Evidence map›Paper›PMID 40876958›Full record

Observational studyBMJ open respiratory research2025

Use of carbon dioxide production to detect bacterial superinfections in mechanically ventilated patients with acute respiratory distress syndrome: an exploratory prospective cohort study.

Nicole S Strickler, Daniel A Hofmaenner, Reto A Schuepbach, Thomas C Scheier, Philipp K Buehler, Jukka Takala, Silvio D Brugger, Pascal M Frey

Registry-linked trialAbstract readObservational Study
In one paragraph

Observational study in BMJ open respiratory research, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. It is linked to trial NCT04410263 (Microbiota in COVID-19 Patients for Future Therapeutic and Preventive Approaches), which is not on this map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

NCT04410263 unknown statusnot on this map

Microbiota in COVID-19 Patients for Future Therapeutic and Preventive Approaches

TypeobservationalSponsorUniversity of ZurichRan2020 to 2023Enrolled300ConditionsCorona Virus Infection, ARDS, CoinfectionArmsSampling (EDTA blood, pharyngeal and nose swabs, bronchoalveolar lavage ,urine)
3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

8 authors.

Nicole S StricklerDepartment of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, Zurich, Switzerland.
Daniel A HofmaennerInstitute of Intensive Care, University Hospital Zurich, Zurich, Switzerland.
Reto A SchuepbachInstitute of Intensive Care, University Hospital Zurich, Zurich, Switzerland.
Thomas C ScheierDepartment of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, Zurich, Switzerland.
Philipp K BuehlerInstitute of Intensive Care, University Hospital Zurich, Zurich, Switzerland.
Jukka TakalaUniversity of Bern, Bern, Switzerland.
Silvio D Brugger *Department of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, Zurich, Switzerland.ORCID http://orcid.org/0000-0001-9492-9088
Pascal M Frey *Department of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, Zurich, Switzerland pascal.frey@insel.ch.ORCID http://orcid.org/0000-0001-6161-0919

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundBacterial superinfections are common in patients with acute respiratory distress syndrome (ARDS) but diagnosing them is challenging. Exhaled carbon dioxide (V'CO2) may be increased during bacterial infection, suggesting a potential marker for detecting bacterial superinfections in ARDS patients.

methodsIn a prospective cohort study of mechanically ventilated adult patients with ARDS due to SARS-CoV-2 in a tertiary intensive care unit, we assessed V'CO2 measurements from continuous volumetric capnography and calculated daily median V'CO2 levels. The primary outcome was to determine if a first substantial increase in daily median V'CO2 was associated with a first bacterial superinfection. Protocolised microbiological sampling and adjudicated clinical interpretations were used to determine the onset of a first superinfection.

resultsA total of 150 days of continuous volumetric capnography were analysed in 31 mechanically ventilated adult patients with ARDS due to SARS-CoV-2. We observed 10 patients (32%) with a first episode of substantial increase of daily median V'CO2, and 12 (39%) patients with a first bacterial superinfection. A V'CO2 increase was not associated with a superinfection on the same day (OR 3.47, 95% CI 0.64 to 18.92, p=0.15, adjusted for age and gender). Investigating all 150 test days of median V'CO2 revealed a poor sensitivity (17%, 95% CI 2% to 48%) for detecting superinfections. However, a first V'CO2 increase indicated superinfection with high specificity (94%, 95% CI 89% to 98%). Patients with superinfections showed higher daily median V'CO2 levels (210 mL/min) than those without (176 mL/min, p<0.001), even after adjusting for age and gender (OR 1.56, 95% CI 1.16 to 2.08, p=0.003).

conclusionsA sudden increase in daily median V'CO2 did not reliably detect bacterial superinfections, which was reflected in a poor sensitivity and inability to rule out superinfections in patients without V'CO2 increase. Nevertheless, high specificity suggests that V'CO2 may be useful to rule in superinfections in patients with ARDS. TRIAL REGISTRATION NUMBER: NCT04410263.

Indexed as

Bacterial InfectionsCarbon DioxideCOVID-19Respiration, ArtificialRespiratory Distress SyndromeSuperinfectionAdultAgedBreath TestsCapnographyFemaleHumansMaleMiddle AgedProspective StudiesSARS-CoV-2Carbon DioxideARDSBacterial InfectionCOVID-19Critical CarePneumoniaRespiratory Infection

Identifiers

PMID40876958
PMCPMC12410624

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.