https://newsroom.heart.org/news/updated-cpr-guidelines-released-for-pediatric-and-neonatal-emergency-care-and-resuscitation

For a small child, one-hand compressions can be used. However, for infants with a single rescuer, the technique is to using two fingers (index and middle finger) placed in the center of the chest, just below the nipple line, to deliver 30 compressions followed by 2 breaths. In case the rescuer is unable to compress to the recommended depth, one-hand compressions may be used.

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