Outcomes and Functional Deterioration in Hospital Admissions with Acute Hypoxemia

Round 1

Reviewer 1 Report

Intriguing study, but I am not sure what would be the clinical implication of this study (if any). The role of permissive hypoxia in adult patients is still not defined. Yes, we should to avoid hyperoxia but multiple large population based studies have shown no change in outcomes when using high vs low (90-94%) SpO2 targets. some limitations of this trial which should be highlighted 

1. Only 58 patients had room air SpO2 recorded. so we can't be sure that others were "truly hypoxic"

2. 33% with hypercapnic respiratory failure so some of these patients could be chronically hypxemic which is not diagnosed at the time of ER presentation and significant number had COPD which does impact the functional outcomes

3. similarly majority of the patients were old which are more prone to have functional deterioration but necessarily due to hypoxemia.

Author Response

Please see the attachment

Author Response File: Author Response.pdf

Reviewer 2 Report

This is a prospective observational study on admissions with a new need for oxygen therapy. The design conducted across two centers enhances the study's robustness and credibility.

Addressing functional outcomes makes sense because it provides new insights into the impact of medical interventions on patients' lives. 

They reflect patients' abilities to perform activities essential for independent living and are clinically relevant. 

Despite the main finding of the study that patients with new onset hypoxemia at admission are less functional at discharge is of interest the reviewer has some major comments:

1.    Authors should comment on why patient with cancer and those with good functional status on admission were more frequently experiencing a function decline.

2.    It is stated that patients on LTOT were excluded. What consideration given to patients using supplemental O2 on exertion during the day or at night?

3.    How was the functional status 4 weeks prior to admission objectivated? Did that depend on patient's recall or history taken via caregivers or relatives?

4.    The continued need for supplemental O2 therapy in those patients (29%) who were started on LTOT on hospital discharge should be evaluated a few weeks after discharge. The authors should comment on this.

5.    Lack of Follow-up: Patients were not followed up after discharge, which limits understanding of long-term functional outcomes and recovery patterns. Although this cannot be changed retrospectively it should be mentioned as a limitation.

6.    The use of the WHO scale, while standardized and straightforward, might not capture the full complexity of functional status compared to more detailed tools like the activity of daily living (ADL) index or even the Clinical Frailty Scale (CFS). The complexity of recording the functional status was not made clear by this tool, e.g. the ADL-scale or CFS could have helped to get a better assessment of the functional status. This should be incorporated in a mentioned future interventional study as an endpoint and should be added to the outlook section of the discussion.

Minor comments:

1.    In the section on treatment (p.5) first paragraph (lines 152-160) please give percentages of patients (n=115 and n=58) and the 25 and 75% percentiles of SpO2.

2.    In the section on outcome first paragraph (line 164-169) please give percentages of patients (n=3, n=8 and n=5).

3.    Please correct type area in table 2 (e.g. line #4 and #10). Typo footnote (line 173) combinations are possible.

Author Response

Please see the attachment

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

no further comment