Commentary on “Effect of the endOclear ® Device on Biofilm in Endotracheal Tubes”

2. There were 20 patients in the endOclear^® group with an average length of intubation of 5.75 days. No patient was intubated less than 24 hours. Therefore total days of intubation in the endOclear^® group were115. If one removes one day per patient (20 patients = 20 days) from the 115 days of ventilation in the endOclear^® group (as the device was not used in the first 24 hours) that leaves 95 days during which one endOclear^® device per day should have been used according to the study protocol. The authors report that only 43 endOclear^® procedures were performed. That means that 52 additional endOclear^® tube cleaning procedures should have been done in the study group. Conclusions regarding daily use of the endOclear^® device in these intubated patients are invalid.

3. No information is given on the mode of ventilation in use when pre- and post-endOclear^® ET Tube cleaning measurements were made. To combine all pre- and post-endOclear^® use measurements without assessing for ventilation mode may obfuscate any conclusions.

4. The authors state that post-procedure measurements were taken immediately after the cleaning procedure. Manipulation of the endotracheal tube may result in coughing, anxiety, and changes in physiologic parameters. Patient status following an endOclear^® tube cleaning procedure, certainly to compare pre- and post-values, should have been assessed after the patient had recovered, calmed down, and returned to their pre-procedure level of physiology and comfort.

5. No information was given as to the time passing between an endOclear^® tube clearing procedure and extubation. In relation to the study this is important for two reasons. First, if an endotracheal tube is cleaned and the patient is not extubated for 12, 24, or 36 hours it is not surprising that evaluation of the tube at extubation would show recurring and progressive stage maturation of the biofilm.

6. Second, the issue of elapsed time between endOclear^® use and SBT is also a significant question. If the endotracheal tube is cleaned with an endOclear^® device and the patient does not immediately undergo an SBT, then increased resistance and work of breathing would likely occur as secretions re-accumulate. Our recommended protocol is to use the device immediately prior to the SBT.

7. 24 of the 43 endOclear^® procedures resulted in more than one cc of secretions removed from the endotracheal tube. From data presented at AARC 2014, researchers reported that “This study shows that as little as one (1) ml of secretions can have a profound effect on the airway resistance of the endotracheal tube during mechanical ventilation (AARC 2014, Presentation 2018530, “Effects of Different Amounts of Artificial Secretions on the Airflow Resistance of Adult Endotracheal Tubes”). The authors here characterize the changes in resistance as “minute,” but do not give us the average starting resistances, the percentage change in resistance post procedure, or the actual statistical analysis of the change.

8. The authors state “One US FDA – approved device is the endOclear^®.” This is inaccurate. The endOclear^® Restore^(TM) is listed with the FDA as a Class 1 510K exempt device.

9. The authors state “After rinsing this cut section in 0.9% physiologic saline both the inner and outer lumens of the ET tube were scraped.” Hopefully the authors mean that the inner and outer curvatures of the ET Tube lumen were scraped. If microbiota from outside the ET Tube were mixed with the scrapings from the inside of the ET Tube for analysis it is hard to understand how any of the microbiologic findings have value concerning the potential benefits of cleaning the inside of endotracheal tubes.

10. Lastly, the authors should comment on the exceptionally high incidence of VAP in all of their intubated patients. This fact alone may negate many of the conclusions regarding the effect of the endOclear^® device on VAP in this small study.