The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an emerging infectious disease with high transmissibility. Around 20-25% of infected individuals develop severe COVID-19 disease requiring hospitalization and 5-8% require intubation secondary to viral pneumonia and acute respiratory distress syndrome (ARDS). Distinct features of COVID-19 ARDS were found since Nov 2019, including relatively normal lung mechanics, activation of the RAAS system, selective injury of type II alveolar cells, and presence of vasodilation vessel and micro-thrombosis. The mechanism, potential useful biomarker, and the optimal ventilation strategies for COVID-19 ARDS need to be systematically studied. This study hypothesized that the low-tidal volume ventilation strategy is effective in COVID-19 ARDS. We will retrospectively review the clinical presentation, epidemiologic data, laboratory and image examination, medication use, lung mechanics、serum biomarker, long-term pulmonary function test, and clinical outcomes in COVID-19 ARDS, influenza ARDS, and SARS ARDS patients. We will also prospectively monitor the lung function of COVID ARDS patients using personal pulmonary function devices after discharge from NTUH. The overall purpose of this study is to investigate the prognostic indicators of COVID ARDS patients and their long-term pulmonary function follow-up.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an emerging infectious disease with high transmissibility. Around 20-25% of infected individuals develop severe COVID-19 disease requiring hospitalization and 5-8% require intubation secondary to viral pneumonia and acute respiratory distress syndrome (ARDS). Distinct features of COVID-19 ARDS were found since Nov 2019, including relatively normal lung mechanics, activation of the RAAS system, selective injury of type II alveolar cells, and presence of vasodilation vessel and micro-thrombosis. The mechanism, potential useful biomarker, and the optimal ventilation strategies for COVID-19 ARDS need to be systematically studied. This study hypothesized that the low-tidal volume ventilation strategy is effective in COVID-19 ARDS. We will retrospectively review the clinical presentation, epidemiologic data, laboratory and image examination, medication use, lung mechanics、serum biomarker, long-term pulmonary function test, and clinical outcomes in COVID-19 ARDS, influenza ARDS, and SARS ARDS patients. We will also prospectively monitor the lung function of COVID ARDS patients using personal pulmonary function devices after discharge from NTUH. The overall purpose of this study is to investigate the prognostic indicators of COVID ARDS patients and their long-term pulmonary function follow-up.The SARS-CoV-2 (COVID-19) ARDS is an emerging novel devastating disease with high mortality. Distinct features were found since Nov 2019, including relatively normal lung mechanics, activation of the RAAS system, selective injury of type II alveolar cells, and presence of vasodilation vessel and micro-thrombosis. The optimal ventilation strategies for COVID-19 ARDS need to be systematically studied. The overall purpose of this study is to investigate the prognostic indicators in COVID-19 ARDS patients.Specific Aim 1: To develop a REDcap database of clinical and biologic information in subjects with COVID-19, and to investigate the prognostic indicators compared with influenza and SARS ARDS patients.Specific Aim 2: To follow up the long-term change pulmonary function test of COVID ARDS patients using home-based personal pulmonary function test device

Inclusion Criteria:

1. Adult >20 years old
2. Retrospective cohort by medical chart review：COVID-19 patients, Influenza patients, and SARS patients at NTUH
3. Prospective cohort：COVID-19 confirmed patients intubated and receiving mechanical ventilation > 24 hours at NTUH, got extubated and discharged

Exclusion Criteria:

1. Pregnancy
2. No consent/inability to obtain consent or appropriate legal representative not available

Experimental Group：COVID-19 case

Control Group：Healthy population without COVID-19