title: Endotracheal tubes for critically ill patients: an in vivo analysis of associated tracheal injury, mucociliary clearance, and sealing efficacy.
abstract: BACKGROUND
  Improvements in the design of the endotracheal tube (ETT) have been achieved in recent years. We evaluated tracheal injury associated with ETTs with novel high-volume low-pressure (HVLP) cuffs and subglottic secretions aspiration (SSA) and the effects on mucociliary clearance (MCC).
  
  
  METHODS
  Twenty-nine pigs were intubated with ETTs comprising cylindrical or tapered cuffs and made of polyvinylchloride (PVC) or polyurethane. In specific ETTs, SSA was performed every 2 h. Following 76 h of mechanical ventilation, pigs were weaned and extubated. Images of the tracheal wall were recorded before intubation, at extubation, and 24 and 96 h thereafter through a fluorescence bronchoscope. We calculated the red-to-green intensity ratio (R/G), an index of tracheal injury, and the green-plus-blue (G+B) intensity, an index of normalcy, of the most injured tracheal regions. MCC was assessed through fluoroscopic tracking of radiopaque markers. After 96 h from extubation, pigs were killed, and a pathologist scored injury.
  
  
  RESULTS
  Cylindrical cuffs presented a smaller increase in R/G vs tapered cuffs (P = .011). Additionally, cuffs made of polyurethane produced a minor increase in R/G (P = .012) and less G+B intensity decline (P = .022) vs PVC cuffs. Particularly, a cuff made of polyurethane and with a smaller outer diameter outperformed all cuffs. SSA-related histologic injury ranged from cilia loss to subepithelial inflammation. MCC was 0.9 ± 1.8 and 0.4 ± 0.9 mm/min for polyurethane and PVC cuffs, respectively (P < .001).
  
