A terrorist nuclear strike in a major U.S. city would kill and injure so many people that disaster planners rewrote the rules for dealing with casualties. Their analysis is part of a comprehensive effort to develop a medical response plan for dealing with a 10-kiloton nuclear bomb, which would pack roughly the explosive force of the Hiroshima blast or 5,000 Oklahoma City truck bombs. Demand for medical care would be almost inconceivable. In Washington D.C., a city with 38 ambulances, and neighboring communities, at least 930,000 people would seek medical care. More than 70,000 would need hospitalization, vastly overflowing the city 3,600 hospital beds. There would be at least 1,000 severely injured trauma patients for every available operating room, said the co-author, a radiation expert at the Dana Farber Cancer Institute. The reports were released March 14 in the Journal Disaster Medicine and Public Health Preparedness. Any medical centers left standing for miles around ground zero would be overwhelmed by dazed and bleeding survivors, who would quickly drain stockpiles of supplies that might take days to replenish, the analysis finds. The research indicates first responders who lack medical supplies can save more lives by focusing on victims with moderate injuries rather than on those whose injuries are severe, usually the top priority on the battlefield and in more common disasters. An ethical analysis concluded it would be appropriate to use scarce medications to provide pain relief and comfort to those who may not make it.