The Pope has had two episodes of “acute respiratory failure”, the Vatican has said.
The 88-year-old has been in hospital since 14 February with a severe respiratory infection that triggered other complications.
The Vatican said the respiratory failures were caused by “significant accumulation” of mucus in his lungs and a “bronchospasm”, akin to an asthma attack.
Doctors were then required to perform two bronchoscopies – a test which sees medics use a long, thin, telescope with a light to look into the lungs – to evaluate the Pope’s air passages, the statement said.
“In the afternoon, non-invasive mechanical ventilation was resumed,” The Vatican continued. “The Holy Father has always remained vigilant, oriented and collaborative. The prognosis remains reserved.”
Vatican sources said the situation had been calm this morning, before becoming worse this afternoon.
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The respiratory issues Francis suffered today are due to an ongoing infection rather than a new one but he is not out of danger, they added.
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Pope’s condition is slightly improved but remains complex, Vatican sources say
Asked if the Pope is in good spirits, they gave no answer. When asked if the Vatican’s apartment is getting ready to welcome Francis back, the source said it was too premature to discuss this.
His clinical picture remains complex, they said.
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Earlier on Monday, Francis issued a written message after Vatican officials begged him to let his voice be heard following more than two weeks out of public view.
He thanked his doctors for their care and well-wishers for their prayers, before praying for peace in Ukraine and elsewhere.
“From here, war appears even more absurd,” he wrote.
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This has become the longest public absence of his 12-year papacy.
Cardinal Konrad Krajewski presided over the evening rosary prayer in St Peter’s Square on Sunday night.
“Let us pray together with the entire church for the health of the Holy Father Francis,” he said.
