Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Meta-Analysis
. 2024 Jun 12;19(6):e0304745.
doi: 10.1371/journal.pone.0304745. eCollection 2024.

Closed-loop oxygen control for critically ill patients--A systematic review and meta-analysis

Caroline Gomes Mól  1 , Aléxia Gabriela da Silva Vieira  1 , Bianca Maria Schneider Pereira Garcia  1 , Emanuel Dos Santos Pereira  1 , Raquel Afonso Caserta Eid  1 , Marcus J Schultz  2   3   4   5 , Ana Carolina Pereira Nunes Pinto  6 , Ricardo Kenji Nawa  1
Affiliations
Meta-Analysis

Closed-loop oxygen control for critically ill patients--A systematic review and meta-analysis

Caroline Gomes Mól et al. PLoS One. .

Abstract

Background: The impact of closed-loop control systems to titrate oxygen flow in critically ill patients, including their effectiveness, efficacy, workload and safety, remains unclear. This systematic review investigated the utilization of closed-loop oxygen systems for critically ill patients in comparison to manual oxygen titration systems focusing on these topics.

Methods and findings: A search was conducted across several databases including MEDLINE, CENTRAL, EMBASE, LILACS, CINAHL, LOVE, ClinicalTrials.gov, and the World Health Organization on March 3, 2022, with subsequent updates made on June 27, 2023. Evidence databases were searched for randomized clinical parallel or crossover studies investigating closed-loop oxygen control systems for critically ill patients. This systematic review and meta-analysis was performed following the Preferred Reporting Items for Systematic Review and Meta-analysis guidelines. The analysis was conducted using Review Manager software, adopting the mean difference or standardized mean difference with a 95% confidence interval (95% CI) for continuous variables or risk ratio with 95% CI for dichotomous outcomes. The main outcome of interest was the percentage of time spent in the peripheral arterial oxygen saturation target. Secondary outcomes included time for supplemental oxygen weaning, length of stay, mortality, costs, adverse events, and workload of healthcare professional. A total of 37 records from 21 studies were included in this review with a total of 1,577 participants. Compared with manual oxygen titration, closed-loop oxygen control systems increased the percentage of time in the prescribed SpO2 target, mean difference (MD) 25.47; 95% CI 19.7, 30.0], with moderate certainty of evidence. Current evidence also shows that closed-loop oxygen control systems have the potential to reduce the percentage of time with hypoxemia (MD -0.98; 95% CI -1.68, -0.27) and healthcare workload (MD -4.94; 95% CI -7.28, -2.61) with low certainty of evidence.

Conclusion: Closed-loop oxygen control systems increase the percentage of time in the preferred SpO2 targets and may reduce healthcare workload.

Trial registration: PROSPERO: CRD42022306033.

PubMed Disclaimer

Conflict of interest statement

MJS was the team leader of Research and New Technologies at Hamilton Medical AG, Bonaduz, Switzerland, from January 2022 until January 2023. The other authors declare no conflicts of interest. This does not alter our adherence to PLOS ONE policies on sharing data and materials. This does not alter our adherence to PLOS ONE policies on sharing data and materials.

Figures

Fig 1
Fig 1. Flow of trials through the review.
Abbreviations: CENTRAL = Cochrane Central Register of Controlled Trials; CINAHL = Cumulative Index to Nursing and Allied Health Literature; EMBASE = Excerpta Medica dataBASE; LILACS = Latin American the Caribbean Literature in Health Sciences; MEDLINE = Medical Literature Analysis and the Retrieval System Online; PICO = Patient Intervention Comparator Outcome.
Fig 2
Fig 2. Risk of bias of RCT included studies.
D1 = randomization process; D2 = deviations from the intended interventions; D3 = missing outcome data; D4 = measurement of the outcome; D5 = selection of the reported results. Abbreviations: ASV = adaptive support ventilation; ICU = intensive care unit; PSV = pressure support ventilation; O2 = Oxygen; RoB2 = cochrane risk of bias 2.0 tool for randomized clinical trials; SpO2 = peripheral oxygen saturation.
Fig 3
Fig 3. Risk of bias of crossover included studies.
D1 = randomization process; DS = bias arising from period and carryover effects; D2 = deviations from the intended interventions; D3 = missing outcome data; D4 = measurement of the outcome; D5 = selection of the reported result. Abbreviations: ASV = adaptive support ventilation; ICU = intensive care unit; FiO2 = fraction of inspired oxygen; HFNC = high-flow nasal cannula; PSV = pressure support ventilation; SpO2 = peripheral oxygen saturation.
Fig 4
Fig 4. Subgroup analyses of time spent in the SpO2 target based on pooled data from five studies of noninvasive devices and two studies of mechanical ventilation.
Abbreviations: CI = confidence interval; HFNC = high flow nasal cannula; i-ASV = INTELLiVENT-Adaptive Support Ventilation; SD = standard deviation.
Fig 5
Fig 5. Forest plot for workload of healthcare professionals.
Abbreviations: CI = confidence interval; HFNC = high flow nasal cannula; i-ASV = INTELLiVENT-Adaptive Support Ventilation; SD = standard deviation.
See this image and copyright information in PMC

References

    1. O’Driscoll BR, Howard LS, Earis J, Mak V, British Thoracic Society Emergency Oxygen Guideline Group, BTS Emergency Oxygen Guideline Development Group. BTS guideline for oxygen use in adults in healthcare and emergency settings. Thorax [Internet]. 2017;72:ii1–90. Available from: 10.1136/thoraxjnl-2016-209729. - DOI
    1. Petersson J, Glenny RW. Gas exchange and ventilation–perfusion relationships in the lung. Eur Respir J [Internet]. 2014. [cited 2022 Aug 24];44:1023–41. Available from: https://erj.ersjournals.com/content/erj/44/4/1023. doi: 10.1183/09031936.00037014 - DOI - PubMed
    1. Gilbert-Kawai ET, Mitchell K, Martin D, Carlisle J, Grocott MPW. Permissive hypoxaemia versus normoxaemia for mechanically ventilated critically ill patients. Cochrane Database Syst Rev [Internet]. 2014;CD009931. Available from: doi: 10.1002/14651858.CD009931.pub2 - DOI - PMC - PubMed
    1. de Jonge E, Peelen L, Keijzers PJ, Joore H, de Lange D, van der Voort PHJ, et al.. Association between administered oxygen, arterial partial oxygen pressure and mortality in mechanically ventilated intensive care unit patients. Crit Care [Internet]. 2008;12:R156. Available from: doi: 10.1186/cc7150 - DOI - PMC - PubMed
    1. Barbateskovic M, Schjørring OL, Russo Krauss S, Jakobsen JC, Meyhoff CS, Dahl RM, et al.. Higher versus lower fraction of inspired oxygen or targets of arterial oxygenation for adults admitted to the intensive care unit. Cochrane Database Syst Rev [Internet]. 2019;2019. Available from: doi: 10.1002/14651858.CD012631.pub2 - DOI - PMC - PubMed