Patrick Bouvier Kennedy, born premature, died after 39 hours of life on Aug. 7, 1963, three months before his father, President John F. Kennedy, was assassinated in Dallas.
Though the baby was a healthy weight, he developed what was known then as hyaline membrane disease, a condition that killed about 25,000 children a year. At the time, the first family had Caroline, 5, and John Jr., 2, but Jacqueline Kennedy had previously had a miscarriage and a stillborn daughter.
The death of the presidential baby a half a century ago today was a critical event, according to historians, one that sparked medical advances that did for the survival of preemies what Sputnik did for the space race.
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That same year, a Canadian doctor had pioneered the controversial use of a ventilator and saved a similarly sick 34-week-old baby, but American doctors couldn't do the same for the Kennedy baby.
"The president was pretty embarrassed about that," said Dr. Jay Greenspan, chief of pediatrics at Thomas Jefferson Medical College and Nemours/A.I. duPont Hospital for Children, where today about 95 percent of all infants diagnosed with what is now known as respiratory distress syndrome survive.
"We have come a long way," said Greenspan. "It was so tragic that the family went though this -- and you wish you could have been there. It was a simple fix. … The baby was really just slightly premature. He would be sort of an afterthought now in the after-care nursery."
Today, respiratory distress syndrome, or RDS, affects more than 16,000 premature infants in the United States each year, according to the March of Dimes. Babies with the condition have immature lungs that lack the protein surfactant that keeps their small air sacs from collapsing.
But it was the presidential spotlight that would ultimately transform the field, giving birth to neonatology and the modern neonatal intensive care unit, or NICU.
The Kennedy baby's death put a new focus on diseases of the newborn and resulted in increased funding for research by the National Institutes of Health, according to Dr. Suhas M. Nafday, director of Newborn Services at the Children's Hospital at Montefiore Medical Center in New York.
"This event energized the neonatal researchers into action to look for an effective management of RDS," he said.
Millions of babies worldwide have been saved, largely because of the efforts to improve the first infant ventilators and the discovery of surfactant a decade later.
Patrick was born at Otis Air Force Base on Cape Cod at about 37 weeks, weighing 4 pounds, 10½ ounces, according to a recent account in The New York Times. As the infant's respiratory distress worsened, he was airlifted to Children's Hospital in Boston, where he was put in a hyperbaric chamber, used mostly for burn victims and divers with the bends or decompression sickness. At the time, Children's was using it for "blue babies," infants born with congenital heart defects that starve their bodies of oxygen and cause a bluish coloration of the skin.
"[Hyperbaric chambers] allowed for a higher oxygen content in their blood, but their lungs were collapsing," said Greenspan.
And oxygen carried risks, such as blindness. Pop singer Stevie Wonder, born six weeks premature, developed retinopathy while in an incubator because of excess oxygen. "We have now learned to control that," he said.