- Hands:
- Two hands, heel on the lower half of the breastbone
- Depth:
- At least 2 inches (5 cm), no more than 2.4 inches (6 cm)
- Ratio:
- 30:2 with one or two rescuers
Child, 1 year to puberty
- Hands:
- One or two hands, whichever reaches the depth
- Depth:
- About 2 inches (5 cm), roughly one third of chest depth
- Ratio:
- 30:2 with one rescuer, 15:2 with two
Infant, under 1 year
- Hands:
- Two fingers, or two thumbs encircling the chest with two rescuers
- Depth:
- About 1.5 inches (4 cm), roughly one third of chest depth
- Ratio:
- 30:2 with one rescuer, 15:2 with two
Authoritative resources
Every link below is an external site and opens in a new tab.
- American Heart Association: Hands-Only CPR(external link, opens in a new tab)
The two-step compression-only method, with the instructional video. This is what you teach a bystander in 60 seconds.
- American Heart Association: What is CPR(external link, opens in a new tab)
Plain-language overview of the chain of survival and where CPR sits in it.
- American Heart Association: CPR and ECC Guidelines(external link, opens in a new tab)
The source the numbers on this page come from. Check it directly whenever a new guidelines cycle publishes.
- American Red Cross: CPR steps(external link, opens in a new tab)
Step-by-step walkthrough with illustrations for adult, child and infant patients.
- American Red Cross: Find a CPR class(external link, opens in a new tab)
Certification search by location. Most fire departments require a current card at hire, so book this early.
Train for it, not just read about it
Apparatus Ready keeps your gear checklist, logs your workouts and practice runs, tracks a daily streak, and gives you a full length adaptive practice exam for the NREMT cognitive test. Free to start.