PONE-D-21-08611

Does Perioperative Respiratory Event Increase Length of Hospital Stay and Hospital Cost in Pediatric Ambulatory Surgery?

PLOS ONE

Dear Dr. Oofuvong,

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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

Reviewer #3: Yes

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

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: 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

Reviewer #3: 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

Reviewer #3: 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 authors present a subgroup analysis of a single-institution, 13-month prospective cohort study of the effects of a perioperative respiratory event (PRE) on length of stay and hospital cost, in children having ambulatory surgery. Of note, the authors' ref. [7] is their prior study that focused mostly on inpatients, and they state that the purpose of this manuscript's subgroup analysis is to investigate these effects on ambulatory pediatric surgery patients.

The authors employ directed acyclic graphs to determine which variables to include in their multivariable regression models. They then find that PREs with unplanned admission were associated with an increased length of stay and increased hospital cost.

The paper is a reasonable extension of the authors' prior work. There are some issues that should be addressed before publication:

1. The authors' explanation of the calculation of the contribution margin (lines 126-140) is not clear. It seems that they use the equation

(contribution margin) = 0.6 x (hospital charges)

based on assumptions from their prior work. This discussion should be clarified, as this calculation seems to be critical to one of the main conclusions - that increased costs to patients were associated with PRE.

2. Why are there so few general surgery procedures reported? The procedures in Table 4 include ophthalmology, otolaryngology, urology and gastroenterology procedures. While excision of superficial mass and hydrocelectomy (which often includes inguinal hernia repair) are included, the authors should comment on this. I would expect there to be ambulatory hernia repairs, cholecystectomies, gastrostomy placements, and the like.

3. The results from this study should be compared in more detail to those of the authors' ref. [7] in the Discussion.

4. The manuscript needs to be proofread again.

Reviewer #2: It is an interesting paper that provides information on little-studied aspects of ambulatory surgery in children.

I am struck by the fact that 27.1% of the patients were eliminated for not being able to contact their parents/guardians. Seems too high for ambulatory procedures where children get to the hospital accompanied by someone.

It would be convenient for the authors to explain their thinking about the relationship between PRE and the ASA classification of patients.

Line 217 has some writing problems.

On line 332 the authors write about the excess hospital cost. Here, it seems to me that the variables medications and oxygen therapy should not be included in the paragraph because both variables did'n reach statistical significance.

Statistically it has some tables that are difficult for the regular reader to understand, but they are finally understood with the specifications of each table.

Reviewer #3: This is an important paper despite no surprising findings. I have almost none criticism; the number of partcipiants seems short to overcome the effect of so many covariables. Try to use more accessible and simpler language. What is the explanation for a lower odds ratio in case of unplanned admission and non-PRE? The inclusion of "planned admission" may question the external validity of the conclusions. Is it possible to apply the same methodology excluding "planned" admissions", a more ubiquitous reality in pediatric ambulatory surgical centers?

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Reviewer #1: No

Reviewer #2: No

Reviewer #3: No

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Does Perioperative Respiratory Event Increase Length of Hospital Stay and Hospital Cost in Pediatric Ambulatory Surgery?

PONE-D-21-08611R1

Dear Dr. Oofuvong,

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,

Tai-Heng Chen, M.D.

Academic Editor

PLOS ONE

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

Reviewer #3: 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: (No Response)

Reviewer #3: Yes

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

Reviewer #1: Yes

Reviewer #2: (No Response)

Reviewer #3: Yes

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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: (No Response)

Reviewer #3: 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: (No Response)

Reviewer #3: 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: All my concerns have been met:

1. Authors clarified the calculation of contribution margin.

2. Authors clarified how surgical cases were classified as well as the pattern of general surgery cases at their institution.

2. Authors expanded discussion of the relation of the current work to their prior study.

4. Authors had the manuscript proofread by a native English speaker for clarity.

Reviewer #2: My previous comments have been answered with all satisfaction and it seems to me that, for my part, it can be published, although there are still flaws in the writing in English.

Reviewer #3: Despite the aa have failed to explain the rationale for a lower odds ratio in case of unplanned admission and non-PRE, I have no additional crticism. So "it is better to operate on unplanned admissions".

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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: No

Reviewer #2: Yes: Eduardo Bracho-Blanchet

Reviewer #3: No