F. We and . Mercier, Port Mort, France) for data management and Micheal Egan for his help in the revision of the manuscript, This research was supported by Wyeth Pharmaceuticals France

J. Garnacho-montero, J. Garcia-garmendia, A. Barrero-almodovar, F. Jimenez-jimenez, C. Perez-paredes et al., Impact of adequate empirical antibiotic therapy on the outcome of patients admitted to the intensive care unit with sepsis*, Critical Care Medicine, vol.31, issue.12, pp.2742-2751, 2003.
DOI : 10.1097/01.CCM.0000098031.24329.10

M. Kollef, G. Sherman, S. Ward, and V. Fraser, Inadequate Antimicrobial Treatment of Infections, Chest, vol.115, issue.2, pp.462-474, 1999.
DOI : 10.1378/chest.115.2.462

P. Montravers, R. Gauzit, C. Muller, J. Marmuse, A. Fichelle et al., Emergence of Antibiotic-Resistant Bacteria in Cases of Peritonitis After Intraabdominal Surgery Affects the Efficacy of Empirical Antimicrobial Therapy, Clinical Infectious Diseases, vol.23, issue.3, pp.486-494, 1996.
DOI : 10.1093/clinids/23.3.486

M. Leone, A. Bourgoin, S. Cambon, M. Dubuc, J. Albanese et al., Empirical antimicrobial therapy of septic shock patients: Adequacy and impact on the outcome*, Critical Care Medicine, vol.31, issue.2, pp.462-467, 2003.
DOI : 10.1097/01.CCM.0000050298.59549.4A

A. Kumar, D. Roberts, K. Wood, B. Light, J. Parrillo et al., Duration of hypotension before initiation of effective antimicrobial therapy is the critical determinant of survival in human septic shock*, Critical Care Medicine, vol.34, issue.6, pp.1589-1596, 2006.
DOI : 10.1097/01.CCM.0000217961.75225.E9

R. Dellinger, M. Levy, J. Carlet, J. Bion, M. Parker et al., Surviving Sepsis Campaign, Critical Care Medicine, vol.41, issue.2, pp.296-327, 2008.
DOI : 10.1097/CCM.0b013e31827e83af

R. Ferrer, A. Artigas, M. Levy, J. Blanco, G. Gonzalez-diaz et al., Improvement in Process of Care and Outcome After a Multicenter Severe Sepsis Educational Program in Spain, JAMA, vol.299, issue.19, pp.2294-2303, 2008.
DOI : 10.1001/jama.299.19.2294

F. Gao, T. Melody, D. Daniels, S. Giles, and S. Fox, The impact of compliance with 6-hour and 24-hour sepsis bundles on hospital mortality in patients with severe sepsis: a prospective observational study, Critical Care, vol.9, issue.6, pp.764-770, 2005.
DOI : 10.1186/cc3909

S. Micek, N. Roubinian, T. Heuring, M. Bode, J. Williams et al., Before???after study of a standardized hospital order set for the management of septic shock*, Critical Care Medicine, vol.34, issue.11, pp.2707-2713, 2006.
DOI : 10.1097/01.CCM.0000241151.25426.D7

L. Lehmann, J. Alvarez, K. Hunfeld, A. Goglio, G. Kost et al., Potential clinical utility of polymerase chain reaction in microbiological testing for sepsis, Critical Care Medicine, vol.37, issue.12, pp.3085-3090, 2009.
DOI : 10.1097/CCM.0b013e3181b033d7

M. Kollef and V. Fraser, Antibiotic Resistance in the Intensive Care Unit, Annals of Internal Medicine, vol.134, issue.4, pp.298-314, 2001.
DOI : 10.7326/0003-4819-134-4-200102200-00014

D. Paterson and L. Rice, Empirical Antibiotic Choice for the Seriously Ill Patient: Are Minimization of Selection of Resistant Organisms and Maximization of Individual Outcome Mutually Exclusive?, Clinical Infectious Diseases, vol.36, issue.8, pp.1006-1012, 2003.
DOI : 10.1086/374243

