Pope Francis’s health worsened significantly Friday afternoon as his respiratory condition was irritated and necessitated the return of mechanical ventilation. Earlier in the day, the pontiff “experienced an isolated episode of bronchospasm,

According to a Feb. 28 medical bulletin from the Holy See, after a morning spent in prayer, receiving the Eucharist, and doing respiratory physiotherapy, Pope Francis experienced in the early afternoon “an isolated crisis of bronchospasm” — a tightening of the muscles that line the airways in the lungs, causing wheezing and coughing.

The Vatican said Francis, 88, who has been hospitalized for pneumonia, was responding well to treatment and that it was too soon to say how serious the incident was.