Pope Francis had a peaceful night and is resting, the Vatican said on Saturday.
The pontiff has been in hospital for just over two weeks – since 14 February – fighting double pneumonia.
After days of cautious optimism, the 88-year-old pontiff suffered a setback on Friday, experiencing an “isolated breathing crisis” that required non-invasive, mechanical ventilation, the Vatican said.
The pope, it said, also had “an episode of vomiting with inhalation.” He needed aspiration to help remove the vomit from his airways, the Vatican added.
The episode, which occurred in the early afternoon, resulted in a “sudden worsening of the respiratory picture”. Doctors decided to keep his prognosis guarded.
Earlier on Friday, Francis had spent the morning alternating high flows of supplemental oxygen with a mask and praying in the chapel. He had had breakfast, read the day’s newspapers and was receiving respiratory physiotherapy, the Vatican said.
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His doctors are expected to take 24 to 48 hours to evaluate how the episode will impact the state of his clinical condition.
“The night passed peacefully, the pope is resting,” the Vatican said on Saturday, giving no further details. The next medical bulletin is expected around 7pm Rome time (1800 GMT).
The Vatican has already made alternative plans for Ash Wednesday next week, making clear Francis still had a long road ahead. Cardinal Angelo De Donatis, a Vatican official and former vicar of Rome, will preside over the 5 March ceremony and procession that inaugurates the church’s solemn Lenten season leading up to Easter in April.
Francis was admitted to Rome’s Gemelli hospital on 14 February with a severe respiratory infection that degenerated into double pneumonia – a serious infection of both lungs that can inflame and scar them, making it difficult to breathe.
Francis has suffered several bouts of ill health over the past two years and is especially prone to lung infections because he developed pleurisy as a young adult and had part of one lung removed.