M. Warren, A. Gibb, and T. Walsh, Antibiotic prescription practice in an intensive care unit using twice-weekly collection of screening specimens: a prospective audit in a large UK teaching hospital, Journal of Hospital Infection, vol.59, issue.2, pp.90-95, 2005.
DOI : 10.1016/j.jhin.2004.09.014

D. Bergmans, M. Bonten, C. Gaillard, F. Van-tiel, S. Van-der-geest et al., Indications for antibiotic use in ICU patients: a one-year prospective surveillance, Journal of Antimicrobial Chemotherapy, vol.39, issue.4, pp.527-535, 1997.
DOI : 10.1093/jac/39.4.527

M. Erlandsson, L. Burman, O. Cars, H. Gill, L. Nilsson et al., Prescription of antibiotic agents in Swedish intensive care units is empiric and precise, Scandinavian Journal of Infectious Diseases, vol.52, issue.4, pp.63-69, 2007.
DOI : 10.1378/chest.111.3.676

C. Luyt, A. Combes, P. Aegerter, B. Guidet, J. Trouillet et al., Mortality among patients admitted to intensive care units during weekday day shifts compared with ???off??? hours*, Critical Care Medicine, vol.35, issue.1, pp.3-11, 2007.
DOI : 10.1097/01.CCM.0000249832.36518.11

L. Gall, J. Lemeshow, S. Saulnier, and F. , A New Simplified Acute Physiology Score (SAPS II) Based on a European/North American Multicenter Study, JAMA: The Journal of the American Medical Association, vol.270, issue.24, pp.2957-2963, 1993.
DOI : 10.1001/jama.1993.03510240069035

W. Mccabe and G. Jackson, Gram-Negative Bacteremia, Archives of Internal Medicine, vol.110, issue.6, pp.847-855, 1962.
DOI : 10.1001/archinte.1962.03620240029006

O. Grady, N. Barie, P. Bartlett, J. Bleck, T. Garvey et al., Practice Guidelines for Evaluating New Fever in Critically Ill Adult Patients, Clinical Infectious Diseases, vol.26, issue.5, pp.1042-1059, 1998.
DOI : 10.1086/520308

J. Vincent, R. Moreno, J. Takala, S. Willatts, D. Mendonca et al., The SOFA (Sepsis-related Organ Failure Assessment) score to describe organ dysfunction/failure, Intensive Care Medicine, vol.21, issue.7, pp.707-710, 1996.
DOI : 10.1007/BF01709751

. Société-francaise-d, Anesthésie-Réanimation SFAR ed: Antibiothérapie probabiliste des états septiques graves. Conférence d'experts Paris, 2004.

F. Harrell, K. Lee, and D. Mark, MULTIVARIABLE PROGNOSTIC MODELS: ISSUES IN DEVELOPING MODELS, EVALUATING ASSUMPTIONS AND ADEQUACY, AND MEASURING AND REDUCING ERRORS, Statistics in Medicine, vol.15, issue.4, pp.361-387, 1996.
DOI : 10.1002/(SICI)1097-0258(19960229)15:4<361::AID-SIM168>3.0.CO;2-4

B. Hartmann, A. Junger, D. Brammen, R. Röhrig, J. Klasen et al., Review of antibiotic drug use in a surgical ICU: Management with a patient data management system for additional outcome analysis in patients staying more than 24 hours, Clinical Therapeutics, vol.26, issue.6, pp.915-914, 2004.
DOI : 10.1016/S0149-2918(04)90135-X

A. Erbay, H. Bodur, E. Akinci, and A. Colpan, Evaluation of antibiotic use in intensive care units of a tertiary care hospital in Turkey, Journal of Hospital Infection, vol.59, issue.1, pp.53-61, 2005.
DOI : 10.1016/j.jhin.2004.07.026

J. Vincent, J. Rello, J. Marshall, E. Silva, A. Anzueto et al., International Study of the Prevalence and Outcomes of Infection in Intensive Care Units, JAMA, vol.302, issue.21, pp.2323-2329, 2009.
DOI : 10.1001/jama.2009.1754

