After years of political wrangling, plans to build a $600 million regional hospital in Prince George’s County are close to being finalized. The financing is nearly in place. A site will soon be chosen.

But one key question remains: How can the new hospital, which would be affiliated with the University of Maryland Medical System, be kept from failing like the one it would replace?

The answer, state and county officials say, is clear: Prince George’s, which is suffering a physician shortage and has many residents who lack health insurance, needs a more robust network of outpatient clinics and private doctors’ offices to better serve its residents.

Such a primary-care network is the only way to ensure that the hospital’s emergency room won’t be overrun by residents seeking basic medical care, officials say. That would cost millions in public funds and could compromise the chief mission of the new hospital: providing specialist and acute care for serious medical conditions to Prince George’s and nearby communities.

The stakes are high. Without a network in place, the University of Maryland Medical System would be reluctant to come in to the county and run the regional medical center, officials have said.

“This is not just about how to fund the project, it is about how to create a health care system,” John W. Ashworth III, senior vice president of the University of Maryland Medical System, told county lawmakers recently.“We believe this is a real opportunity but also a real challenge,” he said.

He said the primary-care network needs to be in place long before the hospital opens in 2017 or the system could unravel. UMMS, he said, is reluctant to join with any business that could “have a negative impact on the viability of the system.”

Attracting more doctors and clinics to Prince George’s will take a major effort.

A RAND study in 2009 found that a disproportionately high number of people who live in predominantly African American Prince George’s suffer from asthma, hypertension, HIV infection, cancer, diabetes and heart disease. Many Prince George’s patients use the emergency room as their primary-care practice because they cannot afford to see a doctor, lack health insurance or live too far from a doctor’s office or walk-in clinic. While those medical services may be free or inexpensive to the patients, the price paid by taxpayers and the hospitals is steep — $30 million annually.

That is the leading cause of the financial problems faced for years by Dimensions Healthcare System, which operates Prince George’s Hospital Center and two other sites in the county.

The UMMS system is expected to operate the new hospital and medical center and tap experts from the University of Maryland Medical School. But officials at UMMS have made clear that it will not be their job to provide basic medical care.

That challenge rests with state and local health officials, who are beginning work on developing a network of primary-care providers and view 2013 as a crucial year in that effort.

“We have to have that safety-net piece in place,” said Sarah Leonhard, chief executive of Greater Baden Medical Services, which offers primary care at several sites to low- and moderate-income residents, including many who lack insurance. “Otherwise the private sector cannot thrive.”

Since the RAND study was issued, little about medical care in Prince George’s has changed. Prince George’s County is short 61 physicians, according to a recent study by the University of Maryland School of Public Health. The county also lacks dentists and other types of outpatient health care providers.

Many residents with health insurance who can afford to pay for preventive care leave the county to see their doctors, according to the public health study . The emergency room is still the provider of choice for many uninsured and underinsured county residents.

Plans for the medical center were unveiled 18 months ago after County Executive Rushern L. Baker III (D) was able to bring together competing factions seeking control of the hospital and its assets. Officials expect by late 2013 to formally apply for state permission to build the new regional medical center, which would also be affiliated with the University of Maryland School of Medicine.

Brad Seamon, a top aide to Baker, said the county will lead the effort to build the primary-care network.

“Our responsibility is to make sure there is a safety net,” said Seamon, the county’s chief administrative officer. “They [UMMS] are in the hospital business.”

Seamon hopes to be able to turn to a toolbox of incentives to lure more medical professionals to Prince George’s who might be attracted by the potential to affiliate with UMMS and the new hospital. As part of that effort, county officials have asked the state to designate a section of Capitol Heights as what they call “a health enterprise zone,” which would make it easier to offer tax breaks and other financial incentives to attract medical-care providers.

There are also plans for nonprofit medical practices already in Prince George’s, such as Dimensions and Greater Baden, to expand.

Dimensions Healthcare System, which runs Prince George’s Hospital Center in Cheverly, and facilities in Bowie and Laurel, expects to open a primary-care office in 2013 next to Prince George’s Hospital Center, and also open a medical suite in Suitland.

CCI, formerly known as Community Clinic Inc., is already serving Prince George’s residents in nearby Takoma Park in Montgomery County. The nonprofit agency is expected to open a primary-care center in Greenbelt by mid-2013.

Mary’s Center in Adelphi is slated to expand in Capitol Heights, as is Greater Baden.

“What we want to do is create a model to [attract] primary-care providers to come to the area,” said Pamela B. Creekmur, a nurse who heads the Prince George’s County Health Department.

She is hoping that the enterprise zone would bring in at least three new providers, along with the two nonprofit groups already serving the area.

“If it is successful, we can do that same thing elsewhere in the county,” she said.

Ashworth acknowledged at the meeting with legislators that there were no similar systems in the state that could be used as models, but several officials have said that the potential for medical practices to affiliate with the UMMS system by joining the primary-care network should be a draw.

The expansion of health insurance through the federal Affordable Care Act should also help spur creation of a primary-care network because patients with insurance usually are more willing to seek regular checkups and other preventive care. That helps lower the incidence of illnesses, both minor and serious, that have led county residents to seek help in emergency rooms.

Creekmur said county officials also are looking at ways to minimize financial disincentives faced by private practitioners, who get reimbursed at a lower rate for Medicaid and Medicare patients than do practitioners in federally approved clinics such as Greater Baden and Mary’s Center.

Creekmur said the county may be able to offset those disparities by assigning county employees to act as care coordinators in private practices in underserved areas. “Without that network, you are going to have unnecessary hospital visits and unnecessary emergency room visits. There are not a lot of places for people to go,” she said.

“We are counting on that to get better. But it doesn’t fall from the sky.”