Francesco Corradi1,2, Alessandro Isirdi3,4, Paolo Malacarne5, Gregorio Santori6, Greta Barbieri7, Chiara Romei5, Tiziana Bove8, Luigi Vetrugno8, Marco Falcone7, Pietro Bertini5, Fabio Guarracino5, Giovanni Landoni9,10, Francesco Forfori3,4. 1. Department of Surgical, Medical, Molecular Pathology and Critical Care Medicine, University of Pisa, Pisa, Italy - francesco.corradi@unipi.it. 2. E.O. Ospedali Galliera, Genoa, Italy - francesco.corradi@unipi.it. 3. Department of Surgical, Medical, Molecular Pathology and Critical Care Medicine, University of Pisa, Pisa, Italy. 4. E.O. Ospedali Galliera, Genoa, Italy. 5. University Hospital of Pisa, Pisa, Italy. 6. Department of Surgical Sciences and Integrated Diagnostics, University of Genoa, Genoa, Italy. 7. Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy. 8. Anesthesiology and Intensive Care Clinic, Department of Medicine, University of Udine, Udine, Italy. 9. Department of Anesthesiology and Intensive Care, IRCCS San Raffaele Scientific Institute, Milan, Italy. 10. School of Medicine, Vita-Salute San Raffaele University, Milan, Italy.
Abstract
BACKGROUND: The aim of this study was to evaluate whether measurement of diaphragm thickness (DT) by ultrasonography may be a clinically useful noninvasive method for identifying patients at risk of adverse outcomes defined as need of invasive mechanical ventilation or death. METHODS: We prospectively enrolled 77 patients with laboratory-confirmed COVID-19 infection admitted to our intermediate care unit in Pisa between March 5 and March 30, 2020, with follow-up until hospital discharge or death. Logistic regression was used identify variables potentially associated with adverse outcomes and those P<0.10 were entered into a multivariate logistic regression model. Cumulative probability for lack of adverse outcomes in patients with or without low baseline diaphragm muscle mass was calculated with the Kaplan-Meier product-limit estimator. RESULTS: The main findings of this study are that: 1) patients who developed adverse outcomes had thinner diaphragm than those who did not (2.0 vs. 2.2 mm, P=0.001); and 2) DT and lymphocyte count were independent significant predictors of adverse outcomes, with end-expiratory DT being the strongest (ß=-708; OR=0.492; P=0.018). CONCLUSIONS: Diaphragmatic ultrasound may be a valid tool to evaluate the risk of respiratory failure. Evaluating the need of mechanical ventilation treatment should be based not only on PaO<inf>2</inf>/FiO<inf>2</inf>, but on a more comprehensive assessment including DT because if the lungs become less compliant a thinner diaphragm, albeit free of intrinsic abnormality, may become exhausted, thus contributing to severe respiratory failure.
BACKGROUND: The aim of this study was to evaluate whether measurement of diaphragm thickness (DT) by ultrasonography may be a clinically useful noninvasive method for identifying patients at risk of adverse outcomes defined as need of invasive mechanical ventilation or death. METHODS: We prospectively enrolled 77 patients with laboratory-confirmed COVID-19infection admitted to our intermediate care unit in Pisa between March 5 and March 30, 2020, with follow-up until hospital discharge or death. Logistic regression was used identify variables potentially associated with adverse outcomes and those P<0.10 were entered into a multivariate logistic regression model. Cumulative probability for lack of adverse outcomes in patients with or without low baseline diaphragm muscle mass was calculated with the Kaplan-Meier product-limit estimator. RESULTS: The main findings of this study are that: 1) patients who developed adverse outcomes had thinner diaphragm than those who did not (2.0 vs. 2.2 mm, P=0.001); and 2) DT and lymphocyte count were independent significant predictors of adverse outcomes, with end-expiratory DT being the strongest (ß=-708; OR=0.492; P=0.018). CONCLUSIONS: Diaphragmatic ultrasound may be a valid tool to evaluate the risk of respiratory failure. Evaluating the need of mechanical ventilation treatment should be based not only on PaO<inf>2</inf>/FiO<inf>2</inf>, but on a more comprehensive assessment including DT because if the lungs become less compliant a thinner diaphragm, albeit free of intrinsic abnormality, may become exhausted, thus contributing to severe respiratory failure.
Authors: David M Maslove; Stephanie Sibley; J Gordon Boyd; Ewan C Goligher; Laveena Munshi; Isaac I Bogoch; Bram Rochwerg Journal: Chest Date: 2021-10-13 Impact factor: 10.262