학술논문
Computed tomography assessment of PEEP-induced alveolar recruitment in patients with severe COVID-19 pneumonia
positive end-expiratory pressure
positive end-expiratory pressure
Document Type
Clinical report
Author
Ball, Lorenzo; Robba, Chiara; Maiello, Lorenzo; Herrmann, Jacob; Gerard, Sarah E.; Xin, Yi; Battaglini, Denise; Brunetti, Iole; Minetti, Giuseppe; Seitun, Sara; Vena, Antonio; Giacobbe, Daniele Roberto; Bassetti, Matteo; Rocco, Patricia R. M.; Cereda, Maurizio; Castellan, Lucio; Patroniti, Nicolò; Pelosi, Paolo; Gratarola, Angelo; Loconte, Maurizio; Molin, Alexandre; Orefice, Giulia; Iannuzzi, Francesca; Costantino, Federico; Battioni, Dario; Bovio, Giulio; Buconte, Gerolama; Casaleggio, Alessandro; Cittadini, Giuseppe; Dogliotti, Luca; Giasotto, Veronica; Pigati, Maria; Santacroce, Elena; Zaottini, Federico; Dentone, Chiara; Taramasso, Lucia; Magnasco, Laura; Valbusa, Alberto; Bastianello, Matilde
Source
Critical Care. February 24, 2021, Vol. 25 Issue 1
Subject
Language
English
ISSN
1364-8535
Abstract
Author(s): Lorenzo Ball[sup.1,2] , Chiara Robba[sup.2] , Lorenzo Maiello[sup.1] , Jacob Herrmann[sup.3] , Sarah E. Gerard[sup.4] , Yi Xin[sup.5] , Denise Battaglini[sup.2] , Iole Brunetti[sup.2] , Giuseppe Minetti[sup.6] , Sara [...]
Background There is a paucity of data concerning the optimal ventilator management in patients with COVID-19 pneumonia; particularly, the optimal levels of positive-end expiratory pressure (PEEP) are unknown. We aimed to investigate the effects of two levels of PEEP on alveolar recruitment in critically ill patients with severe COVID-19 pneumonia. Methods A single-center cohort study was conducted in a 39-bed intensive care unit at a university-affiliated hospital in Genoa, Italy. Chest computed tomography (CT) was performed to quantify aeration at 8 and 16 cmH.sub.2O PEEP. The primary endpoint was the amount of alveolar recruitment, defined as the change in the non-aerated compartment at the two PEEP levels on CT scan. Results Forty-two patients were included in this analysis. Alveolar recruitment was median [interquartile range] 2.7 [0.7-4.5] % of lung weight and was not associated with excess lung weight, PaO.sub.2/FiO.sub.2 ratio, respiratory system compliance, inflammatory and thrombophilia markers. Patients in the upper quartile of recruitment (recruiters), compared to non-recruiters, had comparable clinical characteristics, lung weight and gas volume. Alveolar recruitment was not different in patients with lower versus higher respiratory system compliance. In a subgroup of 20 patients with available gas exchange data, increasing PEEP decreased respiratory system compliance (median difference, MD - 9 ml/cmH.sub.2O, 95% CI from - 12 to - 6 ml/cmH.sub.2O, p < 0.001) and the ventilatory ratio (MD - 0.1, 95% CI from - 0.3 to - 0.1, p = 0.003), increased PaO.sub.2 with FiO.sub.2 = 0.5 (MD 24 mmHg, 95% CI from 12 to 51 mmHg, p < 0.001), but did not change PaO.sub.2 with FiO.sub.2 = 1.0 (MD 7 mmHg, 95% CI from - 12 to 49 mmHg, p = 0.313). Moreover, alveolar recruitment was not correlated with improvement of oxygenation or venous admixture. Conclusions In patients with severe COVID-19 pneumonia, higher PEEP resulted in limited alveolar recruitment. These findings suggest limiting PEEP strictly to the values necessary to maintain oxygenation, thus avoiding the use of higher PEEP levels. Keywords: COVID-19, ARDS, Respiratory system mechanics, Mechanical ventilation, CT scan
Background There is a paucity of data concerning the optimal ventilator management in patients with COVID-19 pneumonia; particularly, the optimal levels of positive-end expiratory pressure (PEEP) are unknown. We aimed to investigate the effects of two levels of PEEP on alveolar recruitment in critically ill patients with severe COVID-19 pneumonia. Methods A single-center cohort study was conducted in a 39-bed intensive care unit at a university-affiliated hospital in Genoa, Italy. Chest computed tomography (CT) was performed to quantify aeration at 8 and 16 cmH.sub.2O PEEP. The primary endpoint was the amount of alveolar recruitment, defined as the change in the non-aerated compartment at the two PEEP levels on CT scan. Results Forty-two patients were included in this analysis. Alveolar recruitment was median [interquartile range] 2.7 [0.7-4.5] % of lung weight and was not associated with excess lung weight, PaO.sub.2/FiO.sub.2 ratio, respiratory system compliance, inflammatory and thrombophilia markers. Patients in the upper quartile of recruitment (recruiters), compared to non-recruiters, had comparable clinical characteristics, lung weight and gas volume. Alveolar recruitment was not different in patients with lower versus higher respiratory system compliance. In a subgroup of 20 patients with available gas exchange data, increasing PEEP decreased respiratory system compliance (median difference, MD - 9 ml/cmH.sub.2O, 95% CI from - 12 to - 6 ml/cmH.sub.2O, p < 0.001) and the ventilatory ratio (MD - 0.1, 95% CI from - 0.3 to - 0.1, p = 0.003), increased PaO.sub.2 with FiO.sub.2 = 0.5 (MD 24 mmHg, 95% CI from 12 to 51 mmHg, p < 0.001), but did not change PaO.sub.2 with FiO.sub.2 = 1.0 (MD 7 mmHg, 95% CI from - 12 to 49 mmHg, p = 0.313). Moreover, alveolar recruitment was not correlated with improvement of oxygenation or venous admixture. Conclusions In patients with severe COVID-19 pneumonia, higher PEEP resulted in limited alveolar recruitment. These findings suggest limiting PEEP strictly to the values necessary to maintain oxygenation, thus avoiding the use of higher PEEP levels. Keywords: COVID-19, ARDS, Respiratory system mechanics, Mechanical ventilation, CT scan