The medical act of resuscitation is permitted by God.
Resurrection is a divine process that only God can do, but we can be resuscitated after we are clinically (and actually) dead. It happens thousands of times every day in hospitals all over the world.
Watch this video at about the 20 minute mark, or at least the first few minutes of this from a medical doctor (Dr. Rawlins) who also became a Christian. He explains the distinction between resurrection and resuscitation (at 21:00).
I have read hundreds of these accounts. I also read a book about shared death experiences where the patient dies and those with them actually see supernatural things. We are spirit, body and soul. When our body dies we leave for a different dimension.
Please pray for this girl, Cassandra. She is very special.