Starting on Jan. 1, New York City ambulances will take many cardiac arrest patients only to hospitals that use a delicate cooling therapy believed to reduce the chances of brain damage and increase the chances of survival, even if it means bypassing closer emergency rooms. The move by the city’s Fire Department and Emergency Medical Service, after a year of preparation, indicates a shift away from the prevailing view among emergency workers and the public that how fast critically ill patients reach the hospital is more important than which hospital treats them. It amounts to an endorsement by the Bloomberg...