In an infant, cardiac arrest is characterized by unresponsiveness to touch or sound, absence of breathing, and no pulse.

The first step in infant CPR is to check for responsiveness by gently shaking and shouting to the infant.

During infant CPR, 30 chest compressions should be given at a rate of 100 to 120 compressions per minute.

Chest compressions should be given to an infant at a depth of approximately 1/3 the depth of the chest.

During infant CPR, two rescue breaths should be given after every 30 chest compressions.

During infant CPR, both hands should be placed on the infant's sternum, with the thumbs side by side and the fingers interlaced.

CPR should be continued for an infant until the infant starts breathing, the infant's pulse returns, or emergency medical services arrive.

Common challenges faced during infant CPR include difficulty in maintaining an open airway, difficulty in giving chest compressions, and difficulty in giving rescue breaths.

The recommended ratio of chest compressions to rescue breaths during infant CPR is 30:2.

The recommended rate of chest compressions during infant CPR is 100 to 120 compressions per minute.

The recommended depth of chest compressions during infant CPR is 1/3 the depth of the chest.

The recommended duration of each chest compression during infant CPR is 0.5 seconds.

The recommended duration of each rescue breath during infant CPR is 1 second.

The recommended volume of each rescue breath during infant CPR is 100 mL.