Doctors have removed a mechanical ventilator from Pope Francis as the pontiff continues to recover from a respiratory infection that put him in the hospital in critical condition, the Vatican announced Sunday.

Pope Francis, in hospital for double pneumonia, is improving slightly, has no fever, and his blood analyses are stable, the Vatican said on Thursday.

Pope Francis suffered two episodes of acute respiratory failure Monday, the Vatican said, a fresh setback in the worst health crisis of his papacy.

The 88-year-old, who had part of one lung removed as a young man, experienced two acute respiratory crises on Monday.

Pope Francis suffered two new episodes of acute respiratory crises Monday and was put back on noninvasive mechanical ventilation, the Vatican said. Francis had inhaled “copious” amounts of mucus in another setback in what has become a more than two-week battle to overcome a complex respiratory infection and pneumonia.