ROME — Pope Francis was in stable condition Tuesday and breathing with just the help of supplemental oxygen after respiratory crises a day earlier, but will resume using a ventilation mask at night, the Vatican said.

In its late update, the Vatican said Francis had no further respiratory episodes during a day spent praying, resting and undergoing respiratory physiotherapy to try to help him fight double pneumonia.

The 88-year-old pope, who has chronic lung disease and had part of one lung removed as a young man, had two respiratory crises on Monday in a setback to his recovery.

Doctors extracted “copious” amounts of mucus from his lungs. They put him on a noninvasive mechanical ventilation mask to help him breathe and he slept with it through the night, but was stable enough on Tuesday morning to use just high flows of supplemental oxygen delivered by a nasal tube.

Doctors planned to resume using the mask while he sleeps Tuesday night, so that oxygen is pumped into his lungs via a mask that covers his nose and mouth.

Doctors said his clinical condition was stable and that his prognosis remained guarded, meaning he is not out of danger.

Francis’ medical team has not provided an in-person update on his condition since Feb. 21, a sign of the up-and-down nature of his hospitalization, which began on Feb. 14 and is the longest of his 12-year papacy.

Argentines pray

On Tuesday, a group of Argentines from the country’s embassies in Rome brought a statue of Our Lady of Lujan to the Gemelli hospital to pray for Francis. The Argentine pope is particularly devoted to the blue veiled Lujan Madonna, which has been revered in Argentina since the 17th century. “I am very happy to be now close to him,” said the Rev. Fernando Laguna, parish priest of the Argentine church in Rome. “I would like to hug him, but it’s not possible, but he told us that a prayer is like a hug So I am happy despite the pain.”

Preparing for Lent

Francis’ treatment comes as the Vatican prepares for Lent, the solemn period leading up to Easter on April 20. As it is, a cardinal has been designated to take Francis’ place this week on Ash Wednesday, which opens Lent with a traditional service and procession in Rome. The pope was also supposed to attend a spiritual retreat this coming weekend with the rest of the Holy See hierarchy.

On Tuesday, the Vatican said the retreat would go ahead without Francis but in “spiritual communion” with him. The theme, selected weeks ago and well before Francis got sick, was “Hope in eternal life.”

Francis, who is not physically active, uses a wheelchair and is overweight, had been undergoing respiratory physiotherapy to try to improve his lung function. The accumulation of secretions in his lungs was a sign that he doesn’t have the muscle tone to cough vigorously enough to expel the fluid.