2 CPR Fundamentals

Recognize the emergency and act

Begin CPR when a person is unresponsive and not breathing normally. Gasping is not normal breathing. Call 911 or the local emergency number, get an AED, and start CPR promptly. Follow the emergency dispatcher’s instructions.

If you are not trained to check a pulse, do not delay CPR to try to find one. Use a firm, flat surface when feasible, but do not postpone CPR to move the person unnecessarily. Hands-on certified training helps build confidence and skill.

Age groups and CPR priorities

The age categories guide which compression techniques and depths to use:

• Adult: A person with signs of puberty or older.

• Child: Approximately one year old until puberty.

• Infant: Younger than approximately one year, excluding a newborn at birth. Newborn resuscitation follows separate guidance.

For adults, children, and infants, aim for a compression rate of $100\text{–}120$ per minute. Use the depth appropriate for the person’s age, allow full chest recoil, keep pauses as short as possible, and avoid excessive breaths.

Compression depth and technique

Use the person’s age to choose compression depth and hand position. For each age group, compress the breastbone and aim for a steady rate of $100\text{–}120$ compressions per minute.

• Adult: Compress at least $2$ inches ($5\text{ cm}$), but no more than $2.4$ inches ($6\text{ cm}$). Place the heel of one hand in the center of the chest on the lower half of the breastbone and put the other hand on top. Keep your shoulders over your hands and elbows straight.

• Child: Compress about one-third of the chest’s front-to-back depth, approximately $2$ inches ($5\text{ cm}$). Use one or two hands on the lower half of the breastbone, choosing the position that allows effective compressions for the child’s size.

• Infant: Compress about one-third of the chest’s front-to-back depth, approximately $1.5$ inches ($4\text{ cm}$). Use the heel of one hand or the two-thumb, encircling-hands technique. If you cannot encircle the chest, use one hand.

The two-finger method is no longer recommended for infant compressions because it may not achieve adequate depth.

Breaths and compression patterns

After each set of compressions, give $2$ breaths when able. Open the airway with a head-tilt–chin-lift unless a neck injury is suspected. Each breath should last only long enough to make the chest visibly rise; then resume compressions promptly. For an infant, make a gentle seal over the mouth and nose. Avoid forceful or repeated breaths that delay compressions.

The compression-to-breath pattern depends on age and the number of rescuers:

• Adult: $30$ compressions followed by $2$ breaths.

• Child: One rescuer uses $30:2$; two rescuers use $15:2$.

• Infant: One rescuer uses $30:2$; two rescuers use $15:2$.

For an adult who suddenly collapses, a lay rescuer who is untrained or unwilling to give breaths should provide hands-only CPR—continuous chest compressions—and follow dispatcher instructions. For infants and children, CPR with compressions and breaths is especially important because cardiac arrest often follows a breathing problem. If you cannot or will not give breaths, compression-only CPR is better than doing nothing.

Coordinate rescuers and use an AED

When several rescuers are present, perform tasks in parallel rather than waiting for one task to finish:

1. One rescuer checks responsiveness and breathing, calls for help, and starts compressions.

2. Another calls 911 and brings an AED.

3. If trained rescuers are available, one can manage breaths while another compresses; a third can prepare the AED and coordinate the response.

4. Change the compressor about every $2$ minutes, or sooner if the compressor is tired. Plan the handoff so the pause is brief.

5. When the AED arrives, turn it on, attach the pads as shown, and follow its voice prompts. Make sure everyone is clear while it analyzes or delivers a shock. Resume CPR immediately when instructed, whether or not a shock is advised.

For an infant or child, use pediatric pads or an attenuator if available. If they are not available, use the AED at hand rather than delaying defibrillation.

Avoid common practice errors

Avoid errors that reduce the quality or delay the start of CPR:

• Waiting too long: Gasping can be mistaken for normal breathing. Treat unresponsiveness with absent or abnormal breathing as an emergency.

• Compressing too slowly or too shallowly: Keep a brisk, steady pace and meet the depth appropriate for the person’s age.

• Leaning on the chest: Let the chest return fully after every compression.

• Pausing too often or too long: Keep interruptions brief, including for breaths, AED analysis, and rescuer changes. For children and infants, pauses should be under $10$ seconds whenever possible.

• Giving large, fast, or frequent breaths: Give only enough air to make the chest rise, then return to compressions.

• Using the wrong infant technique: Do not use two-finger chest compressions; use the heel of one hand or the two-thumb, encircling-hands technique.

• Delaying for a perfect setup: Start CPR and use an available AED as soon as possible. Uncertainty about equipment or roles should not prevent action.

• automated external defibrillator (AED)