1. * Staff Anesthesiologist, † Medical Student, | Professor, Department of Anesthesiology and Critical Care Medicine, ‡ Statistician, Public Health Unit, School of Medicine, Avicenne Hospital, Paris 13 University–Assistance Publique-Hôpitaux de Paris, Bobigny, France. § Assistant Professor, Department of Anesthesiology, Perioperative and Pain Medicine, Brigham and Women's Hospital, Harvard Medical S