Efficacy Study of a Novel Device to Clean the Endotracheal Tube

• Endotracheal Tube endoluminal residual volume [ Time Frame: At extubation (An expected average of 5 days) ] [ Designated as safety issue: No ]
  Implementing an original technique by Thomas, et al. (Interscience Conference on Antimicrobial Agents and Chemotherapy. 2006, San Francisco,CA. ICAAC06-A-2966-ASM), the investigators will measure the size of the inner lumen of each ETT using a high definition Computed Tomography (CT) imaging of the extubated ETTs with subsequent reconstruction and analysis by use of dedicated software. The whole ETT will be analyzed through hig-definition CT slices, with detection of the plastic-mucus-air interfaces resulting in multiple measurement of the ETT cross-sectional area (CSA). The investigators will calculate the luminal residual air volume, the total volume of mucus and all the associated measurements, such as lowest CSA. Comparing the volume of the used ETT to a blank clean same-size one, the investigators will also measure the relative loss of volume (%) due to mucus accumulation.
  
  

• ETT Microbiology [ Time Frame: At extubation (An expected average of 5 days) ] [ Designated as safety issue: No ]
  For each patient a quantitative culture will be obtained from the ETT after extubation. Secretions will be retrieved from the ETT after CT scan and quantitative standard cultures will be performed. Microbial molecular diversity analysis and antibacterial resistance patterns will also be studied.
  
  
• ETT microscopic imaging [ Time Frame: At extubation (An expected average of 5 days) ] [ Designated as safety issue: No ]
  Samples of the ETT will be collected and stored in glutaraldehyde for subsequent Scanned Electron Microscopy (SEM) and Confocal Microscopy (CM) analysis.
  
  
• In-vivo respiratory mechanics [ Time Frame: Three times a day (An expected average of 5 days) ] [ Designated as safety issue: No ]
  Data about respiratory mechanics will be obtained in both groups for each enrolled patient three times a day (q8 hours). These measurements are safe non-invasive. They will require the RT to register pressure, volume and flow parameters from the ventilator in use on the patient.
  
  
• User's feedback [ Time Frame: At extubation (An expected average of 5 days) ] [ Designated as safety issue: Yes ]
  To evaluate the feasibility and efficacy of the endOclear, the investigators will administer an anonymous questionnaire to the RTs who will use the device during the study. RTs will be asked to evaluate the device on three clinical issues: efficacy in cleaning the ETT of the endOclear, safety of the new maneuver, and feasibility for future intensive care unit implementation. Nurses assisting the procedure will be asked for their anonymous opinion too. Outside of this final survey, users will be instructed to timely report to the investigators any concern regarding safety of the device or adverse events.
  
  
• ETT weight gain [ Time Frame: At extubation (An expected average of 5 days) ] [ Designated as safety issue: No ]
  Weight gain of the ETT due to secretions will be measured by mean of a high precision laboratory scale.
  
  

After a few days of mechanical ventilation (MV), the lumen of the endotracheal tube (ETT) is coated with a thick bacterial biofilm, which is a potential source for bacterial colonization of the lower respiratory tract and ventilator-associated pneumonia (VAP). Accumulation of mucus/secretions on the interior of the ETT also effectively lowers the cross section of the ETT and increases significantly the work of breathing in intubated patients, who then require increased MV support, with prolonged intubation and ICU stay.

A primary goal for all ICUs is to shorten the time of MV, to decrease the incidence of ETT microbial colonization and ultimately VAP incidence. To meet this goal several airways technologies to maintain the ETT free from debris/bacteria have been developed in order to improve the current ventilator-liberation standards in intubated critically ill patients.

Based on preliminary laboratory, animal and clinical data, The investigators now wish to test the hypothesis that a novel commercially available ETT cleaning device can be effective in targeting two specific issues:

• Specific aim 1: To evaluate the mean difference in ETT luminal volume of ETTs cleaned with the novel cleaning device (EndOclear) vs. ETT cleaned in the standard manner.
• Specific aim 2: To determine whether ETTs cleaned with the novel device show a lower degree of microbial colonization for the entire period of mechanical ventilation.

Data about in-vivo respiratory mechanics measurements, microbial diversity and antibiotic resistance analysis, users' feedbacks and safety of the device will also be collected.

The investigators will conduct a clinical trial on 74 intubated patients randomized to receive standard ETT cleaning or cleaning with the EndOclear.