1. Safar Center for Resuscitation Research, and Department of Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
2. Department of Neurosurgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
3. Department of Epidemiology and Public Health, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
4. Safar Center for Resuscitation Research, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
5. Safar Center for Resuscitation Research, and Department of Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania