Residual respiratory impairment after COVID-19 pneumonia.

INTRODUCTION: The novel coronavirus SARS-Cov-2 can infect the respiratory tract causing a spectrum of disease varying from mild to fatal pneumonia, and known as COVID-19. Ongoing clinical research is assessing the potential for long-term respiratory sequelae in these patients. We assessed the respiratory function in a cohort of patients after recovering from SARS-Cov-2 infection, stratified according to PaO2/FiO2 (p/F) values. METHOD: Approximately one month after hospital discharge, 86 COVID-19 patients underwent physical examination, arterial blood gas (ABG) analysis, pulmonary function tests (PFTs), and six-minute walk test (6MWT). Patients were also asked to quantify the severity of dyspnoea and cough before, during, and after hospitalization using a visual analogic scale (VAS). Seventy-six subjects with ABG during hospitalization were stratified in three groups according to their worst p/F values: above 300 (n = 38), between 200 and 300 (n = 30) and below 200 (n = 20). RESULTS: On PFTs, lung volumes were overall preserved yet, mean percent predicted residual volume was slightly reduced (74.8 ± 18.1%). Percent predicted diffusing capacity for carbon monoxide (DLCO) was also mildly reduced (77.2 ± 16.5%). Patients reported residual breathlessness at the time of the visit (VAS 19.8, p < 0.001). Patients with p/F below 200 during hospitalization had lower percent predicted forced vital capacity (p = 0.005), lower percent predicted total lung capacity (p = 0.012), lower DLCO (p < 0.001) and shorter 6MWT distance (p = 0.004) than patients with higher p/F. CONCLUSION: Approximately one month after hospital discharge, patients with COVID-19 can have residual respiratory impairment, including lower exercise tolerance. The extent of this impairment seems to correlate with the severity of respiratory failure during hospitalization.

Ventilatory Support in Patients with COVID-19.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused the novel coronavirus disease 2019 (COVID-19) pandemic, which spread throughout the world. Acute hypoxemic respiratory failure is the most dangerous complication of COVID-19 pneumonia. To date, no specific therapeutic drugs or vaccines have been proven efficacious. Ventilatory support is still a significant challenge for physicians facing COVID-19. The mechanisms underlying hypoxemia in those patients are not fully understood, but a new physiopathology model has been proposed. Oxygen therapy should be delivered to patients with mild to moderate hypoxemia. More severe patients could benefit from other treatments (high-flow nasal cannula, noninvasive ventilation or intubation, and invasive ventilation). Given the rapid evolution of COVID-19, there has been a paucity of the high-quality data that typically inform clinical practice guidelines from professional societies, and a worldwide consensus is still lacking. This chapter aims to illustrate the potentials of ventilatory support as therapeutic options for adult and pediatric patients affected by COVID-19 pneumonia.