PONE-D-20-26498

Obesity and Smoking as Risk Factors for Invasive Mechanical Ventilation in COVID-19: a Retrospective, Observational Cohort Study

PLOS ONE

Dear Dr. Costa Monteiro,

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We look forward to receiving your revised manuscript.

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Giordano Madeddu

Academic Editor

PLOS ONE

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Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Yes

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2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: I Don't Know

Reviewer #2: Yes

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3. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: Yes

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4. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: Yes

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5. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: The goal of this study was to evaluate respiratory failure in COVID-19 and explore factors associated

with risk of invasive mechanical ventilation (IMV). A retrospective, observational cohort study of 112 inpatient adults diagnosed with COVID-19 was carried out. Data were manually extracted from electronic

medical records. Multivariable and Univariable regression were used to evaluate association between

baseline characteristics, initial serum markers and the outcome of IMV. It was determined that obesity, smoking history, and elevated inflammatory markers were associated with increased need for IMV in patients with COVID-19. These findings are of utmost importance given the current scenario.

Reviewer #2: In this study (PONE-D-20-26498), Monteiro and colleagues described a small sample (28), who needed endotracheal intubation and invasive mechanical ventilation, among 112 COVID-19 included in the analysis. The idea is interesting the paper is well written, however I have some considerations to explain. First of all they described that 28 patients out 47 admitted to the ICU were intubated, but they did not describe the criteria of intubation.

Could you describe the intubation criteria that you used, please?

Moreover they did not describe any severity score, i.e. APACHE II, SAPS II.

Could you add a severity score to understand better the severity of your population admitted to ICU, since your mortality rate was very low compared to other ICU?

Regarding mechanical ventilation, they described a setting of median PEEP level of 10-12 cmH2O in severe ARDS and P/F rati < 150, but they did not describe any data on plateau pressure, driving pressure or compliance of the respiratory system. Therefore how did you decide to set PEEP level? Could you you described better respiratory mechanics (plateau pressure, driving pressure, PEEPi, compliance of the respiratory system)? Which criteria did you consider to decide for prone positioning? Could you report the duration of mechanical ventilation?

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Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: No

Reviewer #2: Yes: Daniela Pasero

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Obesity and Smoking as Risk Factors for Invasive Mechanical Ventilation in COVID-19: a Retrospective, Observational Cohort Study

PONE-D-20-26498R1

Dear Dr. Costa Monteiro,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

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Kind regards,

Giordano Madeddu

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: All comments have been addressed

Reviewer #2: All comments have been addressed

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2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Yes

**********

3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

**********

4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: Yes

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5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: Yes

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6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: (No Response)

Reviewer #2: Congratulations,

the authors addressed all comments, and the manuscript is now suitable for acceptance.

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7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: Yes: Shama Ahmad

Reviewer #2: Yes: Daniela Pasero