The Mechanical Power in Patients with Acute Respiratory Distress Syndrome Undergoing Prone Positioning Can Predict Mortality

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

I read with great interest the paper by Chang et al regarding the effect of mechanical power to mortality in patients with ARDS. The main purpose of this study was to expand the importance of the delivered mechanical power on the outcome in patients undergoing prone positioning. In my opinion the major  disadvantage of the study is that mechanical ventilation was administered in pressure control mode, but I believe that the results are still valuable. In my opinion there are some points that need more clarifications:

- Table 1. The data presented were collected at admission or at the day that the patients underwent prone positioning?

- Lines 199-204. The comparison was between which groups? All the patients before and after prone positioning? The data do not match to the data presented in Table 2.

- It would be of great interest if PaO2/FiO2 ratio and pH and/or CO2 was available for each group of patients in Table 2.

- Lines 222-223. The statement that MP etc did not differ before and after prone positioning refers to which groups of patients? Accordind to the Table 2 there are statistically significant differences between the groups.

- It has to be clear that the increase in MP, MP/BMI and MP/compliance for the non-survivors may be evolution of the disease and not a consequence of prone positioning. A comparison of the above mentioned characteristics before and immediately after proning would be very interesting if data were available, since the changes would be attributed to prone positioning exclusively.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

Dear author, 

You present an interesting work. I would like to make a series of remarks with respect to it, with the intention of improving it. 

You indicate following the strobe guide, but there are aspects that have not been implemented. I suggest that if it cannot be adjusted to this guide, remove it from the text.

Regarding the title, I would change the title. I would eliminate the term “optimization of infection control”, and leave only the rest of the title, to fit the reality of the stated objectives. 

Include the type of study in the title.

The justification is limited. Please implement it, with aspects that are addressed in your work, such as adherence to practices by nurses, especially in their socio-economic context.

Regarding the objectives, although they are three plausible objectives, I would not disintegrate them; I would unite them at a syntactic level in a subordinate sentence or in the same paragraph. I would look for a nexus of union through the lexicon. 

 

Eliminate research questions. Include the rationale and justification of the study in the introductory section.

You indicate that the participating subjects should present, as a criterion for inclusion, an update of knowledge, how was this update ensured? Is any specific training required? Who provides it? What is considered updated? What is the period of time to lose the update? Define this aspect.

Indicate that you conducted a purposive, convenience sampling. Indicate how you selected the participants. 

Regarding the calculation of the selected sample, if the ICU population you indicate is 184 nurses, how can it be that you selected 190, to finally be left with 165, as indicated by the statistical calculation? Statistical power is commonly used in experimental or quasi-experimental or analytical research works, where it is intended to see the effect of variables on populations, manipulated or not, using Anova as a statistic,... It does not make sense to use it in a descriptive-observational study. 

In any case, the calculations for sample in known population are lower than what you indicate and for the type of study. However, that is not a bad thing. You should review the rationale, and argue adequately for this calculation, since errors can be seen. 

 

The study you use as reference for your knowledge questionnaire (Getahun et al.2022), does not provide metric properties; in fact, you use as reference for your instrument three other works (one of them not related to the subject of study), this work was used in Ethiopia, with the characteristics of this socio-cultural environment.

Please indicate these peculiarities as properties of your instrument. 

Regarding the second instrument, please indicate how the observational grid was developed and its metric properties, if any, such as inter-observer variability. It also points out that the study on which it is based is a systematic review of knowledge, which gathers the available evidence and at no time proposes a checklist for verification of behavior in relation to good practices in mechanical ventilation. 

There are studies that do present this type of tools, and which are validated. Please locate them and mention them. 

 

What was the statistical treatment of the data provided? Can you indicate the methodological plan to be followed to analyze the variables to be measured?

The evidence used is poorly referenced. It does NOT use the vancouber standard. And it is scarce in number. 

The conclusions do not reflect the results, and present value judgments. 

Author Response

We thank the reviewer for the valuable comments. However, it seems that the comments did not apply to our study. The reviewer suggested we modify the title, but the title is different from my study. Also, other comments are not relevant to our study, such as the comments about nurses or Ethiopia.

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

I have no further remarks

Author Response

We thank the reviewer for pointing out these valuable comments.

Reviewer 2 Report

Comments and Suggestions for Authors

dear author, 

thank you for your work.

I would like to make a series of comments on your work, which I believe should be addressed.

You present a multicenter study, and collect data with retrospective character, in two different countries: 2015-2016 in eight centers in Taiwan and from 2017-2023 in one center in China.

The type inside is the same; the health care provided in all centers is the same..., the difference between countries, implies a difference in the care provided? 

Is the volume of patients selected proportional to the size and capacity of the centers?

Have you disaggregated the data by the type of center where they are treated?

Have you included patients seen during the Covid period, given the dates it appears that you have.

The results show that patients with a worse APACHE severity index and more serious pathologies die, which is to be expected. It demonstrates the existence of a relationship, but not the direction of this relationship. Could you contribute something original to this field?

Author Response

Please see the attachment.

Author Response File: Author Response.pdf