Spontaneous Evolution of COVID-19 Lung Sequelae: Results from a Double-Step Follow-Up.

Background: Few studies have reported a double-step follow-up of patients after hospitalization for COVID-19.

Objectives: We designed an observational double-step follow-up study with a clinical, functional, and radiological evaluation at 2 and 6 months after COVID-19. The primary outcome was to describe symptoms, spirometry, and 6-minute walking test (6MWT) at 2 and 6 months.

Standardizing PaO2 for PaCO2 in P/F ratio predicts in-hospital mortality in acute respiratory failure due to Covid-19: A pilot prospective study.

Introduction: Up to fifteen percent of patients with novel pandemic coronavirus disease (Covid-19) have acute respiratory failure (ARF). Ratio between arterial partial pressure of oxygen (PaO2) and fraction of inspired oxygen (FiO2), P/F, is currently used as a marker of ARF severity in Covid-19. P/F does not reflect the respiratory efforts made by patients to maintain arterial blood oxygenation, such as tachypnea and hyperpnea, leading to hypocapnia.