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Pope had 'tranquil' night after respiratory crisis,

Vatican says

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Francis, 88, has double pneumonia, in critical condition

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Doctors said on Saturday that prognosis is 'guarded'

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Pope has been in hospital since February 14

(Adds comments from pilgrims in paragraphs 9-13)

By Joshua McElwee

VATICAN CITY, Feb 23 (Reuters) -

Pope Francis, in critical condition battling double

pneumonia, had a "tranquil" night and rested following a

respiratory crisis and blood transfusions, the Vatican said on

Sunday.

The pope was admitted to Rome's Gemelli hospital on February

14 after experiencing difficulty breathing for several days and

subsequently had pneumonia diagnosed in both lungs.

The Vatican described his condition as critical for the

first time on Saturday, reporting that the 88-year-old Francis

had needed supplemental oxygen and blood transfusions that day

after a "prolonged asthma-like respiratory crisis".

"The night was tranquil, the pope rested," the Vatican said

in a one-sentence update on Sunday morning without providing

further information. A further update on the pope's condition is

expected later in the day.

Archbishop Rino Fisichella, a senior Vatican official, told

participants at a Mass in St. Peter's Basilica on Sunday morning

they should make their prayers for Francis "stronger and more

intense".

The Diocese of Rome, which the pope leads, announced a

special Mass for Sunday evening to pray for Francis, so that he

will have "the strength necessary to get through this moment of

trial".

Double pneumonia is a serious infection that can inflame and

scar both lungs, making it difficult to breathe. The Vatican has

described the pope's infection as "complex", saying it is being

caused by two or more microorganisms.

Francis, who has been pope since 2013, has suffered bouts of

ill health in the past two years. He is particularly prone to

lung infections because he developed pleurisy as a young adult

and had part of one lung removed.

PILGRIMS PRAY FOR POPE

Near the Vatican on Sunday morning, pilgrims were expressing

concern for the pope's condition.

"I am very, very sad," said Elvira Romana, from Italy. "I

don't know how you can continue on normally at this moment."

Matteo Licari, from Sardinia, said he was "extremely

worried". "Let's hope he can keep living," said Licari. "We are

waiting for him to come back here."

Outside Gemelli hospital, groups of people were gathering to

pray near a statue of the late Pope John Paul II, who was

treated at the facility many times during his long papacy.

People were leaving flowers and notes for Francis, and

lighting candles at the base of the late pope's memorial.

In a statement on Saturday evening, the Vatican said the

pope's respiratory crisis had required administration of

"high-flow oxygen".

It said he had also needed blood transfusions because tests

showed he had a low platelet count, which is associated with

anaemia. Platelets are cell fragments in our blood that form

clots and stop or prevent bleeding.

In a briefing on Friday, two of his doctors said the pope

was highly vulnerable because of his age and general frailty.

Dr. Sergio Alfieri, a senior member of the Gemelli staff,

said there was a risk the lung infection could spread to his

bloodstream and develop into sepsis, which "could be very

difficult to overcome".