J. Lefrant, L. Muller, A. Raillard, B. Jung, L. Beaudroit et al., Oc study Group in the AzuRéa Group: Reduction of the severe sepsis or septic shock associated mortality by reinforcement of the recommendations bundle: A multicenter study

P. Montravers, B. Veber, C. Auboyer, H. Dupont, R. Gauzit et al., Diagnostic and therapeutic management of nosocomial pneumonia in surgical patients: Results of the Eole study, Critical Care Medicine, vol.30, issue.2, pp.368-375, 2002.
DOI : 10.1097/00003246-200202000-00017

I. Gyssens, Quality measures of antimicrobial drug use, International Journal of Antimicrobial Agents, vol.17, issue.1, pp.9-19, 2001.
DOI : 10.1016/S0924-8579(00)00208-9

J. Fagon, J. Chastre, A. Hance, Y. Domart, J. Trouillet et al., Evaluation of Clinical Judgment in the Identification and Treatment of Nosocomial Pneumonia in Ventilated Patients, Chest, vol.103, issue.2, pp.547-553, 1993.
DOI : 10.1378/chest.103.2.547

T. Helling, C. Van-way, S. Krantz, K. Bertram, and A. Stewart, The value of clinical judgment in the diagnosis of nosocomial pneumonia, The American Journal of Surgery, vol.171, issue.6, pp.570-575, 1996.
DOI : 10.1016/S0002-9610(96)00040-2

J. Rello, D. Ollendorf, G. Oster, M. Vera-llonch, L. Bellm et al., Epidemiology and Outcomes of Ventilator-Associated Pneumonia in a Large US Database, Chest, vol.122, issue.6, pp.2115-2121, 2002.
DOI : 10.1378/chest.122.6.2115

N. Singh, M. Falestiny, P. Rogers, M. Reed, J. Pularski et al., Pulmonary Infiltrates in the Surgical ICU, Chest, vol.114, issue.4, pp.1129-1136, 1998.
DOI : 10.1378/chest.114.4.1129

J. Rello, L. Vidaur, A. Sandiumenge, A. Rodriguez, B. Gualis et al., De-escalation therapy in ventilator-associated pneumonia*, Critical Care Medicine, vol.32, issue.11, pp.2183-2190, 2004.
DOI : 10.1097/01.CCM.0000145997.10438.28

P. Houck, D. Bratzler, W. Nsa, A. Ma, and J. Bartlett, Timing of Antibiotic Administration and Outcomes for Medicare Patients Hospitalized With Community-Acquired Pneumonia, Archives of Internal Medicine, vol.164, issue.6, pp.637-644, 2004.
DOI : 10.1001/archinte.164.6.637

C. Lu, C. Huang, W. Chang, C. Chang, B. Cheng et al., Community-acquired bacterial meningitis in adults: the epidemiology, timing of appropriate antimicrobial therapy, and prognostic factors, Clinical Neurology and Neurosurgery, vol.104, issue.4, pp.352-358, 2002.
DOI : 10.1016/S0303-8467(02)00052-5

C. Frei, M. Restrepo, E. Mortensen, and D. Burgess, Impact of Guideline-Concordant Empiric Antibiotic Therapy in Community-Acquired Pneumonia, The American Journal of Medicine, vol.119, issue.10, pp.865-871, 2006.
DOI : 10.1016/j.amjmed.2006.02.014

E. Ibrahim, S. Ward, G. Sherman, R. Schaiff, V. Fraser et al., Experience with a clinical guideline for the treatment of ventilator-associated pneumonia, Critical Care Medicine, vol.29, issue.6, pp.1109-1115, 2001.
DOI : 10.1097/00003246-200106000-00003

M. Levy, R. Dellinger, S. Towsend, W. Linde-zwirble, J. Marshall et al., Surviving Sepsis Campaign, Critical Care Medicine, vol.43, issue.1, pp.367-374, 2010.
DOI : 10.1097/CCM.0000000000000723

P. George and A. Morris, Pro/con debate: Should antimicrobial stewardship programs be adopted universally in the intensive care unit?, Critical Care, vol.14, issue.1, p.205, 2010.
DOI : 10.1186/cc8219