PONE-D-22-01880Optimal Duration of the Apnea Test for Determining Brain Death: Benefit of the Short-Term Apnea TestPLOS ONE

Dear Dr. Hong,

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Steven Eric Wolf, MD

Academic Editor

PLOS ONE

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Reviewers' comments:

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Reviewer #1: Yes

Reviewer #2: Yes

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

Reviewer #1: Yes

Reviewer #2: Yes

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Reviewer #1: Yes

Reviewer #2: Yes

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Reviewer #1: Yes

Reviewer #2: Yes

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5. Review Comments to the Author

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Reviewer #1: Overall well written manuscript, addresses a clinically important issue for which a significant amount of controversy exists.

Only a few suggestions:

1. Clarify in the result section and Table #1, when describing most common causes of brain death "Traumatic hemorrhage" and "Non traumatic hemorrhage". Please clarify that these are intracranial hemorrhages or describe appropriately

2. Unclear if within 5 minutes all patients had a PaCO2 above 60 mmHg. If that is the case, state that all patients achieve this goal. If not, stare the percent that did.

Reviewer #2: A standard time interval for the apnea test has been suggested by national societies but not formalized by the international medical community. This paper is an attempt at starting that process, but because of varying ethical and legal standards, one paper will not complete the process. The scientific and statistical methods used by the authors are sound and are supported by the provided data. The choice of the smallest time interval that is satisfactory from a PaCO2 endpoint for protection of organs for transplantation is understandable but may be hard to achieve consensus. The additional time suggested by the American Academy of Neurology should not incur too great an oxygen debt or acidemia. As shown by this paper, the hemodynamics are usually easily controlled with vasoactive infusions. Some patients will in fact have intact brainstem reflexes that were not appreciated until the apnea test. Before the patient is declared dead, physicians still owe them a fiduciary duty. As suggested in this paper, future work should also focus on standardizing the balance of the protocol of the apnea test. The presented protocol is reasonable if the additional time is added.

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Reviewer #1: No

Reviewer #2: Yes: J. Sean Funston, M.D.

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Optimal Duration of the Apnea Test for Determining Brain Death: Benefit of the Short-Term Apnea Test

PONE-D-22-01880R1

Dear Dr. Hong,

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.

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Kind regards,

Steven Eric Wolf, MD

Academic Editor

PLOS ONE

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