Hit by a Series of Organ Failures

Like many other elderly people with chronic illnesses, Pope John Paul II suffered a cascade of organ failures triggered by a simple bacterial infection.

Crippled by advanced Parkinson’s disease and still weakened from a recent bout of the flu, the 84-year-old pope was especially vulnerable to infection -- and later unable to fight its progression.

Each time doctors treated one problem, a new complication arose. A urinary tract infection became a blood infection, which attacked the kidneys and strained the heart and lungs.

“Once this multi-system organ failure starts happening, you really can’t come back,” said Dr. Benjamin Ansell, an internist at UCLA Medical Center.

Several medical experts who followed news reports of the pope’s decline said it appeared that he had opted for a relatively comfortable death rather than aggressive treatment that might have briefly extended his life.

While a feeding tube was inserted through his nose, he remained at his Vatican apartment, where it would be difficult to provide dialysis to take over for his failing kidneys or place him on a ventilator to aid his breathing.

“At some point he -- or somebody who knew his directive -- said, ‘We are going to go this far and no further,’ ” said Dr. Leslie Saxon, a cardiologist at USC’s Keck School of Medicine.

Over the last decade, the pope slowly deteriorated from Parkinson’s, an incurable illness that destroys brain cells that produce the chemical dopamine.

The disease’s effects include memory and cognitive impairment, trembling hands, gradual loss of muscle control and a stooped posture that compresses the lungs, making breathing difficult.

Parkinson’s patients “can’t expand their chests as well” as the healthy can, said Dr. Jeff Bronstein, a neurologist at UCLA Medical Center. “It interferes with their ability to clear their lungs. It is harder to get over the infections.”

In February, after the pope was diagnosed with the flu, doctors performed a tracheostomy, inserting a tube through a hole in his throat to help him breathe and make it easier to suction out saliva and debris that can enter the lungs and cause pneumonia.

The tube carries its own risk, because it can make swallowing harder and decrease appetite. With less nutrition, a patient is more vulnerable to infection.

The pope’s rapid decline this week began with a urinary tract infection -- an ailment common among older men, who often have difficulty completely emptying their bladder.

Such infections are usually treatable with antibiotics. But with poor nourishment, weak lungs and muscles incapacitated by Parkinson’s, the pope could not stop its advance.

He developed a high fever. The bacterial infection spread to his blood, leading to a condition known as septic shock.

As the body struggles against the infection in such situations, the normally elastic blood vessels relax, leaking fluid into the surrounding tissue and organs.

Blood pressure begins to drop dangerously. To compensate, the heart must work harder to supply organs with blood.

Doctors can pump fluid into the circulatory system to maintain blood pressure -- a short-term fix that can further strain the heart.

The lungs must work harder to provide oxygen to the blood-starved body.

Fluid can leak into the lungs, making it even harder to breathe.

Some patients can develop a suffocating feeling known as “air hunger,” Ansell said.

Breathing difficulties can be treated with morphine to ease the pain, although the drug also depresses the respiratory system and can speed death.

The Vatican did not say whether the pope had received morphine.

The lack of blood and oxygen can eventually make patients lose consciousness.

In the meantime, the kidneys, deprived of blood, begin to shut down, leading to an accumulation of the toxins they normally clear from the body.

Those can cause the heart to spasm or stop.

“For most patients, it is renal [kidney] failure that is the end event,” said Dr. Lee Goldberg, a cardiologist at the University of Pennsylvania.

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Final complications

Pope John Paul II suffered multi-organ failure as a result of a string of problems complicated by advanced Parkinson’s disease.

Parkinson’s disease

This degenerative nerve disease impairs movement and can make breathing difficult.

Septic shock

A result of infection spreading to the bloodstream, it is characterized by failure of the circulatory system and severe multi-organ problems.

Overworked heart

Stress builds as pumping is speeded up to supply oxygen to the bloodstream as blood pressure drops from septic shock.

Urinary tract infection

A common problem in people who cannot fully empty their bladder, allowing bacteria to build up.

Impaired lungs

Parkinson’s disease typically makes it hard for patients to clear congestion from their lungs.

Weakened kidneys

Lack of oxygen can cause kidneys to stop filtering toxins from the bloodstream.

Sources: Times research, National Parkinson’s Foundation, www.merck.com