Earlier this year, an ambulance brought a man in his 80s to the emergency room at Brigham and Women’s Hospital in Boston. He had metastatic lung cancer; his family had arranged for hospice care at home.

But when he grew less alert and began struggling to breathe, his son tearfully called 911.

“As soon as I met them, his son said, ‘Put him on a breathing machine,’” recalled Dr. Kei Ouchi, an emergency physician and researcher at the hospital.

Hospice patients know that they are close to death; they and their families have also been instructed that most distressing symptoms, like shortness of breath, can be eased at home.

But the son kept insisting, “Why can’t you put him on a breathing machine?”

Ouchi, lead author of a new study of how older people fare after emergency room intubation, knew this would be no simple decision.

“I went into emergency medicine thinking I’d be saving lives. I used to be very satisfied putting patients on a ventilator,” he told me in an interview.

But he began to realize that while intubation is indeed lifesaving, most older patients came to the ER with serious illnesses. “They sometimes have values and preferences beyond just prolonging their lives,” he said.

Often, he would see the same people he had intubated days later, still in the hospital, very ill, even unresponsive. “Many times, a daughter would say, ‘She would never have wanted this.’”

Like all emergency doctors, he had been trained to perform the procedure — sedating the patient, putting a plastic tube down his throat and then attaching him to a ventilator that would breathe for him.

But, he said, “I was never trained to talk to patients or their families about what this means.”

His study, published in the Journal of the American Geriatrics Society, reveals more about that.

STAGGERING STATISTIC

Analyzing 35,000 intubations of adults over age 65, data gathered from 262 hospitals between 2008 and 2015, Ouchi and his colleagues found that a third of those patients die in the hospital despite intubation (also called “mechanical ventilation”).

Of potentially greater importance to elderly patients — who so often declare they would rather die than spend their lives in nursing homes — are the discharge statistics.

Only a quarter of intubated patients go home from the hospital. Most survivors, 63 percent, go elsewhere, presumably to nursing facilities. The study does not address whether they face short rehab stays or become permanent residents.

But it does document the crucial role that age plays.

After intubation, 31 percent of patients ages 65-74 survive the hospitalization and return home. But for 80- to 84-year-olds, that figure drops to 19 percent; for those over age 90, it slides to 14 percent.

At the same time, the mortality rate climbs sharply, to 50 percent in the eldest cohort from 29 percent in the youngest.

All intubated patients proceed to intensive care, most remaining sedated because intubation is uncomfortable. If they were conscious, patients might try to pull out the tubes or the IV’s delivering nutrition and medications. They cannot speak.

Intubation “is not a walk in the park,” Ouchi said. “This is a significant event for older adults. It can really change your life, if you survive.”

A study at Yale University in 2015 following older adults before and after an ICU stay (average age: 83) confirmed what many geriatricians already understood. Depending on how disabled patients are before a critical illness, they are likely to see a decline in their function afterward, or to die within a year.

HEALTH HAZARD

Those who underwent intubation had more than twice the mortality risk of other ICU patients. “You don’t get better, most of the time,” said Ouchi. While outcomes remain hard to predict, “a lot of times, you get worse.”

Intubation rates are projected to increase. But so has the use of alternatives known as “noninvasive ventilation” — primarily the bipap device, short for bi-level positive airway pressure.

A tightfitting mask over the nose and mouth helps patients with certain conditions breathe nearly as well as intubation does. But they remain conscious and can have the mask removed briefly for a sip of water or a short conversation.

When researchers at the Mayo Clinic undertook an analysis of the technique, reviewing 27 studies of noninvasive ventilation in patients with do-not-intubate or comfort-care-only orders, they found that most survived to discharge. Many, treated on ordinary hospital floors, avoided intensive care.

“There are cases where noninvasive ventilation is comparable or even superior to mechanical ventilation,” said Dr. Douglas White, a critical care physician and ethicist at the University of Pittsburgh School of Medicine.

Ouchi, for instance, explained to his patient’s distraught son that intubation would thwart his father’s desire to remain communicative. The patient, able to see though not to say much, died four days later in a hospital room with bipap and morphine to reduce his “air hunger.”

Most patients in the Mayo review died within a year, too. But bipap may provide an interim option, giving families and physicians time to decide together whether to intubate an ailing older patient, who at this point probably can’t direct his own care.

But discussing how aggressively an older person wants to be treated remains a conversation — probably a series of them — best held before a crisis.

Intubation, for instance, is often something a physician can foresee. Older patients who have cardiorespiratory conditions (emphysema, lung cancer, heart failure), or who are prone to pneumonia, or who have entered the later stages of Alzheimer’s or Parkinson’s disease — any of them may be nearing this crossroads.

When they do, Dr. Michael Wilson, a critical care physician at the Mayo Clinic, opts for a particularly humane approach.

As he recently described in JAMA Internal Medicine, before he inserts the tube, he explains to the patient and family that while he and the staff will do everything they can, people in this circumstance may die.

“You may later wake up and do fine,” he tells his patient. “Or this may be the last time to communicate with your family,” because intubated patients cannot talk.

Since setting up intubation generally takes a few minutes, he encourages people to spend them sharing words of comfort, reassurance and affection. Without that pause, “I have stolen the last words from patients,” he told me.

Wilson has used this approach about 50 times in his ICU, so he has learned what patients and families, given this opportunity, tell one another.

“It’s nearly always, ‘I love you,’” he said.