Closed Endotracheal Suctioning Impact on Ventilator-Related Parameters in Obstructive and Restrictive Respiratory Systems: A Bench Study

Round 1

Reviewer 1 Report

Abstract "The change ventilator-related parameters are intently monitored in the patient whose pulmonary mechanic was compromised through the CSS endotracheal tube suctioning procedures in the clinical airway management." is unclear.

Introduction could be shortened. [e.g. Paragraph  - "The following points were identified." does not belong in the introduction].

How many replications of each experiment [please state]?

Figures 2-6 display repeated measurements and the statistical methods need to be appropriate.

 

Author Response

Editor-in-Chief Applied Sciences

Dear Reviewer 1:

Thank you for considering our manuscript titled “Closed Endotracheal Suctioning Impact on Ventilator-related Parameters in Obstructive and Restrictive Respiratory Systems: A Bench Study” by Jung Fang, et al. for the “Original Articles” division of your journal. Firstly, we would like to thank all the reviewers for critically examining this manuscript and providing many invaluable comments and suggestions. We have clarified/amended the issues raised by the reviewers in the revised manuscript. These changes can be founded in the highlighted section in the revised document. Within this e-mail, we also attached the documentation that indicates how we address each reviewers’ feedback.

 

We greatly appreciate your consideration of the revised manuscript.

 

Kind regards,

 

Guey-Mei Jow

School of Medicine, Fu-Jen Catholic University,

No.510, Zhongzheng Rd., Xinzhuang Dist., New Taipei City 24205, Taiwan.

Tel.: +886-2-2905-3424; Fax: +886-2-2905-2096

E-mail: 039666@mail.fju.edu.tw

Author Response File: Author Response.pdf

Reviewer 2 Report

Jung et al. conducted an in-vitro study aimed at evaluating the effect of closed endotracheal suctioning on ventilator parameters. In particular, they evaluated the effect of ventilation modality, respiratory mechanics, ETT and catheter sizes on PIP, minute ventilation, and PEEP. The topic is clinically relevant because suctioning is a frequent and important procedure in intubated patients. In particular, a recent consensus statement suggests the use of closed suction systems for the management of COVID-19 patients (Crit Care. 2021 Mar 16;25(1):106). Here below, you can find my specific comments.

1. The increase in PIP at the airways opening when the presence of a catheter increases the resistance on the tracheal tube is not necessarily associated with an increased risk of barotrauma. Indeed, there will be a higher pressure drop across the tracheal tube. If the mechanical properties of the system do not change, to deliver a given tidal volume, the driving pressure measured downstream the ETT will be the same. I suggest measuring the pressure downstream of the tracheal tube. If this is not possible, please consider the plateau pressure during VC-CMV and/or comment about the fact that an increased PIP measured at the inlet of the ETT does not necessarily result in increased pressure in the distal lung.
2. References to previous studies comparing closed and open suctioning systems are lacking, including Raimundo et al. Respir Care. 2021 May;66(5):785-792.; Crit Care Med. 2007 Jan;35(1):260-70.; Cochrane Database Syst Rev. 2007 Oct 17;2007(4):CD004581. Kuriyama et al. Intensive Care Med. 2015 Mar;41(3):402-11.
3. Lines 90-102: Please rephrase for clarity. Moreover, I do not agree that the increase in PIP during VC-CMV demonstrates the efficacy of closed suctioning.
4. Lines 121-123: Please specify the compliance used to simulate obstructive patients and the resistance used in the restrictive model.
5. Line 124: Did you use cuffed ETTs?
6. Lines 181-183: I would say that the increase in R_INSP was higher than the increase in R
7. Table 1: Please specify if mean and SD refer to the absolute values of RINSP and REXP or if they are the differences with and without the suctioning system in place. Add the units of measure, use two digits throughout the table, and specify where the significant differences are (results of the post-hoc test after ANOVA). Also, consider using a graph rather than a table to show the changes in resistance as a function of the test lung mechanical characteristics.
8. Figure 4 and Figure 5: Please consider comparing PEEP and Vexp with and without the suctioning system rather than between PC-CMV and VC-CMV.
9. Discussion: please speculate about the role of different flow regimes in determining different changes in resistance between inspiration vs expiration and between VC-CMV vs PC-CMV

Author Response

Editor-in-Chief Applied Sciences

Dear Reviewer 2:

Thank you for considering our manuscript titled “Closed Endotracheal Suctioning Impact on Ventilator-related Parameters in Obstructive and Restrictive Respiratory Systems: A Bench Study” by Jung Fang, et al. for the “Original Articles” division of your journal. Firstly, we would like to thank all the reviewers for critically examining this manuscript and providing many invaluable comments and suggestions. We have clarified/amended the issues raised by the reviewers in the revised manuscript. These changes can be founded in the highlighted section in the revised document. Within this e-mail, we also attached the documentation that indicates how we address each reviewers’ feedback.

 

We greatly appreciate your consideration of the revised manuscript.

 

Kind regards,

 

Guey-Mei Jow

School of Medicine, Fu-Jen Catholic University,

No.510, Zhongzheng Rd., Xinzhuang Dist., New Taipei City 24205, Taiwan.

Tel.: +886-2-2905-3424; Fax: +886-2-2905-2096

E-mail: 039666@mail.fju.edu.tw

Author Response File: Author Response.pdf