title: The use of a novel cleaning closed suction system reduces the volume of secretions within the endotracheal tube as assessed by micro-computed tomography: a randomized clinical trial.
abstract: BACKGROUND
  Early after intubation, a layer of biofilm covers the inner lumen of the endotracheal tube (ETT). Cleaning the ETT might prevent airways colonization by pathogens, reduce resistance to airflow, and decrease sudden ETT obstruction. We investigated the effectiveness of a cleaning closed suction system in maintaining the endotracheal tube free from secretions.
  
  
  METHODS
  We conducted a single center, randomized controlled trial, in the general intensive care unit of a tertiary-level university hospital. We enrolled 40 adult critically ill patients expected to remain intubated for more than 48 h, within 24 h from intubation. Patients were randomized to receive three ETT cleaning maneuvers/day using a novel device (Airway Medix Closed Suction System™, cleaning group) or to standard care (no ETT cleaning, standard closed suction, control group). After extubation, the amount of secretions in the ETTs was measured by micro-computed tomography.
  
  
  RESULTS
  The volume of secretions in the ETTs from the cleaning group was lower than controls (0.081 [0.021-0.306] vs. 0.568 [0.162-0.756] mL, p = 0.001), corresponding to a cross-sectional area reduction six times lower (1[0-3] vs. 6 [2-10] %, p = 0.001). In a subset of 16 patients, the resistance to airflow tended to be lower after 1 day of treatment (p = 0.063) and was lower after 2 days (0.024), while no difference was present at enrollment (p = 0.922). ETT colonization did not differ between the two groups.
  
  
  CONCLUSIONS
  The use of a novel cleaning closed suction system proved to be effective in reducing secretions present in the ETT after extubation, possibly reducing resistance to airflow during intubation.
  
  
  BACKGROUND
  clinicaltrials.gov NCT01912105.
authors.affiliation: Department of Health Science, University of Milan-Bicocca, Via Cadore 48, Monza (MB), 20900, Italy. andrea.coppadoro@gmail.com.|A.Manzoni Hospital, Lecco, Italy. andrea.coppadoro@gmail.com.
authors.forename: Andrea
authors.initials: A
authors.lastname: Coppadoro
authors.affiliation: Department of Health Science, University of Milan-Bicocca, Via Cadore 48, Monza (MB), 20900, Italy. giacomo.bellani1@unimib.it.|Department of Anesthesia and Intensive Care, San Gerardo Hospital, Monza, Italy. giacomo.bellani1@unimib.it.
authors.forename: Giacomo
authors.identifier: http://orcid.org/0000-0002-3089-205X
authors.initials: G
authors.lastname: Bellani
authors.affiliation: Department of Health Science, University of Milan-Bicocca, Via Cadore 48, Monza (MB), 20900, Italy. alfio.bronco@gmail.com.
authors.forename: Alfio
authors.initials: A
authors.lastname: Bronco
authors.affiliation: Department of Anesthesia and Intensive Care, San Gerardo Hospital, Monza, Italy. a.lucchini@hsgerardo.org.
authors.forename: Alberto
authors.initials: A
authors.lastname: Lucchini
authors.affiliation: Laboratory of Microbiology, San Gerardo Hospital, Monza, Italy. s.bramati@hsgerardo.org.
authors.forename: Simone
authors.initials: S
authors.lastname: Bramati
authors.affiliation: Department of Health Science, University of Milan-Bicocca, Via Cadore 48, Monza (MB), 20900, Italy. vanessa.zambelli@unimib.it.
authors.forename: Vanessa
authors.initials: V
authors.lastname: Zambelli
authors.affiliation: Department of Anesthesia and Intensive Care, San Gerardo Hospital, Monza, Italy. r.marcolin@hsgerardo.org.
authors.forename: Roberto
authors.initials: R
authors.lastname: Marcolin
authors.affiliation: Department of Health Science, University of Milan-Bicocca, Via Cadore 48, Monza (MB), 20900, Italy. antonio.pesenti@unimib.it.|Department of Anesthesia and Intensive Care, San Gerardo Hospital, Monza, Italy. antonio.pesenti@unimib.it.
authors.forename: Antonio
authors.initials: A
authors.lastname: Pesenti
keywords: Biofilm; Cleaning closed suction system; Cross-sectional area; Endotracheal tube; Resistance to airflow; Secretion volume