title: Description and microbiology of endotracheal tube biofilm in mechanically ventilated subjects.
abstract: BACKGROUND
  A biofilm is found on the inner side of endotracheal tubes (ETT) in mechanically ventilated patients, but its features and role in pneumonia remain unclear.
  
  
  METHODS
  This prospective, observational, monocentric study included critically ill ventilated subjects. Measurement of the ETT inner volume was first performed before extubation using the acoustic reflection method. After extubation, the biofilm was studied by means of optical and atomic force microscopy. Bacteriological analysis was then performed and compared with clinical documentation.
  
  
  RESULTS
  Twenty-four subjects were included. Duration of intubation lasted from 2 to 79 d (mean ± SD: 11 ± 15 d). The mean percentage of ETT volume loss evaluated in situ (n = 21) was 7.1% and was not linked with the duration of intubation. Analyses with atomic force microscopy (n = 6) showed a full coverage of the inner part of the tube with biofilm, even after saline rinse. Its thickness ranged from 0.8 to 5 μm. Bacteriological cultures of the biofilm (n = 22) often showed the same bacteria as in tracheal secretions, especially for pathogenic organisms. Pseudomonas aeruginosa and Candida albicans were among the most frequent microorganisms. In subjects who had experienced a successfully treated episode of ventilator-associated pneumonia (n = 5), the responsible bacteria were still present in the biofilm.
  
  
  CONCLUSIONS
  ETT biofilm is always present in intubated patients whatever the duration of intubation and appears quickly after intubation. Even after soft rinse, a small but measurable part of biofilm remains always present, and seems strongly adherent to the ETT lumen. It contains potentially pathogenic bacteria for the lung.
authors.affiliation: Service de réanimation médicale, Centre Hospitalier Universitaire (CHU) Henri Mondor, Créteil, France Unité Institut National de la Santé et de la Recherche Médicale (INSERM) U955, Fonctions Cellulaires et Moléculaires de l'Appareil Respiratoire et des Vaisseaux, Equipe Biomécanique Cellulaire et Respiratoire, Faculté de Médecine de Créteil, Paris 12, Créteil danin.pe@chu-nice.fr.
authors.forename: Pierre-Eric
authors.initials: PE
authors.lastname: Danin
authors.affiliation: Unité de Contrôle, Epidémiologie et Prévention de l'Infection, CHU Henri Mondor, Créteil.
authors.forename: Emmanuelle
authors.initials: E
authors.lastname: Girou
authors.affiliation: Laboratoire de bactériologie-virologie, CHU Henri Mondor, Créteil.
authors.forename: Patrick
authors.initials: P
authors.lastname: Legrand
authors.affiliation: Unité Institut National de la Santé et de la Recherche Médicale (INSERM) U955, Fonctions Cellulaires et Moléculaires de l'Appareil Respiratoire et des Vaisseaux, Equipe Biomécanique Cellulaire et Respiratoire, Faculté de Médecine de Créteil, Paris 12, Créteil.
authors.forename: Bruno
authors.initials: B
authors.lastname: Louis
authors.affiliation: Unité Institut National de la Santé et de la Recherche Médicale (INSERM) U955, Fonctions Cellulaires et Moléculaires de l'Appareil Respiratoire et des Vaisseaux, Equipe Biomécanique Cellulaire et Respiratoire, Faculté de Médecine de Créteil, Paris 12, Créteil.
authors.forename: Redouane
authors.initials: R
authors.lastname: Fodil
authors.affiliation: Département Anatomie pathologique, Unité INSERM U955, CHU Henri Mondor, Créteil, France.
authors.forename: Christo
authors.initials: C
authors.lastname: Christov
authors.affiliation: Service de réanimation médicale, Centre Hospitalier Universitaire (CHU) Henri Mondor, Créteil, France.
authors.forename: Jérôme
authors.initials: J
authors.lastname: Devaquet
authors.affiliation: Unité Institut National de la Santé et de la Recherche Médicale (INSERM) U955, Fonctions Cellulaires et Moléculaires de l'Appareil Respiratoire et des Vaisseaux, Equipe Biomécanique Cellulaire et Respiratoire, Faculté de Médecine de Créteil, Paris 12, Créteil.
authors.forename: Daniel
authors.initials: D
authors.lastname: Isabey
authors.affiliation: Service de réanimation médicale, Centre Hospitalier Universitaire (CHU) Henri Mondor, Créteil, France Unité Institut National de la Santé et de la Recherche Médicale (INSERM) U955, Fonctions Cellulaires et Moléculaires de l'Appareil Respiratoire et des Vaisseaux, Equipe Biomécanique Cellulaire et Respiratoire, Faculté de Médecine de Créteil, Paris 12, Créteil Keenan Research Centre, St Michael's Hospital, Toronto, and the Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Laurent
authors.initials: L
authors.lastname: Brochard
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018441:Biofilms; D002176:Candida albicans / Q000302:isolation & purification; D004866:Equipment Contamination; D005260:Female; D006801:Humans; D007442:Intubation, Intratracheal / Q000295:instrumentation*; D008297:Male; D018625:Microscopy, Atomic Force; D008875:Middle Aged; D053717:Pneumonia, Ventilator-Associated / Q000382:microbiology; D011446:Prospective Studies; D011550:Pseudomonas aeruginosa / Q000302:isolation & purification; D012121:Respiration, Artificial / Q000295:instrumentation*; D012122:Ventilators, Mechanical / Q000009:adverse effects / Q000382:microbiology*; D055815:Young Adult
keywords: biofilm; endotracheal tube; ventilator-associated pneumonia