When giving CPR to an infant, you can use two compression techniques: the two-finger technique (index and middle fingers of one hand, for solo rescuers) and the two-thumb encircling-hands technique (both thumbs side by side with hands wrapped around the torso, for two or more rescuers). Both target a rate of 100 to 120 compressions per minute, a depth of about one-third the anteroposterior chest diameter (roughly 1.5 inches, or 4 cm), and full recoil between compressions.
The two techniques and the physics behind them
Infant chest compressions work by raising intrathoracic pressure and directly squeezing the heart between the sternum and spine. The goal is to generate enough forward flow to keep the brain and coronary arteries perfused until definitive care arrives. The technique you choose changes how efficiently that force is transmitted.
The two-finger technique uses the index and middle fingertips of one hand, placed on the lower half of the sternum just below the nipple line. Because the contact area is small, the force is concentrated, but the fingers fatigue quickly and tend to bounce rather than recoil cleanly. It exists mainly because it lets a single rescuer compress and ventilate without repositioning.
The two-thumb encircling-hands technique wraps both hands around the infant's torso so the thumbs rest side by side on the sternum. This does two things mechanically. First, it doubles the contact area, spreading force across the sternum instead of punching one spot. Second, the encircling hands splint the rib cage, which reduces paradoxical chest-wall motion and improves the fraction of each push that becomes forward blood flow. It is the preferred technique whenever two or more rescuers are present.
A counterintuitive detail: harder is not better past a point. In infants, excessive depth or a "stabbing" fingertip compresses the heart against the spine inefficiently and raises injury risk to the liver and lungs. The target is a smooth, calibrated squeeze to about one-third of chest depth, not maximal force.
Quantified context: rate, depth, and the 30:2 ratio
The numbers that define infant CPR are tight and non-negotiable. Compressions run at 100 to 120 per minute, the same tempo as the Bee Gees' "Stayin' Alive." Depth is about 4 cm, or roughly 1.5 inches, which corresponds to one-third of the anteroposterior diameter of an infant's chest. Full recoil is required after every compression so the heart refills.
For a single rescuer, the compression-to-ventilation ratio is 30:2. For two rescuers, it shifts to 15:2 for infants and children, because a second pair of hands can deliver breaths faster and the higher compression fraction matters more. Each ventilation is a gentle puff, just enough to make the chest rise, delivered over about 1 second.
These thresholds come from the American Heart Association's pediatric basic life support guidance . The shift from 30:2 to 15:2 for two rescuers reflects a simple tradeoff: more compressions per minute means more perfusion, but you still need oxygen delivered.
| Technique | Rescuers | Contact points | Typical fatigue | Preferred use |
|---|---|---|---|---|
| Two-finger | 1 | Index + middle fingertip | High, minutes | Solo rescuer |
| Two-thumb encircling | 2+ | Both thumbs, hands splint torso | Low | Team response |
| One-hand (older child) | 1–2 | Heel of one hand | Moderate | Child, not infant |
| Two-hand (older child) | 2 | Both hands stacked | Low | Child, not infant |
| Thumb-only (neonate) | 1–2 | One or two thumbs | Moderate | Delivery room |
The neonate row matters for a different reason: newborn resuscitation in the delivery room sometimes uses a thumb technique with a different ratio, and mixing protocols is a common source of error.
Edge cases that change the decision
Several situations force you to deviate from the default.
A lone rescuer with a small infant may find two-finger compressions easier to sustain while also giving breaths, even though two-thumb is mechanically superior. Switch to two-thumb the moment a second trained person arrives.
If the infant has a suspected spinal injury, you still compress, but minimize torso rotation. The encircling-hands technique actually helps here because it stabilizes the chest.
In a newborn immediately after birth, follow the neonatal resuscitation algorithm, which may call for a 3:1 compression-to-ventilation ratio with a different depth target . This is a delivery-room scenario, not standard infant CPR.
Obesity, chest-wall deformity, or a sternal fracture changes hand placement. Reassess landmarks and keep compressions on the lower sternum, never on the ribs or the xiphoid.
Common misconceptions and the professional caveat
Myth one: you must find a pulse before starting compressions. In practice, lay rescuers should begin compressions immediately on an unresponsive, non-breathing infant. Pulse checks are unreliable and delay flow.
Myth two: rescue breaths are optional. For infants, the cause of arrest is often respiratory, so ventilation is not optional. Compressions alone treat a circulatory problem that may not be the primary one.
Myth three: the two-finger technique is the "official" infant method. It is one acceptable method, not the only one. Guidelines explicitly permit and often prefer two-thumb when help is available.
Professional caveat: chest compression quality degrades within about 1 to 2 minutes even in trained rescuers. That is why guidelines emphasize switching compressors every 2 minutes during prolonged resuscitation. The technique you choose should account for who can sustain quality, not just who can start.
Practical actions and thresholds
Use this sequence when you find an unresponsive infant.
Confirm unresponsiveness and absent or abnormal breathing for no more than 10 seconds. Call for help or activate emergency services; if alone with no phone, give about 1 minute of CPR before leaving to call. Begin compressions at 100 to 120 per minute, depth about 1.5 inches (one-third chest diameter). Give 30 compressions to 2 breaths if alone; switch to 15:2 when a second rescuer arrives. Switch to the two-thumb encircling technique as soon as a partner is available. Rotate compressors every 2 minutes to preserve depth and rate.
Red-flag warnings:
Do not compress over the xiphoid process or the ribs; this risks liver laceration and poor flow. Do not lean on the chest between compressions; full recoil is required for refill. Do not give large breaths; overventilation raises intrathoracic pressure and reduces cardiac output. Do not delay compressions to search for a pulse or to reposition excessively. Do not stop compressions to check response unless the infant shows clear signs of life.
Timeline of an infant resuscitation
| Time from arrest | Action | Target |
|---|---|---|
| 0–10 seconds | Check responsiveness and breathing | No more than 10 seconds |
| 10–30 seconds | Call for help / activate EMS | Immediate |
| 30 seconds–2 min | Start compressions, 30:2 if alone | 100–120/min |
| 2 min | Switch compressor, reassess | Preserve depth |
| 2–10 min | Continue CPR, prepare AED | Minimal interruptions |
| 10+ min | Advanced life support arrival | Transition of care |
| Until ROSC or EMS | Sustained high-quality CPR | Compression fraction >80% |
The compression fraction target, the proportion of resuscitation time spent compressing, is a quality metric that teams track. Interruptions longer than 10 seconds drop coronary perfusion pressure and are discouraged.
Limitations and what this guide cannot tell you
This article explains stable mechanics and guideline-level targets. It cannot substitute for hands-on certification, and it cannot account for an individual infant's anatomy, underlying condition, or the cause of arrest. Depth and rate targets are population-level guidance, not a prescription for one patient.
Skill decay is real: without refresher training, compression quality falls within months. The technique names and numbers here are current to major resuscitation guidance, but protocols can be revised, so verify against the latest official course materials before relying on them in an emergency.
This article is general educational information, not a diagnosis, treatment plan, or substitute for trained CPR instruction. It does not promise any outcome. For an infant in distress, call local emergency services immediately and follow dispatcher instructions; enroll in an accredited CPR course to practice these techniques on a manikin with a qualified instructor.