 Because of the difficult position of the aneurysm, Reynolds was predicted to have no chance of surviving surgery for its removal.As a last resort, Robert F. Spetzler — a neurosurgeon of the Barrow Neurological Institute in Phoenix, Arizona — decided that a rarely performed procedure, known as hypothermic cardiac arrest, could improve Reynolds's chances of surviving surgical removal of the aneurysm.During this procedure, also known as a standstill operation, Reynolds's body temperature was lowered to 50 °F (10 °C), her breathing and heartbeat stopped, and the blood drained from her head.