I was involved in a resuscitation attempt where the upper 70's year old man arrested in front of one of his children. CPR was started with instructions from dispatch. We worked the arrest for 50 minutes or so, the patient remained in fine v-fib the entire time. He was shocked 6 times, given 7 mg of epi. 1/10000, 450 mg amiodarone, 100 meq. if sodium bicarb, and 2 mg of Narcan, At what point would you have stopped effort to resuscitate (contact med control)?