Incidence, one-year progression and factors associated with respiratory muscle weakness after discharge from ICU for COVID-19

<bold>Background:</bold> After a stay in the intensive care unit for COVID-19, some patients have persistent symptoms and lung function abnormalities. Hypothesis: These defects may be related to inspiratory muscle weakness (IMW). <bold>Methods:</bold> Pulmonary function tests were performed at 3, 6 and 12 months after onset of symptoms, in patients admitted to ICU for COVID-19, and included exploration of respiratory muscles with maximal inspiratory pressure and sniff nasal inspiratory pressure measurement. The primary endpoint was incidence of IMW at 3 months. Secondary endpoints were factors associated with IMW and its evolution at 6 and 12 months. <bold>Results:</bold> 85 patients were included at 3 months. At 6 and 12 months, 80 and 73 completed the follow-up. Eighty-six percent received mechanical ventilation during ICU stay. The incidence of weakness was 21% at 3 months, 13% at 6 and 5% at 12 months. Older age, a hospital stay > 44 days, ICU stay > 17 days, use of neuromuscular blockers > 8 days, prone position sessions > 7 and duration of mechanical ventilation were factors associated with IMW. <fig><object-id>erj;64/suppl_68/PA5272/F1</object-id><object-id>F1</object-id><object-id>F1</object-id><graphic></graphic></fig> Figure 1. Changes in inspiratory muscle strength following severe SARS-CoV-2 infection <bold>Conclusion:</bold> IMW persisted in many patients after hospitalization in ICU, possibly explaining dyspnoea. It was associated with the duration of mechanical ventilation and the length of ICU stay. It improved at 6 and 12 months, as well as dyspnoea.