Updated at 2:04 p.m. on Jan. 21

Tufts Medical Center plans to close its children's hospital this summer, and convert those 41 beds to serve adults.

Michael Tarnoff, president and CEO of Tufts Medical Center, said the children's hospital's fate has been in question for a while, and that the hospital is facing high demand for beds as more adult patients require specialized care. Wellforce, the hospital's parent company, reached an agreement to send pediatric patients who are in need of inpatient care to Boston Children's Hospital in a little over five months, if it receives the necessary state approvals. The announcement devastated staff and concerned families who have questions about what this news means for their children's care.

"This is not happening tomorrow. This is not happening next month, we're planning this over a period of months so that there's a thoughtful transition," Tarnoff told reporters at a press briefing Thursday. "We need to maintain access to care for our community and pediatrics and adults. And this will all help solidify that."

Tarnoff said the news of the closure is hard for the hospital community.

"I would describe it as some agony," he said. "People love this place. People love this institution. People love working here. ... So this comes with a lot of heartache. It comes with a lot of sadness."

But just because it's a difficult decision, he said, doesn't mean it's the wrong decision. The change is necessary, Tarnoff said, because of an increase in adult patients in need of specialized medical care — something he said is not the result of the COVID-19 pandemic. He said the medical center usually has 50% to 75% of pediatric beds in use, while many times all of the adult beds are occupied.

"These demands on Tufts Medical Center were here even pre-pandemic. They've just been intensified," Tarnoff said. "And this question of the scale, the size, the depth and the breadth of our children's hospital — as high quality of care as it provides and as its heart is — has been a longstanding question."

For many who have lived in the region for a while, Tufts Children's Hospital is more commonly thought of as the "Floating Hospital for Children," a throwback to itsfounding in 1894 as a ship commissioned to bring sick children out onto the harbor for fresh air and medical treatment.

"While we can be sensitive and honor the history, we also have to be forward-thinking and really thoughtful about what the community needs the most from us and where care is best situated in different situations," Tarnoff said.

Tufts plans to continue operating its pediatric primary care services and neo-natal intensive care unit.

Tufts Children's Hospital also partners with hundreds of pediatricians' offices around the state, and the announcement has caused concern among some patient families that those resources could be lost.

"We've been in contact with them," Tarnoff said of the hospital's pediatrician partners. "The reliance on us as an inpatient facility is what will change."

Tufts will continue to partner with pediatricians, Tarnoff said, but after the transition, patients will go to Boston Children's Hospital if they need to be admitted to a hospital.

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In a written statement, Boston Children’s Hospital President and CEO Kevin Churchwell emphasized his hospital's commitment to pediatric patients.

“When the leadership of Wellforce approached us with this potential collaboration, we recognized the important positive impact it could have on improving not only pediatric health, but adult health as well," he said in the statment. "We look forward to collaborating with Tufts Medical Center to provide a full range of care to pediatric patients, including inpatient care that cannot be provided in a community hospital setting.”

Tarnoff said Tufts Medical Center will work to ensure that any employees whose jobs are eliminated by the change are able to find positions elsewhere in the Tufts system or at Boston Children's Hospital.

"It's not certain what is going to become of everybody," said Mary Havlicek Cornacchia, a staff nurse in the operating room, and chairperson of the nurses' union bargaining unit at Tufts. "I know that we are working closely with Boston Children's Hospital for transition collaboration. So hopefully all of these staff people will be placed appropriately."

Havlicek Cornacchia has worked at Tufts Medical Center for more than 33 years, and said the news of the closure is devastating to staff.

"We honestly feel like we've been kicked in the stomach," she said. "I can't put it a different way, and I think if they had done that, it would feel better than what it feels like right now. You know, nurses have given their their blood, sweat and tears to this facility, and some of them have been there for as long as I have, or longer. So to suddenly learn that this is not the place that you may continue working after July is just devastating."

Cornacchia said she's concerned that some patients whose insurance plans cover Tufts Children's Hospital as an in-network hospital may not have the same coverage at Boston Children's Hospital.

"That would be one thing for sure that I'd be concerned about, to make sure that that every patient has a place to go," she said.

A spokesperson for Tufts Medical Center said hospital leadership will be working out the insurance issue in the coming months.

For the families of some Tufts patients, the news has created a sense of troubling uncertainty.

Suzanne Gilleece of Methuen has two sons who have severe hemophilia A, a genetic bleeding disorder. They're now 19 and 17 years old, and have been patients at Tufts' pediatric hematology oncology clinic their entire lives.

"The care has been phenomenal," Gilleece said. "It's very much a family-centered clinic, and everyone knows everyone."

Now, it's not clear if the clinic will remain open. A spokesperson for Tufts Medical Center told GBH News that the hospital is in discussions with Boston Children's Hospital on how best to structure the future of Tufts' pediatric subspecialty ambulatory clinics.

That uncertainty has left Gilleece reeling.

"Part of me thinks that they should have not announced it yet until they had worked everything out," she said. "Because it is causing people to be upset and now parents are now like, 'Well, what do we do now? Where do we go from here?' But we don't know anything to do anything. You know, I don't know if any of the doctors are staying. I don't know if they're going other places. I don't know."

This story was updated to include Tarnoff's comments about Tufts Children's Hospital's partnerships with pediatricians' offices.