ROME – Despite several days of slight improvement in his overall clinical status, Pope Francis Friday suffered what doctors described as a bronchial spasm that led to a worsening of his respiratory condition.

In a Feb. 28 medical bulletin, the Vatican said that after spending the morning alternating between respiratory physiotherapy and prayer in the chapel next to his suite on the 10th floor of Rome’s Gemelli Hospital, the pope suffered “a bronchospasm.”

This condition in medical jargon is when the muscles lining the bronchi, the tubes that connect your windpipe to your lungs, constrict and narrow, limiting the amount of oxygen the body receives.

As a result of the spasm, the Vatican said the pope experienced “an episode of vomiting with inhalation and a sudden worsening of the respiratory condition.”

According to doctors consulted by Crux, the episode meant that the pope inhaled gastric contents, saliva, food, or a combination, into his respiratory tract.

Doctors immediately “bronchoaspirated,” meaning they suctioned the contents he inhaled out of his respiratory tract, and they began use of NIV, or non-invasive ventilation, which doctors told Crux is a step between the regular oxygen mask, and a full mechanical ventilator in which the patient is intubated.

Friday’s statement said Francis had a “good response” to the NIV treatment, which consists of tightly sealing the oxygen mask to the nose and mouth so there is no passage of air, inducing pressure that is helpful for inhalation, when the patient is too weak to inhale properly on their own.

The Vatican said Pope Francis “remained alert and oriented at all times,” and cooperated with his treatment.

Given this latest crisis, doctors said the pope’s overall prognosis remains “guarded.”

Doctors consulted by Crux said the spasm with ingestion of the gastric contents into the pope’s respiratory system was serious and could put him at risk of developing another form of pneumonia called “ab ingestis pneumonia,” as it is usually impossible to suction everything out, and microbes could potentially infiltrate the respiratory tract in the food that was ingested.

Over the next few days, doctors told Crux, it will be important to monitor whether the pope’s fever returns, as this could be an indication that he has developed ab ingestis pneumonia.

Without knowing the pope’s full clinical status, doctors told Crux it is still possible for Pope Francis to recover, but he is also at risk of multi-organ failure if his respiratory problems continue to worsen.

Francis’s respiratory crisis Friday comes after several days of slight improvement, but with doctors consistently warning that he was not yet out of danger, and that an overall prognosis was therefore still unclear.

The Vatican announced earlier Friday that, due to Pope Francis’s ongoing hospitalization, his Ash Wednesday Mass and procession inaugurating the Lenten season will be led by Cardinal Angelo De Donatis, Major Penitentiary of the Vatican’s Apostolic Penitentiary.

He will lead a procession from the church of Sant’Anselmo all’Aventino to the Basilica of Santa Sabina together with various cardinals, archbishops, bishops, Benedictine fathers of Sant’Anselmo and the Dominican fathers of Santa Sabina, as well as members of the faithful.

At the end of the procession, he will celebrate Mass inside Santa Sabina with the imposition of the ashes.

The pope’s Saturday jubilee general audience has been canceled due to his hospital stay, though no word has yet been given about his Sunday Angelus address, which for the past two weeks he has not given, due to doctors’ orders to rest, choosing to publish his prepared text instead.

Masses, rosaries and other prayers have been offered for the pope throughout his hospital stay.

On Friday night, Argentine Cardinal Víctor Manuel Fernández, a close papal confidant and head of the Vatican’s Dicastery for the Doctrine of the Faith, is set to lead a rosary for the pope and his health in St. Peter’s Square.

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