1. Department of Anesthesiology and Intensive Care, Bégin Military Teaching Hospital, 69 avenue de Paris, 94160 Saint-Mandé, France
2. Intensive Care Unit, Bégin Military Teaching Hospital, 94160 Saint-Mandé, France
3. Intensive Care Unit, Percy Military Teaching Hospital, 92140 Clamart, France
4. Naval Branch Health Clinic, United States Navy, Lakehurst, NJ 08733-5006, USA