Final answer:
The most important drug to administer to a child in cardiac arrest while CPR is being performed is Epinephrine.
Step-by-step explanation:
The most important drug to administer to a child in cardiac arrest while CPR is being performed is Epinephrine. Epinephrine, also known as adrenaline, is a medication that stimulates the heart and helps restore normal heart rhythm. It can be given through an injection or an auto-injector device.
In addition to Epinephrine, other medications that may be used during cardiac arrest include Amiodarone and Lidocaine to help stabilize the heart's electrical activity, and Sodium Bicarbonate to correct acid-base imbalances in the body.
It is important to note that the administration of these medications should be done by trained healthcare professionals.