A child or infant in cardiac arrest is unresponsive, is not breathing normally, and has no reliable pulse; gasping or occasional irregular breaths do not count as normal breathing and still require immediate CPR. Call emergency services and start chest compressions at once. Do not wait for a pulse check you cannot perform confidently, and do not delay to look for other signs.
The physiology behind each sign
Cardiac arrest means the heart has stopped pumping blood effectively. Within seconds, blood flow to the brain falls to zero, and consciousness disappears. That is why unresponsiveness is an early, reliable sign: the brain cannot sustain awareness without oxygenated blood. A child who responds to voice or touch is not in cardiac arrest.
Breathing breaks down in a specific way. When circulation stops, the brainstem may still fire occasional gasps, called agonal respirations. These are slow, irregular, noisy, or snoring-like breaths that move little or no air. Laypeople often mistake gasping for breathing, which delays CPR. The rule is that normal breathing looks effortless and regular; anything else in an unresponsive child is treated as arrest until proven otherwise.
The pulse is the hardest sign for a non-clinician. In infants and children, a pulse can be difficult to locate, especially under stress, and a weak pulse may feel absent. Professional guidance therefore tells lay rescuers not to rely on pulse checks. The presence of normal breathing, responsiveness, and movement are more dependable indicators of circulation than a fingertip pulse search. A heart that is beating but not perfusing the body can also produce a faint pulse with no effective output, so pulse alone is an imperfect test even in trained hands.
A practical implication follows. The signs that matter most to a parent or bystander are the ones visible in under ten seconds: no response, no normal breathing. Everything else is secondary.
How fast arrest unfolds, with numbers
Cardiac arrest in children is usually the end stage of another problem. Respiratory failure and shock are the most common pathways, which is why pediatric arrest is often called asphyxial. This contrasts with adults, where sudden primary heart rhythm problems are more common. The distinction matters because oxygen-deprived arrest responds best to CPR that includes rescue breaths.
Survival falls quickly with time. Effective CPR and defibrillation within the first few minutes produce the best outcomes; every minute without compressions lowers the chance of survival. High-quality bystander CPR roughly doubles or triples survival compared with no bystander CPR in pediatric out-of-hospital arrest. Outcomes also depend on the cause, the child's age, and how quickly emergency care arrives.
The scale of the problem is smaller than in adults but not trivial. Out-of-hospital cardiac arrest in infants and children occurs at a fraction of the adult rate, but it carries a heavy toll because so many events are unwitnessed. Bystander CPR rates for children remain lower than for adults in many communities. The practical takeaway: the few minutes after collapse decide the outcome, and a bystander's actions carry most of the weight.
Edge cases that complicate the picture
Several situations mimic arrest or blur the signs, and each changes the response.
Seizure followed by unresponsiveness: a child who seizes and then does not wake or breathe normally needs CPR assessment, because post-seizure apnea can progress to arrest. Choking with sudden collapse: if a child was choking and then went limp, suspect complete airway obstruction and begin CPR with breaths emphasized. Drowning: the arrest is hypoxic from the start; rescue breaths are especially important, and CPR should begin as soon as the child is out of the water. Fright or breath-holding spells: these can cause brief fainting and even a short pause in breathing, but the child typically recovers on their own within a minute; a child who does not recover needs CPR. Opioid exposure: pinpoint pupils with slow or absent breathing in an unresponsive child suggest opioid poisoning, which requires naloxone plus CPR if not breathing normally.
The counterintuitive professional caveat: a child can have a palpable pulse and still be in cardiac arrest. Cardiac arrest is defined by the absence of effective circulation, not by the absence of every heartbeat. Pulseless electrical activity and profound shock can produce a weak, difficult-to-find pulse while the body is not being perfused. This is exactly why guidelines direct bystanders toward responsiveness and breathing, not pulse.
Misconceptions to discard
One common error is waiting for a pulse. Lay rescuers should not spend time hunting for a pulse; if the child is unresponsive and not breathing normally, start CPR. Another is assuming gasping means the child is breathing. Agonal gasps are a sign of arrest, not recovery.
A third error is fearing harm from compressions. In an unresponsive child who is not breathing normally, the risk of doing nothing is far greater than the risk of CPR. A brief, reversible injury from compressions is acceptable compared with certain death from untreated arrest.
A fourth misconception is that CPR always requires mouth-to-mouth. Compression-only CPR is better than no CPR for adults with sudden collapse, but for children the arrest is usually hypoxic, so rescue breaths matter. If a rescuer is unwilling or unable to give breaths, compression-only CPR is still far better than nothing.
A fifth error is delaying the emergency call. Call first or have someone call while you start compressions; do not wait until after CPR to summon help.
What to do, in order
The following sequence applies to any unresponsive child or infant. Follow current local emergency protocols.
Check response: tap the child and shout. If there is no response, shout for help and have someone call emergency services; if alone with a phone, call on speaker. Check breathing for no more than 10 seconds: look for chest movement, listen, and feel for air. Occasional gasps are not normal breathing. Start compressions immediately if not breathing normally. For infants, use two fingers on the breastbone just below the nipple line; for children, use one or two hands on the lower half of the breastbone. Push hard and fast, at least one-third the depth of the chest, at 100 to 120 compressions per minute. Give rescue breaths if trained: 2 breaths after every 30 compressions for a lone rescuer; switch to 15:2 with two rescuers for infants and children. If untrained, continue compressions. Use an AED as soon as one is available: apply pediatric pads if present, otherwise adult pads, and follow the voice prompts. Do not delay compressions to fetch a device alone. Continue until the child breathes normally, moves purposefully, or emergency responders take over. Handoff to professionals without pausing compressions longer than necessary.
Limits of these signs
No sign is perfectly sensitive. Some children in arrest retain brief gasping that looks like breathing, and some have a pulse that is present but ineffective. Conversely, a child in severe shock or a post-seizure state may look arrest-like but recover with positioning and time. These overlaps are why guidelines simplify the message for bystanders: unresponsive plus not breathing normally equals start CPR.
The signs described here are for emergency recognition, not diagnosis. They cannot tell you the cause of arrest or whether CPR will succeed. They only tell you when to act.
Several thresholds appear across sources and should be reconciled plainly. Breathing assessment is capped at about 10 seconds. Compression rate is 100 to 120 per minute. Compression depth is at least one-third of chest depth, roughly 1.5 inches for infants and 2 inches for children. The compression-to-breath ratio is 30:2 for a single rescuer and 15:2 for two rescuers with infants and children. These numbers are consistent across major resuscitation guidelines; where sources differ slightly, follow the protocol taught in your local training.
This article is general educational information about emergency recognition, not a diagnosis, treatment plan, or substitute for CPR training. It does not promise any outcome from CPR. For hands-on skills, take a course from a qualified local provider such as the American Red Cross or American Heart Association, and in any immediate emergency call your local emergency number.