Effects of CPAP and FiO2 on respiratory effort and lung stress in early COVID-19 pneumonia: a randomized, crossover study

Annals of Intensive Care

Research

Giacomo Bellani¹  Andrea Laguzzi²  Roberto Penso²  Luca Davicco²  Matteo Maria Macrì²  Salvatore Di Blasi²  Pietro Caironi³  Vincenzo Russotto³  Patrick Duncan Collins⁴  Lorenzo Giosa⁵  Luigi Camporota⁵  Alberto Perboni⁶  Martina Sciolla⁶  Fabiana Gorgonzola⁶  Massimo Muraccini⁷  Irene Steinberg⁸  Francesca Cerrone⁹ 

[1] Centre for Medical Sciences - CISMed, University of Trento, Trento, Italy;Department of Anesthesia and Intensive Care, Santa Chiara Regional Hospital, APSS Trento, Trento, Italy;Department of Anesthesia and Critical Care, AOU S. Luigi Gonzaga, Orbassano, Turin, Italy;Department of Anesthesia and Critical Care, AOU S. Luigi Gonzaga, Orbassano, Turin, Italy;Department of Oncology, University of Turin, Turin, Italy;Department of Critical Care Medicine, Guy’s and St. Thomas’ National Health Service Foundation Trust, St. Thomas’ Hospital, Westminster Bridge Road, SE17EH, London, UK;Department of Critical Care Medicine, Guy’s and St. Thomas’ National Health Service Foundation Trust, St. Thomas’ Hospital, Westminster Bridge Road, SE17EH, London, UK;Centre for Human and Applied Physiological Sciences, School of Basic and Medical Biosciences, King’s College London, London, UK;Department of Pulmonary Medicine, AOU S. Luigi Gonzaga, Orbassano, Turin, Italy;Department of Surgical Sciences, University of Turin, Turin, Italy;Department of Surgical Sciences, University of Turin, Turin, Italy;Department of Anaesthesia, Intensive Care and Emergency, Città della Salute e della Scienza University Hospital, Turin, Italy;University of Turin, Turin, Italy;

关键词: COVID-19;    Respiratory failure;    Helmet-CPAP;    Non-rebreather mask;    Venturi mask;    Respiratory effort;    Lung stress;    Gas-exchange;    Hemodynamics;   

DOI  :  10.1186/s13613-023-01202-0

 received in 2023-08-17, accepted in 2023-10-06,  发布年份 2023

来源: Springer

【 摘 要 】

Backgroundin COVID-19 acute respiratory failure, the effects of CPAP and FiO2 on respiratory effort and lung stress are unclear. We hypothesize that, in the compliant lungs of early Sars-CoV-2 pneumonia, the application of positive pressure through Helmet-CPAP may not decrease respiratory effort, and rather worsen lung stress and oxygenation when compared to higher FiO2 delivered via oxygen masks.MethodsIn this single-center (S.Luigi Gonzaga University-Hospital, Turin, Italy), randomized, crossover study, we included patients receiving Helmet-CPAP for early (< 48 h) COVID-19 pneumonia without additional cardiac or respiratory disease. Healthy subjects were included as controls. Participants were equipped with an esophageal catheter, a non-invasive cardiac output monitor, and an arterial catheter. The protocol consisted of a random sequence of non-rebreather mask (NRB), Helmet-CPAP (with variable positive pressure and FiO2) and Venturi mask (FiO2 0.5), each delivered for 20 min. Study outcomes were changes in respiratory effort (esophageal swing), total lung stress (dynamic + static transpulmonary pressure), gas-exchange and hemodynamics.ResultsWe enrolled 28 COVID-19 patients and 7 healthy controls. In all patients, respiratory effort increased from NRB to Helmet-CPAP (5.0 ± 3.7 vs 8.3 ± 3.9 cmH2O, p < 0.01). However, Helmet’s pressure decreased by a comparable amount during inspiration (− 3.1 ± 1.0 cmH2O, p = 0.16), therefore dynamic stress remained stable (p = 0.97). Changes in static and total lung stress from NRB to Helmet-CPAP were overall not significant (p = 0.07 and p = 0.09, respectively), but showed high interpatient variability, ranging from − 4.5 to + 6.1 cmH2O, and from − 5.8 to + 5.7 cmH2O, respectively. All findings were confirmed in healthy subjects, except for an increase in dynamic stress (p < 0.01). PaO2 decreased from NRB to Helmet-CPAP with FiO2 0.5 (107 ± 55 vs 86 ± 30 mmHg, p < 0.01), irrespective of positive pressure levels (p = 0.64). Conversely, with Helmet’s FiO2 0.9, PaO2 increased (p < 0.01), but oxygen delivery remained stable (p = 0.48) as cardiac output decreased (p = 0.02). When PaO2 fell below 60 mmHg with VM, respiratory effort increased proportionally (p < 0.01, r = 0.81).ConclusionsIn early COVID-19 pneumonia, Helmet-CPAP increases respiratory effort without altering dynamic stress, while the effects upon static and total stress are variable, requiring individual assessment. Oxygen masks with higher FiO2 provide better oxygenation with lower respiratory effort.Trial registration Retrospectively registered (13-May-2021): clinicaltrials.gov (NCT04885517), https://clinicaltrials.gov/ct2/show/NCT04885517.

【 授权许可】

CC BY   
© La Société de Réanimation de Langue Francaise = The French Society of Intensive Care (SRLF) 2023

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