Pope Francis rested overnight in the hospital, the Vatican said earlier Sunday, adding that his night "passed peacefully."

The Vatican said Francis hadn't had any more respiratory crises since Saturday night but was still receiving high flows of supplemental oxygen. Some blood tests showed "initial, mild, kidney failure," but doctors said it was under control.

Pope Francis remained in critical condition Sunday and blood tests show early kidney failure but he remains alert and “well-oriented,” and attended Mass, the Vatican said, as the 88-year-old pontiff battles pneumonia and a complex lung infection.