Automatic oxygen titration with O2matic® to patients admitted with COVID-19 and hypoxemic respiratory failure

Ejvind Frausing Hansen, Charlotte Sandau Bech, Jørgen Vestbo, Ove Andersen, Linette Marie Kofod, Ejvind Frausing Hansen, Charlotte Sandau Bech, Jørgen Vestbo, Ove Andersen, Linette Marie Kofod

Abstract

Introduction: Patients with coronavirus disease (COVID-19) and pneumonitis often have hypoxemic respiratory failure and a need of supplementary oxygen. Guidelines recommend controlled oxygen, for most patients with a recommended interval of SpO2 between 92 and 96%. We aimed to determine if closed-loop control of oxygen was feasible in patients with COVID-19 and could maintain SpO2 in the specified interval.

Methods: Patients were prospectively enrolled in an observational study on a medical ward dedicated to patients with COVID-19. Closed-loop controlled oxygen was delivered by O2matic® which can deliver 0-15 liters/min and adjusts flow every second based on 15 seconds averaging of SpO2 measured by pulse oximetry. Lung function parameters were measured at admission.

Results: Fifteen patients (six women, nine men) participated in the study. Average age was 72 years. Lung function was severely impaired with FEV1, FVC and PEF reduced to approximately 50%. The average stay on the ward was 3.2 days and O2matic was used on average for 66 hours, providing 987 hours of observation. O2matic maintained SpO2 in the desired interval for 82.9% of the time. Time with SpO2 > 2% below interval was 5.1% and time with SpO2 > 2% above interval was 0.6%.

Conclusion: Closed-loop control of oxygen to patients with COVID-19 is feasible and can maintain SpO2 in the specified interval in the majority of time. Closed-loop automated control could be of particular benefit for patients in isolation with decreased visibility, surveillance and monitoring. Further studies must examine the clinical benefits.

Keywords: COVID-19; closed-loop; hypoxemia; lung function; oxygen saturation; oxygen therapy; titrated oxygen.

Conflict of interest statement

EFH is one of the inventors of O2matic® and have participated in the development and testing of the device since 2011. The partnership, which was built during the development funded by Innovation Fund Denmark, formed a new company (O2matic Ltd., Herlev, Denmark) in which EFH is shareholder. CSB and LMK do research involving O2matic, which is partly funded by Innovation Fund Denmark. The authors report no other conflicts of interest in this work.

© 2020 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.

Figures

Figure 1.
Figure 1.
The O2matic closed-loop oxygen controller.
Figure 2.
Figure 2.
O2matic profiles according to initial oxygen need.
Figure 3.
Figure 3.
Distribution of SpO2 values in target and outside target.

References

    1. Cornet AD, Kooter AJ, Peters MJL, et al. The potential harm of oxygen therapy in medical emergencies. Crit Care. 2013;17:313.
    1. Smith JL. The pathological effects due to increase of oxygen tension in the air breathed. J Physiol. 1899;24:19–8.
    1. Chu DK, Kim LH, Young PJ, et al. Mortality and morbidity in acutely ill adults treated with liberal versus conservative oxygen therapy (IOTA): a systematic review and meta-analysis. Lancet. 2018;391:1693–1705.
    1. Girardis M, Busani S, Damiani E, et al. Effect of conservative vs conventional oxygen therapy on mortality among patients in an intensive care unit: the oxygen-ICU randomized clinical trial. JAMA. 2016;316:1583–1589.
    1. O’Driscoll BR, Howard LS, Earis J, et al. British thoracic society emergency oxygen guideline group. BTS guideline for oxygen use in adults in healthcare and emergency settings. Thorax. 2017;72(Suppl1):ii1–ii90.
    1. Barrot L, Asfar P, Mauny F, et al. LOCO2 investigators and REVA research network. Liberal or conservative oxygen therapy for acute respiratory distress syndrome. N Engl J Med. 2020;382:999–1008.
    1. Alhazzani W, Møller MH, Arabi YM, et al. Surviving Sepsis Campaign: guidelines on the management of critically ill adults with Coronavirus Disease 2019 (COVID‑19). Intensive Care Med. 2020. DOI:10.1007/s00134-020-06022-5.
    1. Lellouche F, Bouchard PA, Roberge M, et al. Automated oxygen titration and weaning with FreeO2 in patients with acute exacerbation of COPD: a pilot randomized trial. Int J Chron Obstruct Pulmon Dis. 2016;11:1983–1990.
    1. L’Her E, Dias P, Gouillou M, et al. Automatic versus manual oxygen administration in the emergency department. Eur Respir J. 2017;50:1602552.
    1. Hansen EF, Hove JD, Bech CS, et al. Automated oxygen control with O2matic during admission with exacerbation of COPD. Int J Chron Obstruct Pulmon Dis. 2018;13:3997–4003.
    1. Sturrock S, Williams E, Dassios T, et al. Closed loop automated oxygen control in neonates-a review. Acta Paediatr. 2020;109:914–922.
    1. Gupta A, Madhavan MV, Sehgal K, et al. Extrapulmonary manifestations of COVID-19. Nature Med. 2020. DOI:10.1038/s41591-020-0968-3.
    1. Gattinoni L, Chiumello D, Caironi P, et al. COVID-19 pneumonia: different respiratory treatments for different phenotypes? Intensive Care Med. 2020;46:1099–1102.
    1. Gattinoni L, Coppola S, Cressoni M, et al. COVID-19 does not lead to a “typical” acute respiratory distress syndrome. Am J Respir Crit Care Med. 2020;201:1299–1300.
    1. Israelsen SB, Kristiansen KT, Hindsberger B, et al. Characteristics of patients with COVID-19 pneumonia at Hvidovre Hospital, March-April 2020. Dan Med J. 2020;67:A05200313.
    1. Marini JJ, Gattinoni L. Management of COVID-19 respiratory distress. JAMA. 2020. DOI:10.1001/jama.2020.6825
    1. Hedley-Whyte J. Pulmonary oxygen toxicity: investigation and mentoring. Ulster Med J. 2008;77:39–42.
    1. Moccia F, Gerbino A, Lionetti V, et al. COVID-19-associated cardiovascular morbidity in older adults: a position paper from the Italian society of cardiovascular researches. Geroscience. 2020;42:1021–1049
    1. Mo X, Jian W, Su Z, et al. Abnormal pulmonary function in COVID-19 patients at time of hospital discharge. Eur Respir J. 2020;55:2001217.

Source: PubMed

Sponsorer og samarbeidspartnere

Medisinsk tilstand

Legemiddelintervensjoner

3
Abonnere