title: Mediastinitis due to Gram-negative bacteria is associated with increased mortality.
abstract: The aim of this study was to describe the features of a large cohort of patients with postoperative mediastinitis, with particular regard to Gram-negative bacteria (GNB), and assess their outcome. This bicentric retrospective cohort included all patients who were hospitalized in the Intensive Care Unit with mediastinitis after cardiac surgery during a 9-year period. Three hundred and nine patients developed a mediastinitis with a mean age of 65 years and a mean standard Euroscore of six points. Ninety-one patients (29.4%) developed a GNB mediastinitis (GNBm). Of the 364 pathogens involved, 103 GNB were identified. GNBm were more frequently polymicrobial (44% versus 3.2%; p <0.001). Being female was the sole independent risk factor of GNBm in multivariate analysis. Initial antimicrobial therapy was significantly more frequently inappropriate with GNBm compared with other microorganisms (24.6% versus 1.9%; p <0.001). Independent risk factors for inappropriateness of initial antimicrobial treatment were GNBm (OR = 8.58, 95%CI 2.53-29.02, p 0.0006), and polymicrobial mediastinitis (OR = 4.52, 95%CI 1.68-12.12, p 0.0028). GNBm were associated with more drainage failure, secondary infection, need for prolonged mechanical ventilation and/or use of vasopressors. Thirty-day hospital mortality was significantly higher with GNBm (31.9 % versus 17.0%; p 0.004). GNBm was identified as an independent risk factor of hospital mortality (OR = 2.31, 95%CI 1.16-4.61, p 0.0179).
authors: Department of intensive care, Assistance Publique-Hôpitaux de Paris, Hôpital Européen Georges Pompidou, Paris, France; Université Paris-Descartes, Faculté de Médecine, Paris, France.
authors: H
authors: H
authors: Charbonneau
authors: J M
authors: JM
authors: Maillet
authors: M
authors: M
authors: Faron
authors: O
authors: O
authors: Mangin
authors: E
authors: E
authors: Puymirat
authors: P
authors: P
authors: Le Besnerais
authors: L
authors: L
authors: Du Puy-Montbrun
authors: P
authors: P
authors: Achouh
authors: J L
authors: JL
authors: Diehl
authors: J-Y
authors: JY
authors: Fagon
authors: J-L
authors: JL
authors: Mainardi
authors: E
authors: E
authors: Guerot
mesh_terms: D000368:Aged; D006348:Cardiac Surgical Procedures / Q000009:adverse effects; D002423:Cause of Death; D005260:Female; D006090:Gram-Negative Bacteria / Q000145:classification / Q000302:isolation & purification*; D016905:Gram-Negative Bacterial Infections / Q000382:microbiology* / Q000401:mortality*; D017052:Hospital Mortality; D006801:Humans; D007362:Intensive Care Units; D008297:Male; D008480:Mediastinitis / Q000382:microbiology* / Q000401:mortality*; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology / Q000382:microbiology; D012189:Retrospective Studies
keywords: Antibiotherapy; Gram-negative bacteria; mediastinitis; mortality; outcome