BALTIMORE — In a church basement in a poor East Baltimore neighborhood, a Johns Hopkins doctor enlisted residents to help answer one of the most fraught questions in public health: When a surge of patients — from a disaster, disease outbreak or terrorist attack — overwhelms hospitals, how should you ration care? Whose lives should be saved first?

For the past several years, Dr. Lee Daugherty Biddison, a critical care physician at Johns Hopkins, and colleagues have led an unusual public debate around Maryland, from Zion Baptist Church in East Baltimore to a wellness center in wealthy Howard County to a hospital on the rural Eastern Shore. Preparing to make recommendations for state officials that could serve as a national model, the researchers heard hundreds of citizens discuss whether a doctor could remove one patient from lifesaving equipment, like a ventilator, to make way for another who might have a better chance of recovering, or take age into consideration in setting priorities.

At that first public forum in 2012 in East Baltimore, Cierra Brown, a former Johns Hopkins Hospital custodian, said she favored a random approach like a lottery. “I don’t think any of us should choose whether a person should live or die,” she said.

Alex Brecht, a youth program developer sitting across from her, said he thought children should be favored over adults. “Just looking at them, seeing their smiles, they have so much potential,” he said.

“Who’s going to raise them?” asked Tiffany Jackson, another participant.

The effort is among the first times, Dr. Daugherty Biddison said, that a state has gathered informed public opinion on these questions before devising policy on them. “I don’t want to be in a position of making these decisions without knowing what you think,” she told the residents. “We as providers,” she said, “don’t want to make those decisions in isolation.”

Rationing already occurs in delivering medical care in the United States, though some practices are little acknowledged. Committees struggle regularly over policies for allocating scarce organs for transplant.

During widespread drug shortages in recent years, doctors have sometimes chosen among cancer patients for proven chemotherapy regimens and among surgical patients for the most effective anesthetics. And doctors sometimes have to choose among patients who need treatment in intensive care units, which are often filled to capacity.

In emergencies, the choices can have immediate life-or-death consequences. After Hurricane Katrina in 2005, doctors made ad hoc decisions about which groups of patients to evacuate from hospitals when floodwaters rose, the power failed and heat climbed. At one medical center, many of the sickest, chosen to go last, died. During the H1N1 influenza pandemic in 2009, thousands of young people developed severe respiratory distress. For some of the most critical cases, doctors tried treatment on heart-lung bypass machines. Rationing took place because the costly and resource-intensive therapy, which doctors were not sure would help, was available in only about 120 hospitals.

Similar scenarios have developed in other countries, wealthy and poor. After the 2011 earthquake and nuclear disaster in Fukushima, Japan, some patients at nearby hospitals, including babies, were selected for flights to safety, while others languished for days as medical supplies dwindled. At one hospital, dozens of older patients were apparently abandoned, according to a report in The Lancet, and many died.

And during the 2014 Ebola epidemic in West Africa, when doctors and nurses could spend only so many minutes inside hot biohazard suits, they struggled with impossible choices over which patients to give care.

Dr. Daugherty Biddison, a vice chairwoman in the department of medicine at Johns Hopkins, said she had first encountered scarce medical resources while doing missionary work overseas. She realized that even Johns Hopkins Hospital, a 1,145-bed facility anchoring the $7.7 billion Johns Hopkins Medicine enterprise, would fail to meet demand in a severe pandemic. When asked to help draw up a plan, she said, she felt uncomfortable with health professionals’ making life-or-death judgments without knowing the values of the broader public.

At least 18 states from New York to California, and numerous hospitals, including the 152 medical centers operated by the Department of Veterans Affairs, have already developed protocols. Some efforts, including Maryland’s, have received funding from a federal program supporting hospital preparedness. But relatively few people know about the plans for allocating scarce resources, and fewer still have been consulted.

Some of these guidelines are nuanced and flexible to context. But others call for doctors to categorically refuse hospital admittance to older adults and those with certain existing medical conditions, such as kidney failure or advanced cancer, in a severe pandemic.

In Maryland, participants in the forums, designed with the help of Carnegie Mellon University’s program for deliberative democracy, tended to favor saving the most lives or years of life by prioritizing people who were expected to survive their current illness or live the longest after being treated. However, many also said that a lottery or first-come-first-served approach would be appropriate for patients who had roughly equal chances of benefiting.

“If you have one ventilator and five people who are good candidates, there’s going to have to be a random sort of chance aspect to it,” said Dr. Eric Toner, a senior associate at the UPMC Center for Health Security and one of the project’s leaders.

Unexpected questions emerged in the discussions: Should an undocumented immigrant be eligible to get a ventilator? What about a drug or alcohol abuser, or a prisoner? After being told by a facilitator that discrimination would not be allowed, one participant asked whether using age, one of the principles under discussion, would not also be a form of discrimination.

Taking ventilators from patients who did not appear to be improving was “the single most contentious issue,” Dr. Toner said. Maryland’s attorney general released an opinion in December that lifesaving medical technology, including ventilators, could be removed from patients during a catastrophic emergency and reassigned to others who could potentially benefit more from them. Dr. Toner said it would be hard for any system to work without reallocation.

But at the forums, many expressed reservations. One woman said that she had been in a coma, on a ventilator, and that her family had been encouraged to turn it off and let her die. “Health care providers are not God,” another said. “I’ve seen it firsthand where they thought one thing and the outcome was different.”

To avoid rationing, a woman proposed a “Susan G. Komen for disaster preparedness,” a reference to the ubiquitous fund-raising movement for a breast cancer cure. Some said they would voluntarily refuse a ventilator to save the lives of other people, such as children or family members. A man questioned whether doctors would even have the time in an emergency to engage in formal rationing. Some with lower incomes said that health care rationing was already occurring based on the ability to pay.

Translating all these ideas into recommendations for the state, most likely in mid-2017, will be challenging. The organizers said that despite the complexity, they were now in a better position to provide the guidelines.

“We have a much fuller appreciation of what the community wants,” said Howard Gwon, the director of the office of emergency management at Johns Hopkins Hospital.

Charles Blattberg, a professor of political philosophy at the University of Montreal, said he worried that the effort could result in overly precise guidelines.

“The kind of judgment that’s required to arrive at a good decision in these situations needs to be extremely sensitive to the context,” he said. “It’s not about just abandoning one lone doctor to their own devices to make it up on the spot, but we can’t go the other extreme in thinking we have the solution to the puzzle already; just follow these instructions. That works for technical problems. These are moral, political problems.”

Ruth Faden, the founder of Johns Hopkins’s Berman Institute of Bioethics, which participated in the project, said she saw value in the exercise far beyond a pandemic.

“It’s a novel and important attempt,” she said, “to turn extremely complicated core ethical considerations into something people can make sense of and struggle with in ordinary language.”