  
  CONCLUSIONS
  HVLP cuffs and SSA produce tracheal injury, and the recovery is incomplete up to 96 h following extubation. Small, cylindrical-shaped cuffs made of polyurethane cause less injury. MCC decline is reduced with polyurethane cuffs.
authors.affiliation: Division of Animal Experimentation, Department of Pulmonary and Critical Care Medicine, Thorax Institute, Hospital Clínic, Barcelona, Spain; Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain; Centro de Investigación Biomedica En Red-Enfermedades Respiratorias (CIBERES), Barcelona, Spain.
authors.forename: Gianluigi
authors.initials: G
authors.lastname: Li Bassi
authors.affiliation: Division of Animal Experimentation, Department of Pulmonary and Critical Care Medicine, Thorax Institute, Hospital Clínic, Barcelona, Spain.
authors.forename: Nestor
authors.initials: N
authors.lastname: Luque
authors.affiliation: Division of Animal Experimentation, Department of Pulmonary and Critical Care Medicine, Thorax Institute, Hospital Clínic, Barcelona, Spain; Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain; Centro de Investigación Biomedica En Red-Enfermedades Respiratorias (CIBERES), Barcelona, Spain.
authors.forename: Joan Daniel
authors.initials: JD
authors.lastname: Martí
authors.affiliation: Division of Animal Experimentation, Department of Pulmonary and Critical Care Medicine, Thorax Institute, Hospital Clínic, Barcelona, Spain; Centro de Investigación Biomedica En Red-Enfermedades Respiratorias (CIBERES), Barcelona, Spain.
authors.forename: Eli
authors.initials: E
authors.lastname: Aguilera Xiol
authors.affiliation: Division of Animal Experimentation, Department of Pulmonary and Critical Care Medicine, Thorax Institute, Hospital Clínic, Barcelona, Spain; University of Milan, Milan, Italy.
authors.forename: Marta
authors.initials: M
authors.lastname: Di Pasquale
authors.affiliation: Division of Animal Experimentation, Department of Pulmonary and Critical Care Medicine, Thorax Institute, Hospital Clínic, Barcelona, Spain; University of Milan, Milan, Italy.
authors.forename: Valeria
authors.initials: V
authors.lastname: Giunta
authors.affiliation: Division of Animal Experimentation, Department of Pulmonary and Critical Care Medicine, Thorax Institute, Hospital Clínic, Barcelona, Spain.
authors.forename: Talitha
authors.initials: T
authors.lastname: Comaru
authors.affiliation: Division of Animal Experimentation, Department of Pulmonary and Critical Care Medicine, Thorax Institute, Hospital Clínic, Barcelona, Spain; Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain; Centro de Investigación Biomedica En Red-Enfermedades Respiratorias (CIBERES), Barcelona, Spain.
authors.forename: Montserrat
authors.initials: M
authors.lastname: Rigol
authors.affiliation: Division of Animal Experimentation, Department of Pulmonary and Critical Care Medicine, Thorax Institute, Hospital Clínic, Barcelona, Spain; University of Milan, Milan, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Terraneo
authors.affiliation: Division of Animal Experimentation, Department of Pulmonary and Critical Care Medicine, Thorax Institute, Hospital Clínic, Barcelona, Spain; University of Milan, Milan, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: De Rosa
authors.affiliation: Division of Animal Experimentation, Department of Pulmonary and Critical Care Medicine, Thorax Institute, Hospital Clínic, Barcelona, Spain.
authors.forename: Mariano
authors.initials: M
authors.lastname: Rinaudo
authors.affiliation: Division of Animal Experimentation, Department of Pulmonary and Critical Care Medicine, Thorax Institute, Hospital Clínic, Barcelona, Spain.
authors.forename: Ernesto
authors.initials: E
authors.lastname: Crisafulli
authors.affiliation: Division of Animal Experimentation, Department of Pulmonary and Critical Care Medicine, Thorax Institute, Hospital Clínic, Barcelona, Spain.
authors.forename: Rogelio Cesar
authors.initials: RC
authors.lastname: Peralta Lepe
authors.affiliation: Division of Animal Experimentation, Department of Pulmonary and Critical Care Medicine, Thorax Institute, Hospital Clínic, Barcelona, Spain; Division of Bronchoscopy, Department of Pulmonary Medicine, Thorax Institute, Hospital Clínic, Barcelona, Spain.
authors.forename: Carles
authors.initials: C
authors.lastname: Agusti
authors.affiliation: Division of Animal Experimentation, Department of Pulmonary and Critical Care Medicine, Thorax Institute, Hospital Clínic, Barcelona, Spain; Division of Bronchoscopy, Department of Pulmonary Medicine, Thorax Institute, Hospital Clínic, Barcelona, Spain.
authors.forename: Carmen
authors.initials: C
authors.lastname: Lucena
authors.affiliation: Division of Animal Experimentation, Department of Pulmonary and Critical Care Medicine, Thorax Institute, Hospital Clínic, Barcelona, Spain; Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain; Centro de Investigación Biomedica En Red-Enfermedades Respiratorias (CIBERES), Barcelona, Spain.
authors.forename: Miguel
authors.initials: M
authors.lastname: Ferrer
authors.affiliation: Division of Animal Experimentation, Department of Pulmonary and Critical Care Medicine, Thorax Institute, Hospital Clínic, Barcelona, Spain; Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain; Centro de Investigación Biomedica En Red-Enfermedades Respiratorias (CIBERES), Barcelona, Spain.
authors.forename: Laia
authors.initials: L
authors.lastname: Fernández
authors.affiliation: Division of Animal Experimentation, Department of Pulmonary and Critical Care Medicine, Thorax Institute, Hospital Clínic, Barcelona, Spain; Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain; Centro de Investigación Biomedica En Red-Enfermedades Respiratorias (CIBERES), Barcelona, Spain; University of Barcelona, Barcelona, Spain. Electronic address: atorres@clinic.ub.es.
authors.forename: Antoni
authors.initials: A
authors.lastname: Torres
mesh_terms: D000818:Animals; D016638:Critical Illness / Q000628:therapy*; D007442:Intubation, Intratracheal / Q000009:adverse effects* / Q000295:instrumentation*; D009079:Mucociliary Clearance; D013552:Swine; D014132:Trachea / Q000293:injuries* / Q000502:physiology*; D016896:Treatment Outcome