Associated Press Writer
VATICAN CITY - Pope John Paul II's doctors were on guard for complications Wednesday, a day after the frail, 84-year-old pontiff was hospitalized with the flu and breathing trouble.
Pneumonia remained a potentially deadly threat, but the Holy See insisted there was "no cause for alarm." Roman Catholics from Poland to the Philippines prayed for his recovery.
The pope will be hospitalized for a few more days to afford "many means to stay ready for any complications," said Cardinal Javier Lozano Barragan, head of the Vatican's health care office.
The slumping pontiff also suffers from Parkinson's disease and crippling hip and knee ailments, and his inability to hold his back up straight has left his lungs and diaphragm in a crushed position, Barragan told Associated Press Television News.
Tests showed the pope's heart and respiration were normal, and he felt well enough to participate from his bed in a Mass celebrated by his secretary, said papal spokesman Joaquin Navarro-Valls.
He said John Paul was running a slight fever and would spend "a few more days" for treatment of respiratory problems at Rome's Gemelli Polyclinic, where he was taken by ambulance Tuesday night.
"There is no cause for alarm," Navarro-Valls said.
Cardinal Angelo Sodano, the Vatican secretary of state, also played down the severity of the illness Wednesday evening.
The pope was "recovering well," Sodano told private Italian TV Canale 5, adding that he expected the situation to improve in a few days.
Still, American experts said a case like the pontiff's could lead to life-threatening pneumonia. "That's the complication of influenza that most frequently, by far, carries people off," said Dr. William Schaffner, an infectious diseases expert at Vanderbilt University.
"I'm sure every physician (following news reports of the pope's case) is already worried that pneumonia might develop," Schaffner said.
Elderly men with long-standing, debilitating chronic disease like Parkinson's often die of pneumonia, which comes as "the final straw" in a long assault by disease on the body, said geriatrics specialist Dr. William Hall of the University of Rochester.
The pope's slumped posture would not only impede his breathing but also make it harder for him to cough normally, a reaction that in healthy people helps keep pneumonia bacteria from entering the lungs, Hall said.
Pneumonia is "often very difficult to treat because you have introduced bacteria that don't belong in the lungs," said Dr. Michael Freedman, head of geriatrics at New York University Medical Center.
"You usually need multiple antibiotics programs," he said. "The big danger is that if you are having trouble getting air into you, you can just tire out and you just can't keep up with it."
In St. Peter's Square, in John Paul's native Poland and in many of the 129 countries the pope has visited over a 26-year papacy, the faithful paused to pray for the spiritual leader of the world's 1 billion Catholics.
White House press secretary Scott McClellan said Americans' "thoughts and prayers are with the Holy Father," and in Rome, chief rabbi Riccarco Di Segni offered prayers for a quick recovery.
Navarro-Valls insisted that John Paul did not lose consciousness or require the insertion of a tube into his windpipe to help him breathe - a procedure known as a tracheotomy - and he characterized the hospitalization as "mainly precautionary."