Final answer:
In case of a child's or an infant's sudden collapse, check for responsiveness, call for emergency help, and if trained, provide CPR or take action to clear a choking obstruction. Stay calm and continue care until professional help arrives or the child recovers.
Step-by-step explanation:
If you witness the sudden collapse of an infant or child, the first step is to determine whether the child is conscious or not. Check for responsiveness by gently tapping the child and calling their name. If there is no response, call for emergency medical help immediately. After calling for help, if the child is not breathing, begin CPR if you are trained to do so. For an infant, you would use two fingers for chest compressions; for a child, you would use one or two hands (depending on the size of the child) for compressions.
If the collapse is due to a choking incident, and the child is still conscious, give five back blows and five chest thrusts for an infant, or back blows and abdominal thrusts (like the Heimlich maneuver) for a child. If these actions do not clear the airway obstruction, continue CPR until help arrives or the child begins breathing on their own.
In any emergency situation involving children or infants, it's crucial to act quickly and effectively while keeping as calm as possible to provide the best chance of a positive outcome. Remember that helping those in need is a universal responsibility, and immediate action could save a life.