Hands-only CPR is recommended for any bystander who witnesses an adult suddenly collapse from a suspected cardiac arrest. You do not need training or certification. If you see someone go down and they’re unresponsive, you are the right person to start chest compressions immediately, because survival drops 7 to 10 percent for every minute without CPR.
The American Heart Association puts hands-only CPR on equal footing with conventional CPR (compressions plus rescue breaths) when a bystander is helping an adult who has suddenly collapsed outside a hospital. The distinction matters: specific groups of people and specific situations call for one approach over the other.
Bystanders With No Training
If you have never taken a CPR class, or you took one years ago and can’t remember the steps, hands-only CPR is designed for you. It removes the two biggest barriers that stop people from helping: uncertainty about technique and reluctance to perform mouth-to-mouth breathing on a stranger. The entire method is two steps. Call 911, then push hard and fast in the center of the chest until paramedics arrive.
When you call 911, the dispatcher can walk you through it in real time. Emergency dispatch centers use standardized protocols to help callers recognize cardiac arrest, typically by asking two questions: “Is the person conscious?” and “Is the person breathing normally?” If the answers point to cardiac arrest, the dispatcher will guide you through compression-only CPR over the phone. You don’t have to figure anything out on your own.
Trained Bystanders and When to Add Breaths
If you do have current CPR training, you can perform conventional CPR with both compressions and rescue breaths. For adults in sudden cardiac arrest, either approach works. But there are situations where the combination of compressions and breaths is clearly better:
- Infants and children. Pediatric cardiac arrest is more often caused by breathing problems than by a heart rhythm issue. A meta-analysis of pediatric cases found that conventional CPR produced a one-month survival rate of 18 percent compared to 12.3 percent for hands-only CPR. Neurological outcomes were also better: 9 percent with conventional CPR versus 6.3 percent with compressions alone.
- Drowning victims. The heart stopped because the person couldn’t breathe. Oxygen in the blood is already depleted, so rescue breaths are essential to restore it.
- Drug overdoses. Opioids and other substances suppress breathing first, leading to cardiac arrest second. The underlying problem is respiratory, so breaths matter.
- Unwitnessed collapse. If you didn’t see the person go down and don’t know how long they’ve been unresponsive, the oxygen remaining in their blood may already be used up. Rescue breaths help replenish it.
Medical professionals should always perform conventional CPR with compressions and breaths in the course of their duties. The hands-only recommendation is specifically for lay bystanders responding to a witnessed adult collapse.
Why Continuous Compressions Work for Adults
When an adult’s heart suddenly stops due to a cardiac rhythm problem, there is still oxygen in the blood for several minutes. The immediate need isn’t air. It’s circulation. Chest compressions act as a manual pump, pushing that oxygenated blood toward the brain and heart.
Every time you pause compressions, blood pressure in the coronary arteries drops and takes time to rebuild. Research published in Circulation found that the average pause to deliver two rescue breaths lasted 16 seconds, and during a typical resuscitation attempt, the heart received no circulatory support for nearly 60 percent of the time. That kind of interruption can compromise neurological recovery. Continuous compressions eliminate these gaps, keeping blood moving without pause until professional help arrives.
Correct Compression Technique
Place the heel of one hand in the center of the person’s chest, between the nipples. Stack your other hand on top and lock your fingers together. Keep your arms straight and use your body weight to push straight down. The target depth is at least 2 inches (5 centimeters) but no more than about 2.4 inches (6 centimeters). Studies of over 13,700 patients found that survival to hospital discharge improved with compressions in this range, while both shallower and deeper compressions were associated with worse outcomes.
Push at a rate of 100 to 120 compressions per minute. That’s roughly two per second. To keep the rhythm, think of a song you know at that tempo. “Stayin’ Alive” by the Bee Gees is the classic example, but “Uptown Funk,” “Eye of the Tiger,” “Rolling in the Deep,” and “I Wanna Dance with Somebody” all fall in the same range. The AHA maintains a full playlist of songs between 100 and 120 beats per minute for exactly this purpose.
Let the chest fully recoil between each compression. Leaning on the chest between pushes prevents the heart from refilling with blood, which defeats the purpose. If you get tired, and you will, switch off with another bystander every two minutes if possible. Fatigue causes compression quality to drop quickly.
Legal Protections for Bystanders
All 50 U.S. states and Washington, D.C. have Good Samaritan laws that protect people who provide emergency care from civil liability. If you crack a rib while performing CPR, which is common and sometimes unavoidable, these laws provide a legal defense against a lawsuit. The protections generally cover ordinary mistakes a reasonable person might make while trying to help. They do not cover gross negligence or intentional harm, but performing chest compressions on someone in cardiac arrest falls squarely within the kind of good-faith emergency response these laws were written to protect.
The details vary by state. Some states, like California, Connecticut, and Indiana, explicitly limit their protections to civil liability and don’t address criminal liability. In practice, criminal prosecution for attempting CPR on someone in cardiac arrest is essentially unheard of. The legal framework exists to encourage exactly the kind of action hands-only CPR requires: a bystander stepping in immediately rather than hesitating out of fear.